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.dockerignore

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+.git
+.gitignore
+__pycache__
+*.pyc
+*.pyo
+*.pyd
+.DS_Store
+weights/
+results/
+inputs/cropped_faces/
+inputs/gray_faces/
+inputs/masked_faces/
+inputs/whole_imgs/
+output/
+web-demos/

.gitattributes

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.gitignore

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+.vscode
+
+# ignored files
+version.py
+
+# ignored files with suffix
+*.html
+ *.png
+ *.jpeg
+ *.jpg
+*.pt
+*.gif
+*.pth
+*.dat
+*.zip
+
+# template
+
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+MANIFEST
+
+# PyInstaller
+#  Usually these files are written by a python script from a template
+#  before PyInstaller builds the exe, so as to inject date/other infos into it.
+*.manifest
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+
+# Installer logs
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+
+# Unit test / coverage reports
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+
+# Translations
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+
+# Django stuff:
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+# Flask stuff:
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+
+# Sphinx documentation
+docs/_build/
+
+# PyBuilder
+target/
+
+# Jupyter Notebook
+.ipynb_checkpoints
+
+# pyenv
+.python-version
+
+# celery beat schedule file
+celerybeat-schedule
+
+# SageMath parsed files
+*.sage.py
+
+# Environments
+.env
+.venv
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/
+
+# Spyder project settings
+.spyderproject
+.spyproject
+
+# Rope project settings
+.ropeproject
+
+# mkdocs documentation
+/site
+
+# mypy
+.mypy_cache/
+
+# project
+results/
+experiments/
+tb_logger/
+run.sh
+*debug*
+*_old*
+

API_DOCUMENTATION.md

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+# CodeFormer API Documentation
+
+This document describes the programmatic interface for the CodeFormer Face Restoration service.
+
+## Base URL
+The API is accessible at:
+`https://esmailx50-job.hf.space` (or your specific Hugging Face Space URL)
+
+---
+
+## 1. Process Images
+Processes one or more images for face restoration and enhancement.
+
+- **Endpoint:** `/api/process`
+- **Method:** `POST`
+- **Consumes:** `multipart/form-data` OR `application/json`
+
+### Parameters
+| Parameter | Type | Default | Description |
+| :--- | :--- | :--- | :--- |
+| `fidelity` | float | `0.5` | Fidelity weight ($w$). Range [0, 1]. Lower is more "hallucinated" detail, higher is more identity preservation. |
+| `upscale` | int | `2` | Final upscaling factor. Supported: `1`, `2`, `4`. |
+| `background_enhance` | bool | `false` | Enhance the background using Real-ESRGAN. |
+| `face_upsample` | bool | `false` | Upsample restored faces using Real-ESRGAN. |
+| `return_base64` | bool | `false` | If true, includes the processed image as a base64 string in the JSON response. |
+
+### Input Formats
+
+#### A. Multipart Form Data (`multipart/form-data`)
+Useful for uploading files directly.
+- `image`: One or more image files (as a list).
+- Other parameters as form fields.
+
+**Example (curl):**
+```bash
+curl -X POST 
+  -F "image=@my_photo.jpg" 
+  -F "fidelity=0.7" 
+  -F "background_enhance=true" 
+  https://esmailx50-job.hf.space/api/process
+```
+
+#### B. JSON (`application/json`)
+Useful for sending base64-encoded image data.
+- `image_base64`: A single base64 string (with or without data URI prefix).
+- `images_base64`: (Optional) A list of base64 strings for batch processing.
+- Other parameters as JSON keys.
+
+**Example (curl):**
+```bash
+curl -X POST 
+  -H "Content-Type: application/json" 
+  -d '{
+    "image_base64": "data:image/png;base64,iVBORw0KG...",
+    "fidelity": 0.5,
+    "return_base64": true
+  }' 
+  https://esmailx50-job.hf.space/api/process
+```
+
+### Success Response
+```json
+{
+  "status": "success",
+  "count": 1,
+  "results": [
+    {
+      "original_name": "image.png",
+      "filename": "api_result_uuid.png",
+      "image_url": "https://.../static/results/api_result_uuid.png",
+      "image_base64": "iVBORw0KG..." // Only if return_base64 was true
+    }
+  ]
+}
+```
+
+### Error Response
+```json
+{
+  "status": "error",
+  "message": "Detailed error message here"
+}
+```
+
+---
+
+## 2. Health Check
+Checks if the service is online and returns the compute device being used.
+
+- **Endpoint:** `/api/health`
+- **Method:** `GET`
+
+**Success Response:**
+```json
+{
+  "status": "online",
+  "device": "cuda" // or "cpu"
+}
+```
+
+---
+
+## CORS & Integration
+Cross-Origin Resource Sharing (CORS) is enabled for all routes. This allows you to call the API directly from browser-based applications (React, Vue, etc.) without hitting "Same-Origin Policy" blocks.
+
+**Javascript Example (Fetch):**
+```javascript
+const formData = new FormData();
+formData.append('image', fileInput.files[0]);
+formData.append('fidelity', '0.5');
+
+const response = await fetch('https://esmailx50-job.hf.space/api/process', {
+  method: 'POST',
+  body: formData
+});
+const data = await response.json();
+console.log(data.results[0].image_url);
+```

DOCUMENTATION.md

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+# CodeFormer Face Restoration - Project Documentation
+
+## 1. Introduction
+
+**CodeFormer** is a robust blind face restoration algorithm designed to restore old, degraded, or AI-generated face images. It utilizes a **Codebook Lookup Transformer** (VQGAN-based) to predict high-quality facial features even from severe degradation, ensuring that the restored faces look natural and faithful to the original identity.
+
+This project wraps the core CodeFormer research code into a deployable, user-friendly **Flask Web Application**, containerized with **Docker** for easy deployment on platforms like Hugging Face Spaces.
+
+### Key Features
+*   **Blind Face Restoration:** Restores faces from low-quality inputs without knowing the specific degradation details.
+*   **Background Enhancement:** Uses **Real-ESRGAN** to upscale and enhance the non-face background regions of the image.
+*   **Face Alignment & Paste-back:** Automatically detects faces, aligns them for processing, and seamlessly blends them back into the original image.
+*   **Adjustable Fidelity:** Users can balance between restoration quality (hallucinating details) and identity fidelity (keeping the original look).
+
+---
+
+## 2. System Architecture
+
+The application is built on a Python/PyTorch backend served via Flask.
+
+### 2.1 Technology Stack
+*   **Framework:** Flask (Python Web Server)
+*   **Deep Learning:** PyTorch, TorchVision
+*   **Image Processing:** OpenCV, NumPy, Pillow
+*   **Core Libraries:** `basicsr` (Basic Super-Restoration), `facelib` (Face detection/utils)
+*   **Frontend:** HTML5, Bootstrap 5, Jinja2 Templates
+*   **Containerization:** Docker (CUDA-enabled)
+
+### 2.2 Directory Structure
+```
+CodeFormer/
+├── app.py                 # Main Flask application entry point
+├── Dockerfile             # Container configuration
+├── requirements.txt       # Python dependencies
+├── basicsr/               # Core AI framework (Super-Resolution tools)
+├── facelib/               # Face detection and alignment utilities
+├── templates/             # HTML Frontend
+│   ├── index.html         # Upload interface
+│   └── result.html        # Results display
+├── static/                # Static assets (css, js, uploads)
+│   ├── uploads/           # Temporary storage for input images
+│   └── results/           # Temporary storage for processed output
+└── weights/               # Pre-trained model weights (downloaded on startup)
+    ├── CodeFormer/        # CodeFormer model (.pth)
+    ├── facelib/           # Detection (RetinaFace) and Parsing models
+    └── realesrgan/        # Background upscaler (Real-ESRGAN)
+```
+
+### 2.3 Logic Flow
+1.  **Input:** User uploads an image via the Web UI.
+2.  **Pre-processing (`app.py`):**
+    *   Image is saved to `static/uploads`.
+    *   Parameters (fidelity, upscale factor) are parsed.
+3.  **Inference Pipeline:**
+    *   **Detection:** `facelib` detects faces in the image using RetinaFace.
+    *   **Alignment:** Faces are cropped and aligned to a standard 512x512 resolution.
+    *   **Restoration:** The **CodeFormer** model processes the aligned faces.
+    *   **Upscaling (Optional):** The background is upscaled using **Real-ESRGAN**.
+    *   **Paste-back:** Restored faces are warped back to their original positions and blended.
+4.  **Output:** The final image is saved to `static/results` and displayed to the user.
+
+---
+
+## 3. Installation & Deployment
+
+### 3.1 Docker Deployment (Recommended)
+The project is optimized for Docker.
+
+**Prerequisites:** Docker, NVIDIA GPU (optional, but recommended).
+
+1.  **Build the Image:**
+    ```bash
+    docker build -t codeformer-app .
+    ```
+
+2.  **Run the Container:**
+    ```bash
+    # Run on port 7860 (Standard for HF Spaces)
+    docker run -it -p 7860:7860 codeformer-app
+    ```
+    *Note: To use GPU, add the `--gpus all` flag to the run command.*
+
+### 3.2 Hugging Face Spaces Deployment
+This repository is configured for direct deployment to Hugging Face.
+
+1.  Create a **Docker** Space on Hugging Face.
+2.  Push this entire repository to the Space's Git remote.
+    ```bash
+    git remote add hf git@hf.co:spaces/USERNAME/SPACE_NAME
+    git push hf main
+    ```
+3.  The Space will build (approx. 5-10 mins) and launch automatically.
+
+### 3.3 Local Development
+1.  **Install Environment:**
+    ```bash
+    conda create -n codeformer python=3.8
+    conda activate codeformer
+    pip install -r requirements.txt
+    ```
+2.  **Install Basicsr:**
+    ```bash
+    python basicsr/setup.py install
+    ```
+3.  **Run App:**
+    ```bash
+    python app.py
+    ```
+
+---
+
+## 4. User Guide (Web Interface)
+
+### 4.1 Interface Controls
+
+*   **Input Image:** Supports standard formats (JPG, PNG, WEBP). Drag and drop supported.
+*   **Fidelity Weight (w):**
+    *   **Range:** 0.0 to 1.0.
+    *   **0.0 (Better Quality):** The model "hallucinates" more details. Results look very sharp and high-quality but may slightly alter the person's identity (look less like the original).
+    *   **1.0 (Better Identity):** The model sticks strictly to the original features. Results are faithful to the original photo but might be blurrier or contain more artifacts.
+    *   **Recommended:** 0.5 is a balanced default.
+*   **Upscale Factor:**
+    *   Scales the final output resolution (1x, 2x, or 4x).
+    *   *Note: Higher scaling requires more VRAM.*
+*   **Enhance Background:**
+    *   If checked, runs Real-ESRGAN on the non-face areas.
+    *   *Recommendation:* Keep checked for full-photo restoration. Uncheck if you only care about the face or are running on limited hardware.
+*   **Upsample Face:**
+    *   If checked, the restored face is also upsampled to match the background resolution.
+
+### 4.2 Viewing Results
+The result page features an interactive **Before/After Slider**. Drag the handle left and right to compare the pixels of the original versus the restored image directly.
+
+---
+
+## 5. Technical Details
+
+### 5.1 Model Weights
+The application automatically checks for and downloads the following weights to the `weights/` directory on startup:
+
+| Model | Path | Description |
+| :--- | :--- | :--- |
+| **CodeFormer** | `weights/CodeFormer/codeformer.pth` | Main restoration model. |
+| **RetinaFace** | `weights/facelib/detection_Resnet50_Final.pth` | Face detection. |
+| **ParseNet** | `weights/facelib/parsing_parsenet.pth` | Face parsing (segmentation). |
+| **Real-ESRGAN** | `weights/realesrgan/RealESRGAN_x2plus.pth` | Background upscaler (x2). |
+
+### 5.2 Performance Notes
+*   **Memory:** The full pipeline (CodeFormer + Real-ESRGAN) requires significant RAM/VRAM. On CPU-only environments (like basic HF Spaces), processing a single image may take 30-60 seconds.
+*   **Git LFS:** Image assets in this repository are tracked with Git LFS to keep the repo size manageable.
+
+---
+
+## 6. Credits & References
+
+*   **Original Paper:** [Towards Robust Blind Face Restoration with Codebook Lookup Transformer (NeurIPS 2022)](https://arxiv.org/abs/2206.11253)
+*   **Authors:** Shangchen Zhou, Kelvin C.K. Chan, Chongyi Li, Chen Change Loy (S-Lab, Nanyang Technological University).
+*   **Original Repository:** [sczhou/CodeFormer](https://github.com/sczhou/CodeFormer)

Dockerfile

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+FROM pytorch/pytorch:1.13.1-cuda11.6-cudnn8-devel
+
+WORKDIR /code
+
+# Install system dependencies
+RUN apt-get update && apt-get install -y \
+    libgl1 \
+    libglib2.0-0 \
+    git \
+    ninja-build \
+    && rm -rf /var/lib/apt/lists/*
+
+# Copy requirements
+COPY requirements.txt .
+
+# Install python dependencies
+RUN pip install --no-cache-dir -r requirements.txt
+
+# Copy application code
+COPY . .
+
+# Create necessary directories and set permissions
+RUN mkdir -p weights inputs output static && \
+    chmod 777 weights inputs output static
+
+# Install basicsr (build extensions in-place)
+RUN python basicsr/setup.py build_ext --inplace
+
+# Create a non-root user and switch to it
+RUN useradd -m -u 1000 user
+USER user
+ENV HOME=/home/user \
+    PATH=/home/user/.local/bin:$PATH
+
+WORKDIR /code
+
+EXPOSE 7860
+
+CMD ["python", "app.py"]

LICENSE

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+S-Lab License 1.0
+
+Copyright 2022 S-Lab
+
+Redistribution and use for non-commercial purpose in source and 
+binary forms, with or without modification, are permitted provided 
+that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright 
+   notice, this list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright 
+   notice, this list of conditions and the following disclaimer in 
+   the documentation and/or other materials provided with the 
+   distribution.
+
+3. Neither the name of the copyright holder nor the names of its 
+   contributors may be used to endorse or promote products derived 
+   from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 
+HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+In the event that redistribution and/or use for commercial purpose in 
+source or binary forms, with or without modification is required, 
+please contact the contributor(s) of the work.

README.md

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----
-title: Codeformer
-emoji: 🦀
-colorFrom: purple
-colorTo: yellow
-sdk: docker
-pinned: false
----
-
-Check out the configuration reference at https://huggingface.co/docs/hub/spaces-config-reference
+---
+title: CodeFormer
+emoji: 👤
+colorFrom: blue
+colorTo: purple
+sdk: docker
+app_file: app.py
+pinned: false
+---
+
+<p align="center">
+  <img src="assets/CodeFormer_logo.png" height=110>
+</p>
+
+## Towards Robust Blind Face Restoration with Codebook Lookup Transformer (NeurIPS 2022)
+
+[Paper](https://arxiv.org/abs/2206.11253) | [Project Page](https://shangchenzhou.com/projects/CodeFormer/) | [Video](https://youtu.be/d3VDpkXlueI)
+
+
+<a href="https://colab.research.google.com/drive/1m52PNveE4PBhYrecj34cnpEeiHcC5LTb?usp=sharing"><img src="https://colab.research.google.com/assets/colab-badge.svg" alt="google colab logo"></a> [![Hugging Face](https://img.shields.io/badge/Demo-%F0%9F%A4%97%20Hugging%20Face-blue)](https://huggingface.co/spaces/sczhou/CodeFormer) [![Replicate](https://img.shields.io/badge/Demo-%F0%9F%9A%80%20Replicate-blue)](https://replicate.com/sczhou/codeformer) [![OpenXLab](https://img.shields.io/badge/Demo-%F0%9F%90%BC%20OpenXLab-blue)](https://openxlab.org.cn/apps/detail/ShangchenZhou/CodeFormer) ![Visitors](https://api.infinitescript.com/badgen/count?name=sczhou/CodeFormer&ltext=Visitors)
+
+
+[Shangchen Zhou](https://shangchenzhou.com/), [Kelvin C.K. Chan](https://ckkelvinchan.github.io/), [Chongyi Li](https://li-chongyi.github.io/), [Chen Change Loy](https://www.mmlab-ntu.com/person/ccloy/) 
+
+S-Lab, Nanyang Technological University
+
+<img src="assets/network.jpg" width="800px"/>
+
+
+:star: If CodeFormer is helpful to your images or projects, please help star this repo. Thanks! :hugs: 
+
+
+### Update
+- **2023.07.20**: Integrated to :panda_face: [OpenXLab](https://openxlab.org.cn/apps). Try out online demo! [![OpenXLab](https://img.shields.io/badge/Demo-%F0%9F%90%BC%20OpenXLab-blue)](https://openxlab.org.cn/apps/detail/ShangchenZhou/CodeFormer)
+- **2023.04.19**: :whale: Training codes and config files are public available now.
+- **2023.04.09**: Add features of inpainting and colorization for cropped and aligned face images.
+- **2023.02.10**: Include `dlib` as a new face detector option, it produces more accurate face identity.
+- **2022.10.05**: Support video input `--input_path [YOUR_VIDEO.mp4]`. Try it to enhance your videos! :clapper: 
+- **2022.09.14**: Integrated to :hugs: [Hugging Face](https://huggingface.co/spaces). Try out online demo! [![Hugging Face](https://img.shields.io/badge/Demo-%F0%9F%A4%97%20Hugging%20Face-blue)](https://huggingface.co/spaces/sczhou/CodeFormer)
+- **2022.09.09**: Integrated to :rocket: [Replicate](https://replicate.com/explore). Try out online demo! [![Replicate](https://img.shields.io/badge/Demo-%F0%9F%9A%80%20Replicate-blue)](https://replicate.com/sczhou/codeformer)
+- [**More**](docs/history_changelog.md)
+
+### TODO
+- [x] Add training code and config files
+- [x] Add checkpoint and script for face inpainting
+- [x] Add checkpoint and script for face colorization
+- [x] ~~Add background image enhancement~~
+
+#### :panda_face: Try Enhancing Old Photos / Fixing AI-arts
+[<img src="assets/imgsli_1.jpg" height="226px"/>](https://imgsli.com/MTI3NTE2) [<img src="assets/imgsli_2.jpg" height="226px"/>](https://imgsli.com/MTI3NTE1) [<img src="assets/imgsli_3.jpg" height="226px"/>](https://imgsli.com/MTI3NTIw) 
+
+#### Face Restoration
+
+<img src="assets/restoration_result1.png" width="400px"/> <img src="assets/restoration_result2.png" width="400px"/>
+<img src="assets/restoration_result3.png" width="400px"/> <img src="assets/restoration_result4.png" width="400px"/>
+
+#### Face Color Enhancement and Restoration
+
+<img src="assets/color_enhancement_result1.png" width="400px"/> <img src="assets/color_enhancement_result2.png" width="400px"/>
+
+#### Face Inpainting
+
+<img src="assets/inpainting_result1.png" width="400px"/> <img src="assets/inpainting_result2.png" width="400px"/>
+
+
+
+### Dependencies and Installation
+
+- Pytorch >= 1.7.1
+- CUDA >= 10.1
+- Other required packages in `requirements.txt`
+```
+# git clone this repository
+git clone https://github.com/sczhou/CodeFormer
+cd CodeFormer
+
+# create new anaconda env
+conda create -n codeformer python=3.8 -y
+conda activate codeformer
+
+# install python dependencies
+pip3 install -r requirements.txt
+python basicsr/setup.py develop
+conda install -c conda-forge dlib (only for face detection or cropping with dlib)
+```
+<!-- conda install -c conda-forge dlib -->
+
+### Quick Inference
+
+#### Download Pre-trained Models:
+Download the facelib and dlib pretrained models from [[Releases](https://github.com/sczhou/CodeFormer/releases/tag/v0.1.0) | [Google Drive](https://drive.google.com/drive/folders/1b_3qwrzY_kTQh0-SnBoGBgOrJ_PLZSKm?usp=sharing) | [OneDrive](https://entuedu-my.sharepoint.com/:f:/g/personal/s200094_e_ntu_edu_sg/EvDxR7FcAbZMp_MA9ouq7aQB8XTppMb3-T0uGZ_2anI2mg?e=DXsJFo)] to the `weights/facelib` folder. You can manually download the pretrained models OR download by running the following command:
+```
+python scripts/download_pretrained_models.py facelib
+python scripts/download_pretrained_models.py dlib (only for dlib face detector)
+```
+
+Download the CodeFormer pretrained models from [[Releases](https://github.com/sczhou/CodeFormer/releases/tag/v0.1.0) | [Google Drive](https://drive.google.com/drive/folders/1CNNByjHDFt0b95q54yMVp6Ifo5iuU6QS?usp=sharing) | [OneDrive](https://entuedu-my.sharepoint.com/:f:/g/personal/s200094_e_ntu_edu_sg/EoKFj4wo8cdIn2-TY2IV6CYBhZ0pIG4kUOeHdPR_A5nlbg?e=AO8UN9)] to the `weights/CodeFormer` folder. You can manually download the pretrained models OR download by running the following command:
+```
+python scripts/download_pretrained_models.py CodeFormer
+```
+
+#### Prepare Testing Data:
+You can put the testing images in the `inputs/TestWhole` folder. If you would like to test on cropped and aligned faces, you can put them in the `inputs/cropped_faces` folder. You can get the cropped and aligned faces by running the following command:
+```
+# you may need to install dlib via: conda install -c conda-forge dlib
+python scripts/crop_align_face.py -i [input folder] -o [output folder]
+```
+
+
+#### Testing:
+[Note] If you want to compare CodeFormer in your paper, please run the following command indicating `--has_aligned` (for cropped and aligned face), as the command for the whole image will involve a process of face-background fusion that may damage hair texture on the boundary, which leads to unfair comparison.
+
+Fidelity weight *w* lays in [0, 1]. Generally, smaller *w* tends to produce a higher-quality result, while larger *w* yields a higher-fidelity result. The results will be saved in the `results` folder.
+
+
+🧑🏻 Face Restoration (cropped and aligned face)
+```
+# For cropped and aligned faces (512x512)
+python inference_codeformer.py -w 0.5 --has_aligned --input_path [image folder]|[image path]
+```
+
+:framed_picture: Whole Image Enhancement
+```
+# For whole image
+# Add '--bg_upsampler realesrgan' to enhance the background regions with Real-ESRGAN
+# Add '--face_upsample' to further upsample restorated face with Real-ESRGAN
+python inference_codeformer.py -w 0.7 --input_path [image folder]|[image path]
+```
+
+:clapper: Video Enhancement
+```
+# For Windows/Mac users, please install ffmpeg first
+conda install -c conda-forge ffmpeg
+```
+```
+# For video clips
+# Video path should end with '.mp4'|'.mov'|'.avi'
+python inference_codeformer.py --bg_upsampler realesrgan --face_upsample -w 1.0 --input_path [video path]
+```
+
+🌈 Face Colorization (cropped and aligned face)
+```
+# For cropped and aligned faces (512x512)
+# Colorize black and white or faded photo
+python inference_colorization.py --input_path [image folder]|[image path]
+```
+
+🎨 Face Inpainting (cropped and aligned face)
+```
+# For cropped and aligned faces (512x512)
+# Inputs could be masked by white brush using an image editing app (e.g., Photoshop) 
+# (check out the examples in inputs/masked_faces)
+python inference_inpainting.py --input_path [image folder]|[image path]
+```
+### Training:
+The training commands can be found in the documents: [English](docs/train.md) **|** [简体中文](docs/train_CN.md).
+
+### License
+
+This project is licensed under <a rel="license" href="https://github.com/sczhou/CodeFormer/blob/master/LICENSE">NTU S-Lab License 1.0</a>. Redistribution and use should follow this license.
+
+---
+### 🐼 Ecosystem Applications & Deployments
+
+CodeFormer has been widely adopted and deployed across a broad range (>20) of online applications, platforms, API services, and independent websites, and has also been integrated into many open-source projects and toolkits.
+
+> Only demos on **Hugging Face Space**, **Replicate**, and **OpenXLab** are official deployments **maintained by the authors**. All other demos, APIs, apps, websites, and integrations listed below are **third-party (non-official)** and are not affiliated with the CodeFormer authors. Please verify their legitimacy to avoid potential financial loss.
+
+
+#### Websites (Non-official)
+
+⚠️⚠️⚠️ The following websites are **not official and are not operated by us**. They use our models without any license or authorization. Please verify their legitimacy to avoid potential financial loss.
+
+
+| Website | Link | Notes |
+|---------|------|--------|
+| CodeFormer.net | https://codeformer.net/ | Non-official website |
+| CodeFormer.cn | https://www.codeformer.cn/ | Non-official website |
+| CodeFormerAI.com | https://codeformerai.com/ | Non-official website |
+
+#### Online Demos / API Platforms
+
+| Platform | Link | Notes |
+|----------|------|--------|
+| Hugging Face | https://huggingface.co/spaces/sczhou/CodeFormer | Maintained by Authors |
+| Replicate | https://replicate.com/sczhou/codeformer | Maintained by Authors |
+| OpenXLab | https://openxlab.org.cn/apps/detail/ShangchenZhou/CodeFormer |Maintained by Authors |
+| Segmind | https://www.segmind.com/models/codeformer | Non-official |
+| Sieve | https://www.sievedata.com/functions/sieve/codeformer | Non-official |
+| Fal.ai | https://fal.ai/models/fal-ai/codeformer | Non-official |
+| VaikerAI | https://vaikerai.com/sczhou/codeformer | Non-official |
+| Scade.pro | https://www.scade.pro/processors/lucataco-codeformer | Non-official |
+| Grandline | https://www.grandline.ai/model/codeformer | Non-official |
+| AI Demos | https://aidemos.com/tools/codeformer | Non-official |
+| Synexa | https://synexa.ai/explore/sczhou/codeformer | Non-official |
+| RentPrompts | https://rentprompts.ai/models/Codeformer | Non-official |
+| ElevaticsAI | https://elevatics.ai/models/super-resolution/codeformer | Non-official |
+| Anakin.ai | https://anakin.ai/apps/codeformer-online-face-restoration-by-codeformer-19343 | Non-official |
+| Relayto | https://relayto.com/explore/codeformer-yf9rj8kwc7zsr | Non-official |
+
+
+#### Open-Source Projects & Toolkits
+
+| Project / Toolkit | Link | Notes |
+|-------------------|------|--------|
+| Stable Diffusion GUI | https://nmkd.itch.io/t2i-gui | Integration |
+| Stable Diffusion WebUI | https://github.com/AUTOMATIC1111/stable-diffusion-webui | Integration |
+| ChaiNNer | https://github.com/chaiNNer-org/chaiNNer | Integration |
+| PyPI | https://pypi.org/project/codeformer/ ; https://pypi.org/project/codeformer-pip/ | Python packages |
+| ComfyUI | https://stable-diffusion-art.com/codeformer/ | Integration |
+
+---
+### Acknowledgement
+
+This project is based on [BasicSR](https://github.com/XPixelGroup/BasicSR). Some codes are brought from [Unleashing Transformers](https://github.com/samb-t/unleashing-transformers), [YOLOv5-face](https://github.com/deepcam-cn/yolov5-face), and [FaceXLib](https://github.com/xinntao/facexlib). We also adopt [Real-ESRGAN](https://github.com/xinntao/Real-ESRGAN) to support background image enhancement. Thanks for their awesome works.
+
+### Citation
+If our work is useful for your research, please consider citing:
+
+    @inproceedings{zhou2022codeformer,
+        author = {Zhou, Shangchen and Chan, Kelvin C.K. and Li, Chongyi and Loy, Chen Change},
+        title = {Towards Robust Blind Face Restoration with Codebook Lookup TransFormer},
+        booktitle = {NeurIPS},
+        year = {2022}
+    }
+
+
+### Contact
+If you have any questions, please feel free to reach me out at `shangchenzhou@gmail.com`. 

app.py

@@ -0,0 +1,358 @@
+"""
+CodeFormer Flask Application
+Deployment on Hugging Face Spaces
+"""
+
+import os
+import cv2
+import torch
+import uuid
+import numpy as np
+import zipfile
+import base64
+from flask import Flask, render_template, request, send_file, url_for, jsonify, send_from_directory
+from flask_cors import CORS
+from werkzeug.utils import secure_filename
+
+from torchvision.transforms.functional import normalize
+from basicsr.archs.rrdbnet_arch import RRDBNet
+from basicsr.utils import imwrite, img2tensor, tensor2img
+from basicsr.utils.download_util import load_file_from_url
+from basicsr.utils.misc import gpu_is_available, get_device
+from basicsr.utils.realesrgan_utils import RealESRGANer
+from basicsr.utils.registry import ARCH_REGISTRY
+
+from facelib.utils.face_restoration_helper import FaceRestoreHelper
+from facelib.utils.misc import is_gray
+
+# --- Initialization ---
+app = Flask(__name__)
+CORS(app) # Enable CORS for all routes
+app.config['UPLOAD_FOLDER'] = 'static/uploads'
+app.config['RESULT_FOLDER'] = 'static/results'
+app.config['MAX_CONTENT_LENGTH'] = 100 * 1024 * 1024  # 100MB limit
+
+# Ensure directories exist
+os.makedirs(app.config['UPLOAD_FOLDER'], exist_ok=True)
+os.makedirs(app.config['RESULT_FOLDER'], exist_ok=True)
+os.makedirs('weights/CodeFormer', exist_ok=True)
+os.makedirs('weights/facelib', exist_ok=True)
+os.makedirs('weights/realesrgan', exist_ok=True)
+
+# Pretrained model URLs
+pretrain_model_url = {
+    'codeformer': 'https://github.com/sczhou/CodeFormer/releases/download/v0.1.0/codeformer.pth',
+    'detection': 'https://github.com/sczhou/CodeFormer/releases/download/v0.1.0/detection_Resnet50_Final.pth',
+    'parsing': 'https://github.com/sczhou/CodeFormer/releases/download/v0.1.0/parsing_parsenet.pth',
+    'realesrgan': 'https://github.com/sczhou/CodeFormer/releases/download/v0.1.0/RealESRGAN_x2plus.pth'
+}
+
+def download_weights():
+    if not os.path.exists('weights/CodeFormer/codeformer.pth'):
+        load_file_from_url(url=pretrain_model_url['codeformer'], model_dir='weights/CodeFormer', progress=True, file_name=None)
+    if not os.path.exists('weights/facelib/detection_Resnet50_Final.pth'):
+        load_file_from_url(url=pretrain_model_url['detection'], model_dir='weights/facelib', progress=True, file_name=None)
+    if not os.path.exists('weights/facelib/parsing_parsenet.pth'):
+        load_file_from_url(url=pretrain_model_url['parsing'], model_dir='weights/facelib', progress=True, file_name=None)
+    if not os.path.exists('weights/realesrgan/RealESRGAN_x2plus.pth'):
+        load_file_from_url(url=pretrain_model_url['realesrgan'], model_dir='weights/realesrgan', progress=True, file_name=None)
+
+# Download weights on startup
+print("Checking weights...")
+download_weights()
+
+# Global models
+device = get_device()
+upsampler = None
+codeformer_net = None
+
+def init_models():
+    global upsampler, codeformer_net
+    
+    # RealESRGAN
+    half = True if gpu_is_available() else False
+    model = RRDBNet(num_in_ch=3, num_out_ch=3, num_feat=64, num_block=23, num_grow_ch=32, scale=2)
+    upsampler = RealESRGANer(
+        scale=2,
+        model_path="weights/realesrgan/RealESRGAN_x2plus.pth",
+        model=model,
+        tile=400,
+        tile_pad=40,
+        pre_pad=0,
+        half=half,
+    )
+
+    # CodeFormer
+    codeformer_net = ARCH_REGISTRY.get("CodeFormer")(
+        dim_embd=512,
+        codebook_size=1024,
+        n_head=8,
+        n_layers=9,
+        connect_list=["32", "64", "128", "256"],
+    ).to(device)
+    
+    ckpt_path = "weights/CodeFormer/codeformer.pth"
+    checkpoint = torch.load(ckpt_path)["params_ema"]
+    codeformer_net.load_state_dict(checkpoint)
+    codeformer_net.eval()
+    print("Models loaded successfully.")
+
+init_models()
+
+def process_image(img_path, background_enhance, face_upsample, upscale, codeformer_fidelity):
+    """Core inference logic"""
+    try:
+        # Defaults
+        has_aligned = False
+        only_center_face = False
+        draw_box = False
+        detection_model = "retinaface_resnet50"
+
+        img = cv2.imread(img_path, cv2.IMREAD_COLOR)
+        
+        # Memory safety checks
+        upscale = int(upscale)
+        if upscale > 4: upscale = 4
+        if upscale > 2 and max(img.shape[:2]) > 1000: upscale = 2
+        if max(img.shape[:2]) > 1500:
+            upscale = 1
+            background_enhance = False
+            face_upsample = False
+
+        face_helper = FaceRestoreHelper(
+            upscale,
+            face_size=512,
+            crop_ratio=(1, 1),
+            det_model=detection_model,
+            save_ext="png",
+            use_parse=True,
+            device=device,
+        )
+        
+        bg_upsampler = upsampler if background_enhance else None
+        face_upsampler = upsampler if face_upsample else None
+
+        if has_aligned:
+            img = cv2.resize(img, (512, 512), interpolation=cv2.INTER_LINEAR)
+            face_helper.is_gray = is_gray(img, threshold=5)
+            face_helper.cropped_faces = [img]
+        else:
+            face_helper.read_image(img)
+            face_helper.get_face_landmarks_5(only_center_face=only_center_face, resize=640, eye_dist_threshold=5)
+            face_helper.align_warp_face()
+
+        # Face restoration
+        for idx, cropped_face in enumerate(face_helper.cropped_faces):
+            cropped_face_t = img2tensor(cropped_face / 255.0, bgr2rgb=True, float32=True)
+            normalize(cropped_face_t, (0.5, 0.5, 0.5), (0.5, 0.5, 0.5), inplace=True)
+            cropped_face_t = cropped_face_t.unsqueeze(0).to(device)
+
+            try:
+                with torch.no_grad():
+                    output = codeformer_net(cropped_face_t, w=codeformer_fidelity, adain=True)[0]
+                    restored_face = tensor2img(output, rgb2bgr=True, min_max=(-1, 1))
+            except Exception as e:
+                print(f"Inference error: {e}")
+                restored_face = tensor2img(cropped_face_t, rgb2bgr=True, min_max=(-1, 1))
+
+            restored_face = restored_face.astype("uint8")
+            face_helper.add_restored_face(restored_face)
+
+        # Paste back
+        if not has_aligned:
+            bg_img = bg_upsampler.enhance(img, outscale=upscale)[0] if bg_upsampler else None
+            face_helper.get_inverse_affine(None)
+            
+            if face_upsample and face_upsampler:
+                restored_img = face_helper.paste_faces_to_input_image(upsample_img=bg_img, draw_box=draw_box, face_upsampler=face_upsampler)
+            else:
+                restored_img = face_helper.paste_faces_to_input_image(upsample_img=bg_img, draw_box=draw_box)
+        else:
+            restored_img = face_helper.restored_faces[0]
+
+        return restored_img
+
+    except Exception as e:
+        print(f"Global processing error: {e}")
+        return None
+
+# --- Routes ---
+
+@app.route('/', methods=['GET'])
+def index():
+    return render_template('index.html')
+
+@app.route('/process', methods=['POST'])
+def process():
+    if 'image' not in request.files:
+        return "No image uploaded", 400
+    
+    files = request.files.getlist('image')
+    if not files or files[0].filename == '':
+        return "No selected file", 400
+
+    results = []
+
+    # Get params (same for all images)
+    try:
+        fidelity = float(request.form.get('fidelity', 0.5))
+        upscale = 4 # Enforce 4x upscale
+        background_enhance = 'background_enhance' in request.form
+        face_upsample = 'face_upsample' in request.form
+    except ValueError:
+        return "Invalid parameters", 400
+
+    for file in files:
+        if file.filename == '': continue
+
+        # Save input
+        filename = str(uuid.uuid4()) + "_" + secure_filename(file.filename)
+        input_path = os.path.join(app.config['UPLOAD_FOLDER'], filename)
+        file.save(input_path)
+
+        # Process
+        result_img = process_image(input_path, background_enhance, face_upsample, upscale, fidelity)
+        
+        if result_img is None:
+            continue # Skip failed images or handle error appropriately
+
+        # Save output
+        output_filename = "result_" + filename.rsplit('.', 1)[0] + ".png"
+        output_path = os.path.join(app.config['RESULT_FOLDER'], output_filename)
+        imwrite(result_img, output_path)
+
+        # Generate preview (max 1000px width/height)
+        preview_filename = "preview_" + output_filename
+        preview_path = os.path.join(app.config['RESULT_FOLDER'], preview_filename)
+        
+        h, w = result_img.shape[:2]
+        if max(h, w) > 1000:
+            scale = 1000 / max(h, w)
+            preview_img = cv2.resize(result_img, None, fx=scale, fy=scale, interpolation=cv2.INTER_AREA)
+            imwrite(preview_img, preview_path)
+        else:
+            preview_filename = output_filename
+
+        results.append({
+            'original': filename,
+            'preview': preview_filename,
+            'download': output_filename
+        })
+
+    if not results:
+        return "Processing failed for all images", 500
+
+    # Create ZIP of all results
+    zip_filename = f"batch_{uuid.uuid4()}.zip"
+    zip_path = os.path.join(app.config['RESULT_FOLDER'], zip_filename)
+    
+    with zipfile.ZipFile(zip_path, 'w') as zipf:
+        for item in results:
+            file_path = os.path.join(app.config['RESULT_FOLDER'], item['download'])
+            zipf.write(file_path, item['download'])
+
+    return render_template('result.html', results=results, zip_filename=zip_filename)
+
+# --- API Routes ---
+
+@app.route('/api/process', methods=['POST'])
+def api_process():
+    """
+    API endpoint for image processing.
+    Accepts:
+    - multipart/form-data with one or more 'image' files.
+    - application/json with 'image_base64' string (single image) or 'images_base64' list.
+    Parameters (form or JSON):
+    - fidelity: (float) 0-1, default 0.5.
+    - background_enhance: (bool) default False.
+    - face_upsample: (bool) default False.
+    - upscale: (int) 1-4, default 2.
+    - return_base64: (bool) default False.
+    """
+    try:
+        is_json = request.is_json
+        data = request.get_json() if is_json else request.form
+        
+        fidelity = float(data.get('fidelity', 0.5))
+        background_enhance = (str(data.get('background_enhance', 'false')).lower() == 'true') if not is_json else data.get('background_enhance', False)
+        face_upsample = (str(data.get('face_upsample', 'false')).lower() == 'true') if not is_json else data.get('face_upsample', False)
+        upscale = int(data.get('upscale', 2))
+        return_base64 = (str(data.get('return_base64', 'false')).lower() == 'true') if not is_json else data.get('return_base64', False)
+
+        processed_images = []
+        inputs = []
+
+        # Handle JSON input
+        if is_json:
+            if 'image_base64' in data:
+                inputs.append({'data': data['image_base64'], 'name': 'image.png'})
+            elif 'images_base64' in data:
+                for idx, img_b64 in enumerate(data['images_base64']):
+                    inputs.append({'data': img_b64, 'name': f'image_{idx}.png'})
+            
+            for inp in inputs:
+                temp_filename = str(uuid.uuid4())
+                image_data = base64.b64decode(inp['data'].split(',')[-1])
+                input_path = os.path.join(app.config['UPLOAD_FOLDER'], f"{temp_filename}.png")
+                with open(input_path, 'wb') as f:
+                    f.write(image_data)
+                inp['path'] = input_path
+                inp['temp_id'] = temp_filename
+
+        # Handle Multipart input
+        elif 'image' in request.files:
+            files = request.files.getlist('image')
+            for file in files:
+                if file.filename != '':
+                    temp_filename = str(uuid.uuid4())
+                    filename = f"{temp_filename}_{secure_filename(file.filename)}"
+                    input_path = os.path.join(app.config['UPLOAD_FOLDER'], filename)
+                    file.save(input_path)
+                    inputs.append({'path': input_path, 'name': file.filename, 'temp_id': temp_filename})
+
+        if not inputs:
+            return jsonify({"status": "error", "message": "No images provided"}), 400
+
+        for inp in inputs:
+            # Process image
+            result_img = process_image(inp['path'], background_enhance, face_upsample, upscale, fidelity)
+            if result_img is not None:
+                # Save result
+                output_filename = f"api_result_{inp['temp_id']}.png"
+                output_path = os.path.join(app.config['RESULT_FOLDER'], output_filename)
+                imwrite(result_img, output_path)
+
+                res = {
+                    "original_name": inp['name'],
+                    "image_url": url_for('static', filename=f'results/{output_filename}', _external=True),
+                    "filename": output_filename
+                }
+
+                if return_base64:
+                    _, buffer = cv2.imencode('.png', result_img)
+                    img_base64 = base64.b64encode(buffer).decode('utf-8')
+                    res["image_base64"] = img_base64
+                
+                processed_images.append(res)
+
+        if not processed_images:
+            return jsonify({"status": "error", "message": "Processing failed for all images"}), 500
+
+        return jsonify({
+            "status": "success",
+            "count": len(processed_images),
+            "results": processed_images
+        })
+
+    except Exception as e:
+        import traceback
+        traceback.print_exc()
+        return jsonify({"status": "error", "message": str(e)}), 500
+
+@app.route('/api/health', methods=['GET'])
+def health_check():
+    return jsonify({"status": "online", "device": str(device)})
+
+if __name__ == '__main__':
+    # Docker/HF Spaces entry point
+    app.run(host='0.0.0.0', port=7860)

basicsr/VERSION

@@ -0,0 +1 @@
+1.3.2

basicsr/__init__.py

@@ -0,0 +1,11 @@
+# https://github.com/xinntao/BasicSR
+# flake8: noqa
+from .archs import *
+from .data import *
+from .losses import *
+from .metrics import *
+from .models import *
+from .ops import *
+from .train import *
+from .utils import *
+from .version import __gitsha__, __version__

basicsr/archs/__init__.py

@@ -0,0 +1,25 @@
+import importlib
+from copy import deepcopy
+from os import path as osp
+
+from basicsr.utils import get_root_logger, scandir
+from basicsr.utils.registry import ARCH_REGISTRY
+
+__all__ = ['build_network']
+
+# automatically scan and import arch modules for registry
+# scan all the files under the 'archs' folder and collect files ending with
+# '_arch.py'
+arch_folder = osp.dirname(osp.abspath(__file__))
+arch_filenames = [osp.splitext(osp.basename(v))[0] for v in scandir(arch_folder) if v.endswith('_arch.py')]
+# import all the arch modules
+_arch_modules = [importlib.import_module(f'basicsr.archs.{file_name}') for file_name in arch_filenames]
+
+
+def build_network(opt):
+    opt = deepcopy(opt)
+    network_type = opt.pop('type')
+    net = ARCH_REGISTRY.get(network_type)(**opt)
+    logger = get_root_logger()
+    logger.info(f'Network [{net.__class__.__name__}] is created.')
+    return net

basicsr/archs/arcface_arch.py

@@ -0,0 +1,245 @@
+import torch.nn as nn
+from basicsr.utils.registry import ARCH_REGISTRY
+
+
+def conv3x3(inplanes, outplanes, stride=1):
+    """A simple wrapper for 3x3 convolution with padding.
+
+    Args:
+        inplanes (int): Channel number of inputs.
+        outplanes (int): Channel number of outputs.
+        stride (int): Stride in convolution. Default: 1.
+    """
+    return nn.Conv2d(inplanes, outplanes, kernel_size=3, stride=stride, padding=1, bias=False)
+
+
+class BasicBlock(nn.Module):
+    """Basic residual block used in the ResNetArcFace architecture.
+
+    Args:
+        inplanes (int): Channel number of inputs.
+        planes (int): Channel number of outputs.
+        stride (int): Stride in convolution. Default: 1.
+        downsample (nn.Module): The downsample module. Default: None.
+    """
+    expansion = 1  # output channel expansion ratio
+
+    def __init__(self, inplanes, planes, stride=1, downsample=None):
+        super(BasicBlock, self).__init__()
+        self.conv1 = conv3x3(inplanes, planes, stride)
+        self.bn1 = nn.BatchNorm2d(planes)
+        self.relu = nn.ReLU(inplace=True)
+        self.conv2 = conv3x3(planes, planes)
+        self.bn2 = nn.BatchNorm2d(planes)
+        self.downsample = downsample
+        self.stride = stride
+
+    def forward(self, x):
+        residual = x
+
+        out = self.conv1(x)
+        out = self.bn1(out)
+        out = self.relu(out)
+
+        out = self.conv2(out)
+        out = self.bn2(out)
+
+        if self.downsample is not None:
+            residual = self.downsample(x)
+
+        out += residual
+        out = self.relu(out)
+
+        return out
+
+
+class IRBlock(nn.Module):
+    """Improved residual block (IR Block) used in the ResNetArcFace architecture.
+
+    Args:
+        inplanes (int): Channel number of inputs.
+        planes (int): Channel number of outputs.
+        stride (int): Stride in convolution. Default: 1.
+        downsample (nn.Module): The downsample module. Default: None.
+        use_se (bool): Whether use the SEBlock (squeeze and excitation block). Default: True.
+    """
+    expansion = 1  # output channel expansion ratio
+
+    def __init__(self, inplanes, planes, stride=1, downsample=None, use_se=True):
+        super(IRBlock, self).__init__()
+        self.bn0 = nn.BatchNorm2d(inplanes)
+        self.conv1 = conv3x3(inplanes, inplanes)
+        self.bn1 = nn.BatchNorm2d(inplanes)
+        self.prelu = nn.PReLU()
+        self.conv2 = conv3x3(inplanes, planes, stride)
+        self.bn2 = nn.BatchNorm2d(planes)
+        self.downsample = downsample
+        self.stride = stride
+        self.use_se = use_se
+        if self.use_se:
+            self.se = SEBlock(planes)
+
+    def forward(self, x):
+        residual = x
+        out = self.bn0(x)
+        out = self.conv1(out)
+        out = self.bn1(out)
+        out = self.prelu(out)
+
+        out = self.conv2(out)
+        out = self.bn2(out)
+        if self.use_se:
+            out = self.se(out)
+
+        if self.downsample is not None:
+            residual = self.downsample(x)
+
+        out += residual
+        out = self.prelu(out)
+
+        return out
+
+
+class Bottleneck(nn.Module):
+    """Bottleneck block used in the ResNetArcFace architecture.
+
+    Args:
+        inplanes (int): Channel number of inputs.
+        planes (int): Channel number of outputs.
+        stride (int): Stride in convolution. Default: 1.
+        downsample (nn.Module): The downsample module. Default: None.
+    """
+    expansion = 4  # output channel expansion ratio
+
+    def __init__(self, inplanes, planes, stride=1, downsample=None):
+        super(Bottleneck, self).__init__()
+        self.conv1 = nn.Conv2d(inplanes, planes, kernel_size=1, bias=False)
+        self.bn1 = nn.BatchNorm2d(planes)
+        self.conv2 = nn.Conv2d(planes, planes, kernel_size=3, stride=stride, padding=1, bias=False)
+        self.bn2 = nn.BatchNorm2d(planes)
+        self.conv3 = nn.Conv2d(planes, planes * self.expansion, kernel_size=1, bias=False)
+        self.bn3 = nn.BatchNorm2d(planes * self.expansion)
+        self.relu = nn.ReLU(inplace=True)
+        self.downsample = downsample
+        self.stride = stride
+
+    def forward(self, x):
+        residual = x
+
+        out = self.conv1(x)
+        out = self.bn1(out)
+        out = self.relu(out)
+
+        out = self.conv2(out)
+        out = self.bn2(out)
+        out = self.relu(out)
+
+        out = self.conv3(out)
+        out = self.bn3(out)
+
+        if self.downsample is not None:
+            residual = self.downsample(x)
+
+        out += residual
+        out = self.relu(out)
+
+        return out
+
+
+class SEBlock(nn.Module):
+    """The squeeze-and-excitation block (SEBlock) used in the IRBlock.
+
+    Args:
+        channel (int): Channel number of inputs.
+        reduction (int): Channel reduction ration. Default: 16.
+    """
+
+    def __init__(self, channel, reduction=16):
+        super(SEBlock, self).__init__()
+        self.avg_pool = nn.AdaptiveAvgPool2d(1)  # pool to 1x1 without spatial information
+        self.fc = nn.Sequential(
+            nn.Linear(channel, channel // reduction), nn.PReLU(), nn.Linear(channel // reduction, channel),
+            nn.Sigmoid())
+
+    def forward(self, x):
+        b, c, _, _ = x.size()
+        y = self.avg_pool(x).view(b, c)
+        y = self.fc(y).view(b, c, 1, 1)
+        return x * y
+
+
+@ARCH_REGISTRY.register()
+class ResNetArcFace(nn.Module):
+    """ArcFace with ResNet architectures.
+
+    Ref: ArcFace: Additive Angular Margin Loss for Deep Face Recognition.
+
+    Args:
+        block (str): Block used in the ArcFace architecture.
+        layers (tuple(int)): Block numbers in each layer.
+        use_se (bool): Whether use the SEBlock (squeeze and excitation block). Default: True.
+    """
+
+    def __init__(self, block, layers, use_se=True):
+        if block == 'IRBlock':
+            block = IRBlock
+        self.inplanes = 64
+        self.use_se = use_se
+        super(ResNetArcFace, self).__init__()
+
+        self.conv1 = nn.Conv2d(1, 64, kernel_size=3, padding=1, bias=False)
+        self.bn1 = nn.BatchNorm2d(64)
+        self.prelu = nn.PReLU()
+        self.maxpool = nn.MaxPool2d(kernel_size=2, stride=2)
+        self.layer1 = self._make_layer(block, 64, layers[0])
+        self.layer2 = self._make_layer(block, 128, layers[1], stride=2)
+        self.layer3 = self._make_layer(block, 256, layers[2], stride=2)
+        self.layer4 = self._make_layer(block, 512, layers[3], stride=2)
+        self.bn4 = nn.BatchNorm2d(512)
+        self.dropout = nn.Dropout()
+        self.fc5 = nn.Linear(512 * 8 * 8, 512)
+        self.bn5 = nn.BatchNorm1d(512)
+
+        # initialization
+        for m in self.modules():
+            if isinstance(m, nn.Conv2d):
+                nn.init.xavier_normal_(m.weight)
+            elif isinstance(m, nn.BatchNorm2d) or isinstance(m, nn.BatchNorm1d):
+                nn.init.constant_(m.weight, 1)
+                nn.init.constant_(m.bias, 0)
+            elif isinstance(m, nn.Linear):
+                nn.init.xavier_normal_(m.weight)
+                nn.init.constant_(m.bias, 0)
+
+    def _make_layer(self, block, planes, num_blocks, stride=1):
+        downsample = None
+        if stride != 1 or self.inplanes != planes * block.expansion:
+            downsample = nn.Sequential(
+                nn.Conv2d(self.inplanes, planes * block.expansion, kernel_size=1, stride=stride, bias=False),
+                nn.BatchNorm2d(planes * block.expansion),
+            )
+        layers = []
+        layers.append(block(self.inplanes, planes, stride, downsample, use_se=self.use_se))
+        self.inplanes = planes
+        for _ in range(1, num_blocks):
+            layers.append(block(self.inplanes, planes, use_se=self.use_se))
+
+        return nn.Sequential(*layers)
+
+    def forward(self, x):
+        x = self.conv1(x)
+        x = self.bn1(x)
+        x = self.prelu(x)
+        x = self.maxpool(x)
+
+        x = self.layer1(x)
+        x = self.layer2(x)
+        x = self.layer3(x)
+        x = self.layer4(x)
+        x = self.bn4(x)
+        x = self.dropout(x)
+        x = x.view(x.size(0), -1)
+        x = self.fc5(x)
+        x = self.bn5(x)
+
+        return x

basicsr/archs/arch_util.py

@@ -0,0 +1,318 @@
+import collections.abc
+import math
+import torch
+import torchvision
+import warnings
+from distutils.version import LooseVersion
+from itertools import repeat
+from torch import nn as nn
+from torch.nn import functional as F
+from torch.nn import init as init
+from torch.nn.modules.batchnorm import _BatchNorm
+
+from basicsr.ops.dcn import ModulatedDeformConvPack, modulated_deform_conv
+from basicsr.utils import get_root_logger
+
+
+@torch.no_grad()
+def default_init_weights(module_list, scale=1, bias_fill=0, **kwargs):
+    """Initialize network weights.
+
+    Args:
+        module_list (list[nn.Module] | nn.Module): Modules to be initialized.
+        scale (float): Scale initialized weights, especially for residual
+            blocks. Default: 1.
+        bias_fill (float): The value to fill bias. Default: 0
+        kwargs (dict): Other arguments for initialization function.
+    """
+    if not isinstance(module_list, list):
+        module_list = [module_list]
+    for module in module_list:
+        for m in module.modules():
+            if isinstance(m, nn.Conv2d):
+                init.kaiming_normal_(m.weight, **kwargs)
+                m.weight.data *= scale
+                if m.bias is not None:
+                    m.bias.data.fill_(bias_fill)
+            elif isinstance(m, nn.Linear):
+                init.kaiming_normal_(m.weight, **kwargs)
+                m.weight.data *= scale
+                if m.bias is not None:
+                    m.bias.data.fill_(bias_fill)
+            elif isinstance(m, _BatchNorm):
+                init.constant_(m.weight, 1)
+                if m.bias is not None:
+                    m.bias.data.fill_(bias_fill)
+
+
+def make_layer(basic_block, num_basic_block, **kwarg):
+    """Make layers by stacking the same blocks.
+
+    Args:
+        basic_block (nn.module): nn.module class for basic block.
+        num_basic_block (int): number of blocks.
+
+    Returns:
+        nn.Sequential: Stacked blocks in nn.Sequential.
+    """
+    layers = []
+    for _ in range(num_basic_block):
+        layers.append(basic_block(**kwarg))
+    return nn.Sequential(*layers)
+
+
+class ResidualBlockNoBN(nn.Module):
+    """Residual block without BN.
+
+    It has a style of:
+        ---Conv-ReLU-Conv-+-
+         |________________|
+
+    Args:
+        num_feat (int): Channel number of intermediate features.
+            Default: 64.
+        res_scale (float): Residual scale. Default: 1.
+        pytorch_init (bool): If set to True, use pytorch default init,
+            otherwise, use default_init_weights. Default: False.
+    """
+
+    def __init__(self, num_feat=64, res_scale=1, pytorch_init=False):
+        super(ResidualBlockNoBN, self).__init__()
+        self.res_scale = res_scale
+        self.conv1 = nn.Conv2d(num_feat, num_feat, 3, 1, 1, bias=True)
+        self.conv2 = nn.Conv2d(num_feat, num_feat, 3, 1, 1, bias=True)
+        self.relu = nn.ReLU(inplace=True)
+
+        if not pytorch_init:
+            default_init_weights([self.conv1, self.conv2], 0.1)
+
+    def forward(self, x):
+        identity = x
+        out = self.conv2(self.relu(self.conv1(x)))
+        return identity + out * self.res_scale
+
+
+class Upsample(nn.Sequential):
+    """Upsample module.
+
+    Args:
+        scale (int): Scale factor. Supported scales: 2^n and 3.
+        num_feat (int): Channel number of intermediate features.
+    """
+
+    def __init__(self, scale, num_feat):
+        m = []
+        if (scale & (scale - 1)) == 0:  # scale = 2^n
+            for _ in range(int(math.log(scale, 2))):
+                m.append(nn.Conv2d(num_feat, 4 * num_feat, 3, 1, 1))
+                m.append(nn.PixelShuffle(2))
+        elif scale == 3:
+            m.append(nn.Conv2d(num_feat, 9 * num_feat, 3, 1, 1))
+            m.append(nn.PixelShuffle(3))
+        else:
+            raise ValueError(f'scale {scale} is not supported. Supported scales: 2^n and 3.')
+        super(Upsample, self).__init__(*m)
+
+
+def flow_warp(x, flow, interp_mode='bilinear', padding_mode='zeros', align_corners=True):
+    """Warp an image or feature map with optical flow.
+
+    Args:
+        x (Tensor): Tensor with size (n, c, h, w).
+        flow (Tensor): Tensor with size (n, h, w, 2), normal value.
+        interp_mode (str): 'nearest' or 'bilinear'. Default: 'bilinear'.
+        padding_mode (str): 'zeros' or 'border' or 'reflection'.
+            Default: 'zeros'.
+        align_corners (bool): Before pytorch 1.3, the default value is
+            align_corners=True. After pytorch 1.3, the default value is
+            align_corners=False. Here, we use the True as default.
+
+    Returns:
+        Tensor: Warped image or feature map.
+    """
+    assert x.size()[-2:] == flow.size()[1:3]
+    _, _, h, w = x.size()
+    # create mesh grid
+    grid_y, grid_x = torch.meshgrid(torch.arange(0, h).type_as(x), torch.arange(0, w).type_as(x))
+    grid = torch.stack((grid_x, grid_y), 2).float()  # W(x), H(y), 2
+    grid.requires_grad = False
+
+    vgrid = grid + flow
+    # scale grid to [-1,1]
+    vgrid_x = 2.0 * vgrid[:, :, :, 0] / max(w - 1, 1) - 1.0
+    vgrid_y = 2.0 * vgrid[:, :, :, 1] / max(h - 1, 1) - 1.0
+    vgrid_scaled = torch.stack((vgrid_x, vgrid_y), dim=3)
+    output = F.grid_sample(x, vgrid_scaled, mode=interp_mode, padding_mode=padding_mode, align_corners=align_corners)
+
+    # TODO, what if align_corners=False
+    return output
+
+
+def resize_flow(flow, size_type, sizes, interp_mode='bilinear', align_corners=False):
+    """Resize a flow according to ratio or shape.
+
+    Args:
+        flow (Tensor): Precomputed flow. shape [N, 2, H, W].
+        size_type (str): 'ratio' or 'shape'.
+        sizes (list[int | float]): the ratio for resizing or the final output
+            shape.
+            1) The order of ratio should be [ratio_h, ratio_w]. For
+            downsampling, the ratio should be smaller than 1.0 (i.e., ratio
+            < 1.0). For upsampling, the ratio should be larger than 1.0 (i.e.,
+            ratio > 1.0).
+            2) The order of output_size should be [out_h, out_w].
+        interp_mode (str): The mode of interpolation for resizing.
+            Default: 'bilinear'.
+        align_corners (bool): Whether align corners. Default: False.
+
+    Returns:
+        Tensor: Resized flow.
+    """
+    _, _, flow_h, flow_w = flow.size()
+    if size_type == 'ratio':
+        output_h, output_w = int(flow_h * sizes[0]), int(flow_w * sizes[1])
+    elif size_type == 'shape':
+        output_h, output_w = sizes[0], sizes[1]
+    else:
+        raise ValueError(f'Size type should be ratio or shape, but got type {size_type}.')
+
+    input_flow = flow.clone()
+    ratio_h = output_h / flow_h
+    ratio_w = output_w / flow_w
+    input_flow[:, 0, :, :] *= ratio_w
+    input_flow[:, 1, :, :] *= ratio_h
+    resized_flow = F.interpolate(
+        input=input_flow, size=(output_h, output_w), mode=interp_mode, align_corners=align_corners)
+    return resized_flow
+
+
+# TODO: may write a cpp file
+def pixel_unshuffle(x, scale):
+    """ Pixel unshuffle.
+
+    Args:
+        x (Tensor): Input feature with shape (b, c, hh, hw).
+        scale (int): Downsample ratio.
+
+    Returns:
+        Tensor: the pixel unshuffled feature.
+    """
+    b, c, hh, hw = x.size()
+    out_channel = c * (scale**2)
+    assert hh % scale == 0 and hw % scale == 0
+    h = hh // scale
+    w = hw // scale
+    x_view = x.view(b, c, h, scale, w, scale)
+    return x_view.permute(0, 1, 3, 5, 2, 4).reshape(b, out_channel, h, w)
+
+
+class DCNv2Pack(ModulatedDeformConvPack):
+    """Modulated deformable conv for deformable alignment.
+
+    Different from the official DCNv2Pack, which generates offsets and masks
+    from the preceding features, this DCNv2Pack takes another different
+    features to generate offsets and masks.
+
+    Ref:
+        Delving Deep into Deformable Alignment in Video Super-Resolution.
+    """
+
+    def forward(self, x, feat):
+        out = self.conv_offset(feat)
+        o1, o2, mask = torch.chunk(out, 3, dim=1)
+        offset = torch.cat((o1, o2), dim=1)
+        mask = torch.sigmoid(mask)
+
+        offset_absmean = torch.mean(torch.abs(offset))
+        if offset_absmean > 50:
+            logger = get_root_logger()
+            logger.warning(f'Offset abs mean is {offset_absmean}, larger than 50.')
+
+        if LooseVersion(torchvision.__version__) >= LooseVersion('0.9.0'):
+            return torchvision.ops.deform_conv2d(x, offset, self.weight, self.bias, self.stride, self.padding,
+                                                 self.dilation, mask)
+        else:
+            return modulated_deform_conv(x, offset, mask, self.weight, self.bias, self.stride, self.padding,
+                                         self.dilation, self.groups, self.deformable_groups)
+
+
+def _no_grad_trunc_normal_(tensor, mean, std, a, b):
+    # From: https://github.com/rwightman/pytorch-image-models/blob/master/timm/models/layers/weight_init.py
+    # Cut & paste from PyTorch official master until it's in a few official releases - RW
+    # Method based on https://people.sc.fsu.edu/~jburkardt/presentations/truncated_normal.pdf
+    def norm_cdf(x):
+        # Computes standard normal cumulative distribution function
+        return (1. + math.erf(x / math.sqrt(2.))) / 2.
+
+    if (mean < a - 2 * std) or (mean > b + 2 * std):
+        warnings.warn(
+            'mean is more than 2 std from [a, b] in nn.init.trunc_normal_. '
+            'The distribution of values may be incorrect.',
+            stacklevel=2)
+
+    with torch.no_grad():
+        # Values are generated by using a truncated uniform distribution and
+        # then using the inverse CDF for the normal distribution.
+        # Get upper and lower cdf values
+        low = norm_cdf((a - mean) / std)
+        up = norm_cdf((b - mean) / std)
+
+        # Uniformly fill tensor with values from [low, up], then translate to
+        # [2l-1, 2u-1].
+        tensor.uniform_(2 * low - 1, 2 * up - 1)
+
+        # Use inverse cdf transform for normal distribution to get truncated
+        # standard normal
+        tensor.erfinv_()
+
+        # Transform to proper mean, std
+        tensor.mul_(std * math.sqrt(2.))
+        tensor.add_(mean)
+
+        # Clamp to ensure it's in the proper range
+        tensor.clamp_(min=a, max=b)
+        return tensor
+
+
+def trunc_normal_(tensor, mean=0., std=1., a=-2., b=2.):
+    r"""Fills the input Tensor with values drawn from a truncated
+    normal distribution.
+
+    From: https://github.com/rwightman/pytorch-image-models/blob/master/timm/models/layers/weight_init.py
+
+    The values are effectively drawn from the
+    normal distribution :math:`\mathcal{N}(\text{mean}, \text{std}^2)`
+    with values outside :math:`[a, b]` redrawn until they are within
+    the bounds. The method used for generating the random values works
+    best when :math:`a \leq \text{mean} \leq b`.
+
+    Args:
+        tensor: an n-dimensional `torch.Tensor`
+        mean: the mean of the normal distribution
+        std: the standard deviation of the normal distribution
+        a: the minimum cutoff value
+        b: the maximum cutoff value
+
+    Examples:
+        >>> w = torch.empty(3, 5)
+        >>> nn.init.trunc_normal_(w)
+    """
+    return _no_grad_trunc_normal_(tensor, mean, std, a, b)
+
+
+# From PyTorch
+def _ntuple(n):
+
+    def parse(x):
+        if isinstance(x, collections.abc.Iterable):
+            return x
+        return tuple(repeat(x, n))
+
+    return parse
+
+
+to_1tuple = _ntuple(1)
+to_2tuple = _ntuple(2)
+to_3tuple = _ntuple(3)
+to_4tuple = _ntuple(4)
+to_ntuple = _ntuple

basicsr/archs/codeformer_arch.py

@@ -0,0 +1,280 @@
+import math
+import numpy as np
+import torch
+from torch import nn, Tensor
+import torch.nn.functional as F
+from typing import Optional, List
+
+from basicsr.archs.vqgan_arch import *
+from basicsr.utils import get_root_logger
+from basicsr.utils.registry import ARCH_REGISTRY
+
+def calc_mean_std(feat, eps=1e-5):
+    """Calculate mean and std for adaptive_instance_normalization.
+
+    Args:
+        feat (Tensor): 4D tensor.
+        eps (float): A small value added to the variance to avoid
+            divide-by-zero. Default: 1e-5.
+    """
+    size = feat.size()
+    assert len(size) == 4, 'The input feature should be 4D tensor.'
+    b, c = size[:2]
+    feat_var = feat.view(b, c, -1).var(dim=2) + eps
+    feat_std = feat_var.sqrt().view(b, c, 1, 1)
+    feat_mean = feat.view(b, c, -1).mean(dim=2).view(b, c, 1, 1)
+    return feat_mean, feat_std
+
+
+def adaptive_instance_normalization(content_feat, style_feat):
+    """Adaptive instance normalization.
+
+    Adjust the reference features to have the similar color and illuminations
+    as those in the degradate features.
+
+    Args:
+        content_feat (Tensor): The reference feature.
+        style_feat (Tensor): The degradate features.
+    """
+    size = content_feat.size()
+    style_mean, style_std = calc_mean_std(style_feat)
+    content_mean, content_std = calc_mean_std(content_feat)
+    normalized_feat = (content_feat - content_mean.expand(size)) / content_std.expand(size)
+    return normalized_feat * style_std.expand(size) + style_mean.expand(size)
+
+
+class PositionEmbeddingSine(nn.Module):
+    """
+    This is a more standard version of the position embedding, very similar to the one
+    used by the Attention is all you need paper, generalized to work on images.
+    """
+
+    def __init__(self, num_pos_feats=64, temperature=10000, normalize=False, scale=None):
+        super().__init__()
+        self.num_pos_feats = num_pos_feats
+        self.temperature = temperature
+        self.normalize = normalize
+        if scale is not None and normalize is False:
+            raise ValueError("normalize should be True if scale is passed")
+        if scale is None:
+            scale = 2 * math.pi
+        self.scale = scale
+
+    def forward(self, x, mask=None):
+        if mask is None:
+            mask = torch.zeros((x.size(0), x.size(2), x.size(3)), device=x.device, dtype=torch.bool)
+        not_mask = ~mask
+        y_embed = not_mask.cumsum(1, dtype=torch.float32)
+        x_embed = not_mask.cumsum(2, dtype=torch.float32)
+        if self.normalize:
+            eps = 1e-6
+            y_embed = y_embed / (y_embed[:, -1:, :] + eps) * self.scale
+            x_embed = x_embed / (x_embed[:, :, -1:] + eps) * self.scale
+
+        dim_t = torch.arange(self.num_pos_feats, dtype=torch.float32, device=x.device)
+        dim_t = self.temperature ** (2 * (dim_t // 2) / self.num_pos_feats)
+
+        pos_x = x_embed[:, :, :, None] / dim_t
+        pos_y = y_embed[:, :, :, None] / dim_t
+        pos_x = torch.stack(
+            (pos_x[:, :, :, 0::2].sin(), pos_x[:, :, :, 1::2].cos()), dim=4
+        ).flatten(3)
+        pos_y = torch.stack(
+            (pos_y[:, :, :, 0::2].sin(), pos_y[:, :, :, 1::2].cos()), dim=4
+        ).flatten(3)
+        pos = torch.cat((pos_y, pos_x), dim=3).permute(0, 3, 1, 2)
+        return pos
+
+def _get_activation_fn(activation):
+    """Return an activation function given a string"""
+    if activation == "relu":
+        return F.relu
+    if activation == "gelu":
+        return F.gelu
+    if activation == "glu":
+        return F.glu
+    raise RuntimeError(F"activation should be relu/gelu, not {activation}.")
+
+
+class TransformerSALayer(nn.Module):
+    def __init__(self, embed_dim, nhead=8, dim_mlp=2048, dropout=0.0, activation="gelu"):
+        super().__init__()
+        self.self_attn = nn.MultiheadAttention(embed_dim, nhead, dropout=dropout)
+        # Implementation of Feedforward model - MLP
+        self.linear1 = nn.Linear(embed_dim, dim_mlp)
+        self.dropout = nn.Dropout(dropout)
+        self.linear2 = nn.Linear(dim_mlp, embed_dim)
+
+        self.norm1 = nn.LayerNorm(embed_dim)
+        self.norm2 = nn.LayerNorm(embed_dim)
+        self.dropout1 = nn.Dropout(dropout)
+        self.dropout2 = nn.Dropout(dropout)
+
+        self.activation = _get_activation_fn(activation)
+
+    def with_pos_embed(self, tensor, pos: Optional[Tensor]):
+        return tensor if pos is None else tensor + pos
+
+    def forward(self, tgt,
+                tgt_mask: Optional[Tensor] = None,
+                tgt_key_padding_mask: Optional[Tensor] = None,
+                query_pos: Optional[Tensor] = None):
+        
+        # self attention
+        tgt2 = self.norm1(tgt)
+        q = k = self.with_pos_embed(tgt2, query_pos)
+        tgt2 = self.self_attn(q, k, value=tgt2, attn_mask=tgt_mask,
+                              key_padding_mask=tgt_key_padding_mask)[0]
+        tgt = tgt + self.dropout1(tgt2)
+
+        # ffn
+        tgt2 = self.norm2(tgt)
+        tgt2 = self.linear2(self.dropout(self.activation(self.linear1(tgt2))))
+        tgt = tgt + self.dropout2(tgt2)
+        return tgt
+
+class Fuse_sft_block(nn.Module):
+    def __init__(self, in_ch, out_ch):
+        super().__init__()
+        self.encode_enc = ResBlock(2*in_ch, out_ch)
+
+        self.scale = nn.Sequential(
+                    nn.Conv2d(in_ch, out_ch, kernel_size=3, padding=1),
+                    nn.LeakyReLU(0.2, True),
+                    nn.Conv2d(out_ch, out_ch, kernel_size=3, padding=1))
+
+        self.shift = nn.Sequential(
+                    nn.Conv2d(in_ch, out_ch, kernel_size=3, padding=1),
+                    nn.LeakyReLU(0.2, True),
+                    nn.Conv2d(out_ch, out_ch, kernel_size=3, padding=1))
+
+    def forward(self, enc_feat, dec_feat, w=1):
+        enc_feat = self.encode_enc(torch.cat([enc_feat, dec_feat], dim=1))
+        scale = self.scale(enc_feat)
+        shift = self.shift(enc_feat)
+        residual = w * (dec_feat * scale + shift)
+        out = dec_feat + residual
+        return out
+
+
+@ARCH_REGISTRY.register()
+class CodeFormer(VQAutoEncoder):
+    def __init__(self, dim_embd=512, n_head=8, n_layers=9, 
+                codebook_size=1024, latent_size=256,
+                connect_list=['32', '64', '128', '256'],
+                fix_modules=['quantize','generator'], vqgan_path=None):
+        super(CodeFormer, self).__init__(512, 64, [1, 2, 2, 4, 4, 8], 'nearest',2, [16], codebook_size)
+
+        if vqgan_path is not None:
+            self.load_state_dict(
+                torch.load(vqgan_path, map_location='cpu')['params_ema'])
+
+        if fix_modules is not None:
+            for module in fix_modules:
+                for param in getattr(self, module).parameters():
+                    param.requires_grad = False
+
+        self.connect_list = connect_list
+        self.n_layers = n_layers
+        self.dim_embd = dim_embd
+        self.dim_mlp = dim_embd*2
+
+        self.position_emb = nn.Parameter(torch.zeros(latent_size, self.dim_embd))
+        self.feat_emb = nn.Linear(256, self.dim_embd)
+
+        # transformer
+        self.ft_layers = nn.Sequential(*[TransformerSALayer(embed_dim=dim_embd, nhead=n_head, dim_mlp=self.dim_mlp, dropout=0.0) 
+                                    for _ in range(self.n_layers)])
+
+        # logits_predict head
+        self.idx_pred_layer = nn.Sequential(
+            nn.LayerNorm(dim_embd),
+            nn.Linear(dim_embd, codebook_size, bias=False))
+        
+        self.channels = {
+            '16': 512,
+            '32': 256,
+            '64': 256,
+            '128': 128,
+            '256': 128,
+            '512': 64,
+        }
+
+        # after second residual block for > 16, before attn layer for ==16
+        self.fuse_encoder_block = {'512':2, '256':5, '128':8, '64':11, '32':14, '16':18}
+        # after first residual block for > 16, before attn layer for ==16
+        self.fuse_generator_block = {'16':6, '32': 9, '64':12, '128':15, '256':18, '512':21}
+
+        # fuse_convs_dict
+        self.fuse_convs_dict = nn.ModuleDict()
+        for f_size in self.connect_list:
+            in_ch = self.channels[f_size]
+            self.fuse_convs_dict[f_size] = Fuse_sft_block(in_ch, in_ch)
+
+    def _init_weights(self, module):
+        if isinstance(module, (nn.Linear, nn.Embedding)):
+            module.weight.data.normal_(mean=0.0, std=0.02)
+            if isinstance(module, nn.Linear) and module.bias is not None:
+                module.bias.data.zero_()
+        elif isinstance(module, nn.LayerNorm):
+            module.bias.data.zero_()
+            module.weight.data.fill_(1.0)
+
+    def forward(self, x, w=0, detach_16=True, code_only=False, adain=False):
+        # ################### Encoder #####################
+        enc_feat_dict = {}
+        out_list = [self.fuse_encoder_block[f_size] for f_size in self.connect_list]
+        for i, block in enumerate(self.encoder.blocks):
+            x = block(x) 
+            if i in out_list:
+                enc_feat_dict[str(x.shape[-1])] = x.clone()
+
+        lq_feat = x
+        # ################# Transformer ###################
+        # quant_feat, codebook_loss, quant_stats = self.quantize(lq_feat)
+        pos_emb = self.position_emb.unsqueeze(1).repeat(1,x.shape[0],1)
+        # BCHW -> BC(HW) -> (HW)BC
+        feat_emb = self.feat_emb(lq_feat.flatten(2).permute(2,0,1))
+        query_emb = feat_emb
+        # Transformer encoder
+        for layer in self.ft_layers:
+            query_emb = layer(query_emb, query_pos=pos_emb)
+
+        # output logits
+        logits = self.idx_pred_layer(query_emb) # (hw)bn
+        logits = logits.permute(1,0,2) # (hw)bn -> b(hw)n
+
+        if code_only: # for training stage II
+          # logits doesn't need softmax before cross_entropy loss
+            return logits, lq_feat
+
+        # ################# Quantization ###################
+        # if self.training:
+        #     quant_feat = torch.einsum('btn,nc->btc', [soft_one_hot, self.quantize.embedding.weight])
+        #     # b(hw)c -> bc(hw) -> bchw
+        #     quant_feat = quant_feat.permute(0,2,1).view(lq_feat.shape)
+        # ------------
+        soft_one_hot = F.softmax(logits, dim=2)
+        _, top_idx = torch.topk(soft_one_hot, 1, dim=2)
+        quant_feat = self.quantize.get_codebook_feat(top_idx, shape=[x.shape[0],16,16,256])
+        # preserve gradients
+        # quant_feat = lq_feat + (quant_feat - lq_feat).detach()
+
+        if detach_16:
+            quant_feat = quant_feat.detach() # for training stage III
+        if adain:
+            quant_feat = adaptive_instance_normalization(quant_feat, lq_feat)
+
+        # ################## Generator ####################
+        x = quant_feat
+        fuse_list = [self.fuse_generator_block[f_size] for f_size in self.connect_list]
+
+        for i, block in enumerate(self.generator.blocks):
+            x = block(x) 
+            if i in fuse_list: # fuse after i-th block
+                f_size = str(x.shape[-1])
+                if w>0:
+                    x = self.fuse_convs_dict[f_size](enc_feat_dict[f_size].detach(), x, w)
+        out = x
+        # logits doesn't need softmax before cross_entropy loss
+        return out, logits, lq_feat

basicsr/archs/rrdbnet_arch.py

@@ -0,0 +1,119 @@
+import torch
+from torch import nn as nn
+from torch.nn import functional as F
+
+from basicsr.utils.registry import ARCH_REGISTRY
+from .arch_util import default_init_weights, make_layer, pixel_unshuffle
+
+
+class ResidualDenseBlock(nn.Module):
+    """Residual Dense Block.
+
+    Used in RRDB block in ESRGAN.
+
+    Args:
+        num_feat (int): Channel number of intermediate features.
+        num_grow_ch (int): Channels for each growth.
+    """
+
+    def __init__(self, num_feat=64, num_grow_ch=32):
+        super(ResidualDenseBlock, self).__init__()
+        self.conv1 = nn.Conv2d(num_feat, num_grow_ch, 3, 1, 1)
+        self.conv2 = nn.Conv2d(num_feat + num_grow_ch, num_grow_ch, 3, 1, 1)
+        self.conv3 = nn.Conv2d(num_feat + 2 * num_grow_ch, num_grow_ch, 3, 1, 1)
+        self.conv4 = nn.Conv2d(num_feat + 3 * num_grow_ch, num_grow_ch, 3, 1, 1)
+        self.conv5 = nn.Conv2d(num_feat + 4 * num_grow_ch, num_feat, 3, 1, 1)
+
+        self.lrelu = nn.LeakyReLU(negative_slope=0.2, inplace=True)
+
+        # initialization
+        default_init_weights([self.conv1, self.conv2, self.conv3, self.conv4, self.conv5], 0.1)
+
+    def forward(self, x):
+        x1 = self.lrelu(self.conv1(x))
+        x2 = self.lrelu(self.conv2(torch.cat((x, x1), 1)))
+        x3 = self.lrelu(self.conv3(torch.cat((x, x1, x2), 1)))
+        x4 = self.lrelu(self.conv4(torch.cat((x, x1, x2, x3), 1)))
+        x5 = self.conv5(torch.cat((x, x1, x2, x3, x4), 1))
+        # Emperically, we use 0.2 to scale the residual for better performance
+        return x5 * 0.2 + x
+
+
+class RRDB(nn.Module):
+    """Residual in Residual Dense Block.
+
+    Used in RRDB-Net in ESRGAN.
+
+    Args:
+        num_feat (int): Channel number of intermediate features.
+        num_grow_ch (int): Channels for each growth.
+    """
+
+    def __init__(self, num_feat, num_grow_ch=32):
+        super(RRDB, self).__init__()
+        self.rdb1 = ResidualDenseBlock(num_feat, num_grow_ch)
+        self.rdb2 = ResidualDenseBlock(num_feat, num_grow_ch)
+        self.rdb3 = ResidualDenseBlock(num_feat, num_grow_ch)
+
+    def forward(self, x):
+        out = self.rdb1(x)
+        out = self.rdb2(out)
+        out = self.rdb3(out)
+        # Emperically, we use 0.2 to scale the residual for better performance
+        return out * 0.2 + x
+
+
+@ARCH_REGISTRY.register()
+class RRDBNet(nn.Module):
+    """Networks consisting of Residual in Residual Dense Block, which is used
+    in ESRGAN.
+
+    ESRGAN: Enhanced Super-Resolution Generative Adversarial Networks.
+
+    We extend ESRGAN for scale x2 and scale x1.
+    Note: This is one option for scale 1, scale 2 in RRDBNet.
+    We first employ the pixel-unshuffle (an inverse operation of pixelshuffle to reduce the spatial size
+    and enlarge the channel size before feeding inputs into the main ESRGAN architecture.
+
+    Args:
+        num_in_ch (int): Channel number of inputs.
+        num_out_ch (int): Channel number of outputs.
+        num_feat (int): Channel number of intermediate features.
+            Default: 64
+        num_block (int): Block number in the trunk network. Defaults: 23
+        num_grow_ch (int): Channels for each growth. Default: 32.
+    """
+
+    def __init__(self, num_in_ch, num_out_ch, scale=4, num_feat=64, num_block=23, num_grow_ch=32):
+        super(RRDBNet, self).__init__()
+        self.scale = scale
+        if scale == 2:
+            num_in_ch = num_in_ch * 4
+        elif scale == 1:
+            num_in_ch = num_in_ch * 16
+        self.conv_first = nn.Conv2d(num_in_ch, num_feat, 3, 1, 1)
+        self.body = make_layer(RRDB, num_block, num_feat=num_feat, num_grow_ch=num_grow_ch)
+        self.conv_body = nn.Conv2d(num_feat, num_feat, 3, 1, 1)
+        # upsample
+        self.conv_up1 = nn.Conv2d(num_feat, num_feat, 3, 1, 1)
+        self.conv_up2 = nn.Conv2d(num_feat, num_feat, 3, 1, 1)
+        self.conv_hr = nn.Conv2d(num_feat, num_feat, 3, 1, 1)
+        self.conv_last = nn.Conv2d(num_feat, num_out_ch, 3, 1, 1)
+
+        self.lrelu = nn.LeakyReLU(negative_slope=0.2, inplace=True)
+
+    def forward(self, x):
+        if self.scale == 2:
+            feat = pixel_unshuffle(x, scale=2)
+        elif self.scale == 1:
+            feat = pixel_unshuffle(x, scale=4)
+        else:
+            feat = x
+        feat = self.conv_first(feat)
+        body_feat = self.conv_body(self.body(feat))
+        feat = feat + body_feat
+        # upsample
+        feat = self.lrelu(self.conv_up1(F.interpolate(feat, scale_factor=2, mode='nearest')))
+        feat = self.lrelu(self.conv_up2(F.interpolate(feat, scale_factor=2, mode='nearest')))
+        out = self.conv_last(self.lrelu(self.conv_hr(feat)))
+        return out

basicsr/archs/vgg_arch.py

@@ -0,0 +1,161 @@
+import os
+import torch
+from collections import OrderedDict
+from torch import nn as nn
+from torchvision.models import vgg as vgg
+
+from basicsr.utils.registry import ARCH_REGISTRY
+
+VGG_PRETRAIN_PATH = 'experiments/pretrained_models/vgg19-dcbb9e9d.pth'
+NAMES = {
+    'vgg11': [
+        'conv1_1', 'relu1_1', 'pool1', 'conv2_1', 'relu2_1', 'pool2', 'conv3_1', 'relu3_1', 'conv3_2', 'relu3_2',
+        'pool3', 'conv4_1', 'relu4_1', 'conv4_2', 'relu4_2', 'pool4', 'conv5_1', 'relu5_1', 'conv5_2', 'relu5_2',
+        'pool5'
+    ],
+    'vgg13': [
+        'conv1_1', 'relu1_1', 'conv1_2', 'relu1_2', 'pool1', 'conv2_1', 'relu2_1', 'conv2_2', 'relu2_2', 'pool2',
+        'conv3_1', 'relu3_1', 'conv3_2', 'relu3_2', 'pool3', 'conv4_1', 'relu4_1', 'conv4_2', 'relu4_2', 'pool4',
+        'conv5_1', 'relu5_1', 'conv5_2', 'relu5_2', 'pool5'
+    ],
+    'vgg16': [
+        'conv1_1', 'relu1_1', 'conv1_2', 'relu1_2', 'pool1', 'conv2_1', 'relu2_1', 'conv2_2', 'relu2_2', 'pool2',
+        'conv3_1', 'relu3_1', 'conv3_2', 'relu3_2', 'conv3_3', 'relu3_3', 'pool3', 'conv4_1', 'relu4_1', 'conv4_2',
+        'relu4_2', 'conv4_3', 'relu4_3', 'pool4', 'conv5_1', 'relu5_1', 'conv5_2', 'relu5_2', 'conv5_3', 'relu5_3',
+        'pool5'
+    ],
+    'vgg19': [
+        'conv1_1', 'relu1_1', 'conv1_2', 'relu1_2', 'pool1', 'conv2_1', 'relu2_1', 'conv2_2', 'relu2_2', 'pool2',
+        'conv3_1', 'relu3_1', 'conv3_2', 'relu3_2', 'conv3_3', 'relu3_3', 'conv3_4', 'relu3_4', 'pool3', 'conv4_1',
+        'relu4_1', 'conv4_2', 'relu4_2', 'conv4_3', 'relu4_3', 'conv4_4', 'relu4_4', 'pool4', 'conv5_1', 'relu5_1',
+        'conv5_2', 'relu5_2', 'conv5_3', 'relu5_3', 'conv5_4', 'relu5_4', 'pool5'
+    ]
+}
+
+
+def insert_bn(names):
+    """Insert bn layer after each conv.
+
+    Args:
+        names (list): The list of layer names.
+
+    Returns:
+        list: The list of layer names with bn layers.
+    """
+    names_bn = []
+    for name in names:
+        names_bn.append(name)
+        if 'conv' in name:
+            position = name.replace('conv', '')
+            names_bn.append('bn' + position)
+    return names_bn
+
+
+@ARCH_REGISTRY.register()
+class VGGFeatureExtractor(nn.Module):
+    """VGG network for feature extraction.
+
+    In this implementation, we allow users to choose whether use normalization
+    in the input feature and the type of vgg network. Note that the pretrained
+    path must fit the vgg type.
+
+    Args:
+        layer_name_list (list[str]): Forward function returns the corresponding
+            features according to the layer_name_list.
+            Example: {'relu1_1', 'relu2_1', 'relu3_1'}.
+        vgg_type (str): Set the type of vgg network. Default: 'vgg19'.
+        use_input_norm (bool): If True, normalize the input image. Importantly,
+            the input feature must in the range [0, 1]. Default: True.
+        range_norm (bool): If True, norm images with range [-1, 1] to [0, 1].
+            Default: False.
+        requires_grad (bool): If true, the parameters of VGG network will be
+            optimized. Default: False.
+        remove_pooling (bool): If true, the max pooling operations in VGG net
+            will be removed. Default: False.
+        pooling_stride (int): The stride of max pooling operation. Default: 2.
+    """
+
+    def __init__(self,
+                 layer_name_list,
+                 vgg_type='vgg19',
+                 use_input_norm=True,
+                 range_norm=False,
+                 requires_grad=False,
+                 remove_pooling=False,
+                 pooling_stride=2):
+        super(VGGFeatureExtractor, self).__init__()
+
+        self.layer_name_list = layer_name_list
+        self.use_input_norm = use_input_norm
+        self.range_norm = range_norm
+
+        self.names = NAMES[vgg_type.replace('_bn', '')]
+        if 'bn' in vgg_type:
+            self.names = insert_bn(self.names)
+
+        # only borrow layers that will be used to avoid unused params
+        max_idx = 0
+        for v in layer_name_list:
+            idx = self.names.index(v)
+            if idx > max_idx:
+                max_idx = idx
+
+        if os.path.exists(VGG_PRETRAIN_PATH):
+            vgg_net = getattr(vgg, vgg_type)(pretrained=False)
+            state_dict = torch.load(VGG_PRETRAIN_PATH, map_location=lambda storage, loc: storage)
+            vgg_net.load_state_dict(state_dict)
+        else:
+            vgg_net = getattr(vgg, vgg_type)(pretrained=True)
+
+        features = vgg_net.features[:max_idx + 1]
+
+        modified_net = OrderedDict()
+        for k, v in zip(self.names, features):
+            if 'pool' in k:
+                # if remove_pooling is true, pooling operation will be removed
+                if remove_pooling:
+                    continue
+                else:
+                    # in some cases, we may want to change the default stride
+                    modified_net[k] = nn.MaxPool2d(kernel_size=2, stride=pooling_stride)
+            else:
+                modified_net[k] = v
+
+        self.vgg_net = nn.Sequential(modified_net)
+
+        if not requires_grad:
+            self.vgg_net.eval()
+            for param in self.parameters():
+                param.requires_grad = False
+        else:
+            self.vgg_net.train()
+            for param in self.parameters():
+                param.requires_grad = True
+
+        if self.use_input_norm:
+            # the mean is for image with range [0, 1]
+            self.register_buffer('mean', torch.Tensor([0.485, 0.456, 0.406]).view(1, 3, 1, 1))
+            # the std is for image with range [0, 1]
+            self.register_buffer('std', torch.Tensor([0.229, 0.224, 0.225]).view(1, 3, 1, 1))
+
+    def forward(self, x):
+        """Forward function.
+
+        Args:
+            x (Tensor): Input tensor with shape (n, c, h, w).
+
+        Returns:
+            Tensor: Forward results.
+        """
+        if self.range_norm:
+            x = (x + 1) / 2
+        if self.use_input_norm:
+            x = (x - self.mean) / self.std
+        output = {}
+
+        for key, layer in self.vgg_net._modules.items():
+            x = layer(x)
+            if key in self.layer_name_list:
+                output[key] = x.clone()
+
+        return output

basicsr/archs/vqgan_arch.py

@@ -0,0 +1,434 @@
+'''
+VQGAN code, adapted from the original created by the Unleashing Transformers authors:
+https://github.com/samb-t/unleashing-transformers/blob/master/models/vqgan.py
+
+'''
+import numpy as np
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+import copy
+from basicsr.utils import get_root_logger
+from basicsr.utils.registry import ARCH_REGISTRY
+
+def normalize(in_channels):
+    return torch.nn.GroupNorm(num_groups=32, num_channels=in_channels, eps=1e-6, affine=True)
+    
+
+@torch.jit.script
+def swish(x):
+    return x*torch.sigmoid(x)
+
+
+#  Define VQVAE classes
+class VectorQuantizer(nn.Module):
+    def __init__(self, codebook_size, emb_dim, beta):
+        super(VectorQuantizer, self).__init__()
+        self.codebook_size = codebook_size  # number of embeddings
+        self.emb_dim = emb_dim  # dimension of embedding
+        self.beta = beta  # commitment cost used in loss term, beta * ||z_e(x)-sg[e]||^2
+        self.embedding = nn.Embedding(self.codebook_size, self.emb_dim)
+        self.embedding.weight.data.uniform_(-1.0 / self.codebook_size, 1.0 / self.codebook_size)
+
+    def forward(self, z):
+        # reshape z -> (batch, height, width, channel) and flatten
+        z = z.permute(0, 2, 3, 1).contiguous()
+        z_flattened = z.view(-1, self.emb_dim)
+
+        # distances from z to embeddings e_j (z - e)^2 = z^2 + e^2 - 2 e * z
+        d = (z_flattened ** 2).sum(dim=1, keepdim=True) + (self.embedding.weight**2).sum(1) - \
+            2 * torch.matmul(z_flattened, self.embedding.weight.t())
+
+        mean_distance = torch.mean(d)
+        # find closest encodings
+        min_encoding_indices = torch.argmin(d, dim=1).unsqueeze(1)
+        # min_encoding_scores, min_encoding_indices = torch.topk(d, 1, dim=1, largest=False)
+        # [0-1], higher score, higher confidence
+        # min_encoding_scores = torch.exp(-min_encoding_scores/10)
+
+        min_encodings = torch.zeros(min_encoding_indices.shape[0], self.codebook_size).to(z)
+        min_encodings.scatter_(1, min_encoding_indices, 1)
+
+        # get quantized latent vectors
+        z_q = torch.matmul(min_encodings, self.embedding.weight).view(z.shape)
+        # compute loss for embedding
+        loss = torch.mean((z_q.detach()-z)**2) + self.beta * torch.mean((z_q - z.detach()) ** 2)
+        # preserve gradients
+        z_q = z + (z_q - z).detach()
+
+        # perplexity
+        e_mean = torch.mean(min_encodings, dim=0)
+        perplexity = torch.exp(-torch.sum(e_mean * torch.log(e_mean + 1e-10)))
+        # reshape back to match original input shape
+        z_q = z_q.permute(0, 3, 1, 2).contiguous()
+
+        return z_q, loss, {
+            "perplexity": perplexity,
+            "min_encodings": min_encodings,
+            "min_encoding_indices": min_encoding_indices,
+            "mean_distance": mean_distance
+            }
+
+    def get_codebook_feat(self, indices, shape):
+        # input indices: batch*token_num -> (batch*token_num)*1
+        # shape: batch, height, width, channel
+        indices = indices.view(-1,1)
+        min_encodings = torch.zeros(indices.shape[0], self.codebook_size).to(indices)
+        min_encodings.scatter_(1, indices, 1)
+        # get quantized latent vectors
+        z_q = torch.matmul(min_encodings.float(), self.embedding.weight)
+
+        if shape is not None:  # reshape back to match original input shape
+            z_q = z_q.view(shape).permute(0, 3, 1, 2).contiguous()
+
+        return z_q
+
+
+class GumbelQuantizer(nn.Module):
+    def __init__(self, codebook_size, emb_dim, num_hiddens, straight_through=False, kl_weight=5e-4, temp_init=1.0):
+        super().__init__()
+        self.codebook_size = codebook_size  # number of embeddings
+        self.emb_dim = emb_dim  # dimension of embedding
+        self.straight_through = straight_through
+        self.temperature = temp_init
+        self.kl_weight = kl_weight
+        self.proj = nn.Conv2d(num_hiddens, codebook_size, 1)  # projects last encoder layer to quantized logits
+        self.embed = nn.Embedding(codebook_size, emb_dim)
+
+    def forward(self, z):
+        hard = self.straight_through if self.training else True
+
+        logits = self.proj(z)
+
+        soft_one_hot = F.gumbel_softmax(logits, tau=self.temperature, dim=1, hard=hard)
+
+        z_q = torch.einsum("b n h w, n d -> b d h w", soft_one_hot, self.embed.weight)
+
+        # + kl divergence to the prior loss
+        qy = F.softmax(logits, dim=1)
+        diff = self.kl_weight * torch.sum(qy * torch.log(qy * self.codebook_size + 1e-10), dim=1).mean()
+        min_encoding_indices = soft_one_hot.argmax(dim=1)
+
+        return z_q, diff, {
+            "min_encoding_indices": min_encoding_indices
+        }
+
+
+class Downsample(nn.Module):
+    def __init__(self, in_channels):
+        super().__init__()
+        self.conv = torch.nn.Conv2d(in_channels, in_channels, kernel_size=3, stride=2, padding=0)
+
+    def forward(self, x):
+        pad = (0, 1, 0, 1)
+        x = torch.nn.functional.pad(x, pad, mode="constant", value=0)
+        x = self.conv(x)
+        return x
+
+
+class Upsample(nn.Module):
+    def __init__(self, in_channels):
+        super().__init__()
+        self.conv = nn.Conv2d(in_channels, in_channels, kernel_size=3, stride=1, padding=1)
+
+    def forward(self, x):
+        x = F.interpolate(x, scale_factor=2.0, mode="nearest")
+        x = self.conv(x)
+
+        return x
+
+
+class ResBlock(nn.Module):
+    def __init__(self, in_channels, out_channels=None):
+        super(ResBlock, self).__init__()
+        self.in_channels = in_channels
+        self.out_channels = in_channels if out_channels is None else out_channels
+        self.norm1 = normalize(in_channels)
+        self.conv1 = nn.Conv2d(in_channels, out_channels, kernel_size=3, stride=1, padding=1)
+        self.norm2 = normalize(out_channels)
+        self.conv2 = nn.Conv2d(out_channels, out_channels, kernel_size=3, stride=1, padding=1)
+        if self.in_channels != self.out_channels:
+            self.conv_out = nn.Conv2d(in_channels, out_channels, kernel_size=1, stride=1, padding=0)
+
+    def forward(self, x_in):
+        x = x_in
+        x = self.norm1(x)
+        x = swish(x)
+        x = self.conv1(x)
+        x = self.norm2(x)
+        x = swish(x)
+        x = self.conv2(x)
+        if self.in_channels != self.out_channels:
+            x_in = self.conv_out(x_in)
+
+        return x + x_in
+
+
+class AttnBlock(nn.Module):
+    def __init__(self, in_channels):
+        super().__init__()
+        self.in_channels = in_channels
+
+        self.norm = normalize(in_channels)
+        self.q = torch.nn.Conv2d(
+            in_channels,
+            in_channels,
+            kernel_size=1,
+            stride=1,
+            padding=0
+        )
+        self.k = torch.nn.Conv2d(
+            in_channels,
+            in_channels,
+            kernel_size=1,
+            stride=1,
+            padding=0
+        )
+        self.v = torch.nn.Conv2d(
+            in_channels,
+            in_channels,
+            kernel_size=1,
+            stride=1,
+            padding=0
+        )
+        self.proj_out = torch.nn.Conv2d(
+            in_channels,
+            in_channels,
+            kernel_size=1,
+            stride=1,
+            padding=0
+        )
+
+    def forward(self, x):
+        h_ = x
+        h_ = self.norm(h_)
+        q = self.q(h_)
+        k = self.k(h_)
+        v = self.v(h_)
+
+        # compute attention
+        b, c, h, w = q.shape
+        q = q.reshape(b, c, h*w)
+        q = q.permute(0, 2, 1)   
+        k = k.reshape(b, c, h*w)
+        w_ = torch.bmm(q, k) 
+        w_ = w_ * (int(c)**(-0.5))
+        w_ = F.softmax(w_, dim=2)
+
+        # attend to values
+        v = v.reshape(b, c, h*w)
+        w_ = w_.permute(0, 2, 1) 
+        h_ = torch.bmm(v, w_)
+        h_ = h_.reshape(b, c, h, w)
+
+        h_ = self.proj_out(h_)
+
+        return x+h_
+
+
+class Encoder(nn.Module):
+    def __init__(self, in_channels, nf, emb_dim, ch_mult, num_res_blocks, resolution, attn_resolutions):
+        super().__init__()
+        self.nf = nf
+        self.num_resolutions = len(ch_mult)
+        self.num_res_blocks = num_res_blocks
+        self.resolution = resolution
+        self.attn_resolutions = attn_resolutions
+
+        curr_res = self.resolution
+        in_ch_mult = (1,)+tuple(ch_mult)
+
+        blocks = []
+        # initial convultion
+        blocks.append(nn.Conv2d(in_channels, nf, kernel_size=3, stride=1, padding=1))
+
+        # residual and downsampling blocks, with attention on smaller res (16x16)
+        for i in range(self.num_resolutions):
+            block_in_ch = nf * in_ch_mult[i]
+            block_out_ch = nf * ch_mult[i]
+            for _ in range(self.num_res_blocks):
+                blocks.append(ResBlock(block_in_ch, block_out_ch))
+                block_in_ch = block_out_ch
+                if curr_res in attn_resolutions:
+                    blocks.append(AttnBlock(block_in_ch))
+
+            if i != self.num_resolutions - 1:
+                blocks.append(Downsample(block_in_ch))
+                curr_res = curr_res // 2
+
+        # non-local attention block
+        blocks.append(ResBlock(block_in_ch, block_in_ch))
+        blocks.append(AttnBlock(block_in_ch))
+        blocks.append(ResBlock(block_in_ch, block_in_ch))
+
+        # normalise and convert to latent size
+        blocks.append(normalize(block_in_ch))
+        blocks.append(nn.Conv2d(block_in_ch, emb_dim, kernel_size=3, stride=1, padding=1))
+        self.blocks = nn.ModuleList(blocks)
+
+    def forward(self, x):
+        for block in self.blocks:
+            x = block(x)
+            
+        return x
+
+
+class Generator(nn.Module):
+    def __init__(self, nf, emb_dim, ch_mult, res_blocks, img_size, attn_resolutions):
+        super().__init__()
+        self.nf = nf 
+        self.ch_mult = ch_mult 
+        self.num_resolutions = len(self.ch_mult)
+        self.num_res_blocks = res_blocks
+        self.resolution = img_size 
+        self.attn_resolutions = attn_resolutions
+        self.in_channels = emb_dim
+        self.out_channels = 3
+        block_in_ch = self.nf * self.ch_mult[-1]
+        curr_res = self.resolution // 2 ** (self.num_resolutions-1)
+
+        blocks = []
+        # initial conv
+        blocks.append(nn.Conv2d(self.in_channels, block_in_ch, kernel_size=3, stride=1, padding=1))
+
+        # non-local attention block
+        blocks.append(ResBlock(block_in_ch, block_in_ch))
+        blocks.append(AttnBlock(block_in_ch))
+        blocks.append(ResBlock(block_in_ch, block_in_ch))
+
+        for i in reversed(range(self.num_resolutions)):
+            block_out_ch = self.nf * self.ch_mult[i]
+
+            for _ in range(self.num_res_blocks):
+                blocks.append(ResBlock(block_in_ch, block_out_ch))
+                block_in_ch = block_out_ch
+
+                if curr_res in self.attn_resolutions:
+                    blocks.append(AttnBlock(block_in_ch))
+
+            if i != 0:
+                blocks.append(Upsample(block_in_ch))
+                curr_res = curr_res * 2
+
+        blocks.append(normalize(block_in_ch))
+        blocks.append(nn.Conv2d(block_in_ch, self.out_channels, kernel_size=3, stride=1, padding=1))
+
+        self.blocks = nn.ModuleList(blocks)
+   
+
+    def forward(self, x):
+        for block in self.blocks:
+            x = block(x)
+            
+        return x
+
+  
+@ARCH_REGISTRY.register()
+class VQAutoEncoder(nn.Module):
+    def __init__(self, img_size, nf, ch_mult, quantizer="nearest", res_blocks=2, attn_resolutions=[16], codebook_size=1024, emb_dim=256,
+                beta=0.25, gumbel_straight_through=False, gumbel_kl_weight=1e-8, model_path=None):
+        super().__init__()
+        logger = get_root_logger()
+        self.in_channels = 3 
+        self.nf = nf 
+        self.n_blocks = res_blocks 
+        self.codebook_size = codebook_size
+        self.embed_dim = emb_dim
+        self.ch_mult = ch_mult
+        self.resolution = img_size
+        self.attn_resolutions = attn_resolutions
+        self.quantizer_type = quantizer
+        self.encoder = Encoder(
+            self.in_channels,
+            self.nf,
+            self.embed_dim,
+            self.ch_mult,
+            self.n_blocks,
+            self.resolution,
+            self.attn_resolutions
+        )
+        if self.quantizer_type == "nearest":
+            self.beta = beta #0.25
+            self.quantize = VectorQuantizer(self.codebook_size, self.embed_dim, self.beta)
+        elif self.quantizer_type == "gumbel":
+            self.gumbel_num_hiddens = emb_dim
+            self.straight_through = gumbel_straight_through
+            self.kl_weight = gumbel_kl_weight
+            self.quantize = GumbelQuantizer(
+                self.codebook_size,
+                self.embed_dim,
+                self.gumbel_num_hiddens,
+                self.straight_through,
+                self.kl_weight
+            )
+        self.generator = Generator(
+            self.nf, 
+            self.embed_dim,
+            self.ch_mult, 
+            self.n_blocks, 
+            self.resolution, 
+            self.attn_resolutions
+        )
+
+        if model_path is not None:
+            chkpt = torch.load(model_path, map_location='cpu')
+            if 'params_ema' in chkpt:
+                self.load_state_dict(torch.load(model_path, map_location='cpu')['params_ema'])
+                logger.info(f'vqgan is loaded from: {model_path} [params_ema]')
+            elif 'params' in chkpt:
+                self.load_state_dict(torch.load(model_path, map_location='cpu')['params'])
+                logger.info(f'vqgan is loaded from: {model_path} [params]')
+            else:
+                raise ValueError(f'Wrong params!')
+
+
+    def forward(self, x):
+        x = self.encoder(x)
+        quant, codebook_loss, quant_stats = self.quantize(x)
+        x = self.generator(quant)
+        return x, codebook_loss, quant_stats
+
+
+
+# patch based discriminator
+@ARCH_REGISTRY.register()
+class VQGANDiscriminator(nn.Module):
+    def __init__(self, nc=3, ndf=64, n_layers=4, model_path=None):
+        super().__init__()
+
+        layers = [nn.Conv2d(nc, ndf, kernel_size=4, stride=2, padding=1), nn.LeakyReLU(0.2, True)]
+        ndf_mult = 1
+        ndf_mult_prev = 1
+        for n in range(1, n_layers):  # gradually increase the number of filters
+            ndf_mult_prev = ndf_mult
+            ndf_mult = min(2 ** n, 8)
+            layers += [
+                nn.Conv2d(ndf * ndf_mult_prev, ndf * ndf_mult, kernel_size=4, stride=2, padding=1, bias=False),
+                nn.BatchNorm2d(ndf * ndf_mult),
+                nn.LeakyReLU(0.2, True)
+            ]
+
+        ndf_mult_prev = ndf_mult
+        ndf_mult = min(2 ** n_layers, 8)
+
+        layers += [
+            nn.Conv2d(ndf * ndf_mult_prev, ndf * ndf_mult, kernel_size=4, stride=1, padding=1, bias=False),
+            nn.BatchNorm2d(ndf * ndf_mult),
+            nn.LeakyReLU(0.2, True)
+        ]
+
+        layers += [
+            nn.Conv2d(ndf * ndf_mult, 1, kernel_size=4, stride=1, padding=1)]  # output 1 channel prediction map
+        self.main = nn.Sequential(*layers)
+
+        if model_path is not None:
+            chkpt = torch.load(model_path, map_location='cpu')
+            if 'params_d' in chkpt:
+                self.load_state_dict(torch.load(model_path, map_location='cpu')['params_d'])
+            elif 'params' in chkpt:
+                self.load_state_dict(torch.load(model_path, map_location='cpu')['params'])
+            else:
+                raise ValueError(f'Wrong params!')
+
+    def forward(self, x):
+        return self.main(x)

basicsr/data/__init__.py

@@ -0,0 +1,100 @@
+import importlib
+import numpy as np
+import random
+import torch
+import torch.utils.data
+from copy import deepcopy
+from functools import partial
+from os import path as osp
+
+from basicsr.data.prefetch_dataloader import PrefetchDataLoader
+from basicsr.utils import get_root_logger, scandir
+from basicsr.utils.dist_util import get_dist_info
+from basicsr.utils.registry import DATASET_REGISTRY
+
+__all__ = ['build_dataset', 'build_dataloader']
+
+# automatically scan and import dataset modules for registry
+# scan all the files under the data folder with '_dataset' in file names
+data_folder = osp.dirname(osp.abspath(__file__))
+dataset_filenames = [osp.splitext(osp.basename(v))[0] for v in scandir(data_folder) if v.endswith('_dataset.py')]
+# import all the dataset modules
+_dataset_modules = [importlib.import_module(f'basicsr.data.{file_name}') for file_name in dataset_filenames]
+
+
+def build_dataset(dataset_opt):
+    """Build dataset from options.
+
+    Args:
+        dataset_opt (dict): Configuration for dataset. It must constain:
+            name (str): Dataset name.
+            type (str): Dataset type.
+    """
+    dataset_opt = deepcopy(dataset_opt)
+    dataset = DATASET_REGISTRY.get(dataset_opt['type'])(dataset_opt)
+    logger = get_root_logger()
+    logger.info(f'Dataset [{dataset.__class__.__name__}] - {dataset_opt["name"]} ' 'is built.')
+    return dataset
+
+
+def build_dataloader(dataset, dataset_opt, num_gpu=1, dist=False, sampler=None, seed=None):
+    """Build dataloader.
+
+    Args:
+        dataset (torch.utils.data.Dataset): Dataset.
+        dataset_opt (dict): Dataset options. It contains the following keys:
+            phase (str): 'train' or 'val'.
+            num_worker_per_gpu (int): Number of workers for each GPU.
+            batch_size_per_gpu (int): Training batch size for each GPU.
+        num_gpu (int): Number of GPUs. Used only in the train phase.
+            Default: 1.
+        dist (bool): Whether in distributed training. Used only in the train
+            phase. Default: False.
+        sampler (torch.utils.data.sampler): Data sampler. Default: None.
+        seed (int | None): Seed. Default: None
+    """
+    phase = dataset_opt['phase']
+    rank, _ = get_dist_info()
+    if phase == 'train':
+        if dist:  # distributed training
+            batch_size = dataset_opt['batch_size_per_gpu']
+            num_workers = dataset_opt['num_worker_per_gpu']
+        else:  # non-distributed training
+            multiplier = 1 if num_gpu == 0 else num_gpu
+            batch_size = dataset_opt['batch_size_per_gpu'] * multiplier
+            num_workers = dataset_opt['num_worker_per_gpu'] * multiplier
+        dataloader_args = dict(
+            dataset=dataset,
+            batch_size=batch_size,
+            shuffle=False,
+            num_workers=num_workers,
+            sampler=sampler,
+            drop_last=True)
+        if sampler is None:
+            dataloader_args['shuffle'] = True
+        dataloader_args['worker_init_fn'] = partial(
+            worker_init_fn, num_workers=num_workers, rank=rank, seed=seed) if seed is not None else None
+    elif phase in ['val', 'test']:  # validation
+        dataloader_args = dict(dataset=dataset, batch_size=1, shuffle=False, num_workers=0)
+    else:
+        raise ValueError(f'Wrong dataset phase: {phase}. ' "Supported ones are 'train', 'val' and 'test'.")
+
+    dataloader_args['pin_memory'] = dataset_opt.get('pin_memory', False)
+
+    prefetch_mode = dataset_opt.get('prefetch_mode')
+    if prefetch_mode == 'cpu':  # CPUPrefetcher
+        num_prefetch_queue = dataset_opt.get('num_prefetch_queue', 1)
+        logger = get_root_logger()
+        logger.info(f'Use {prefetch_mode} prefetch dataloader: ' f'num_prefetch_queue = {num_prefetch_queue}')
+        return PrefetchDataLoader(num_prefetch_queue=num_prefetch_queue, **dataloader_args)
+    else:
+        # prefetch_mode=None: Normal dataloader
+        # prefetch_mode='cuda': dataloader for CUDAPrefetcher
+        return torch.utils.data.DataLoader(**dataloader_args)
+
+
+def worker_init_fn(worker_id, num_workers, rank, seed):
+    # Set the worker seed to num_workers * rank + worker_id + seed
+    worker_seed = num_workers * rank + worker_id + seed
+    np.random.seed(worker_seed)
+    random.seed(worker_seed)

basicsr/data/data_sampler.py

@@ -0,0 +1,48 @@
+import math
+import torch
+from torch.utils.data.sampler import Sampler
+
+
+class EnlargedSampler(Sampler):
+    """Sampler that restricts data loading to a subset of the dataset.
+
+    Modified from torch.utils.data.distributed.DistributedSampler
+    Support enlarging the dataset for iteration-based training, for saving
+    time when restart the dataloader after each epoch
+
+    Args:
+        dataset (torch.utils.data.Dataset): Dataset used for sampling.
+        num_replicas (int | None): Number of processes participating in
+            the training. It is usually the world_size.
+        rank (int | None): Rank of the current process within num_replicas.
+        ratio (int): Enlarging ratio. Default: 1.
+    """
+
+    def __init__(self, dataset, num_replicas, rank, ratio=1):
+        self.dataset = dataset
+        self.num_replicas = num_replicas
+        self.rank = rank
+        self.epoch = 0
+        self.num_samples = math.ceil(len(self.dataset) * ratio / self.num_replicas)
+        self.total_size = self.num_samples * self.num_replicas
+
+    def __iter__(self):
+        # deterministically shuffle based on epoch
+        g = torch.Generator()
+        g.manual_seed(self.epoch)
+        indices = torch.randperm(self.total_size, generator=g).tolist()
+
+        dataset_size = len(self.dataset)
+        indices = [v % dataset_size for v in indices]
+
+        # subsample
+        indices = indices[self.rank:self.total_size:self.num_replicas]
+        assert len(indices) == self.num_samples
+
+        return iter(indices)
+
+    def __len__(self):
+        return self.num_samples
+
+    def set_epoch(self, epoch):
+        self.epoch = epoch

basicsr/data/data_util.py

@@ -0,0 +1,392 @@
+import cv2
+import math
+import numpy as np
+import torch
+from os import path as osp
+from PIL import Image, ImageDraw
+from torch.nn import functional as F
+
+from basicsr.data.transforms import mod_crop
+from basicsr.utils import img2tensor, scandir
+
+
+def read_img_seq(path, require_mod_crop=False, scale=1):
+    """Read a sequence of images from a given folder path.
+
+    Args:
+        path (list[str] | str): List of image paths or image folder path.
+        require_mod_crop (bool): Require mod crop for each image.
+            Default: False.
+        scale (int): Scale factor for mod_crop. Default: 1.
+
+    Returns:
+        Tensor: size (t, c, h, w), RGB, [0, 1].
+    """
+    if isinstance(path, list):
+        img_paths = path
+    else:
+        img_paths = sorted(list(scandir(path, full_path=True)))
+    imgs = [cv2.imread(v).astype(np.float32) / 255. for v in img_paths]
+    if require_mod_crop:
+        imgs = [mod_crop(img, scale) for img in imgs]
+    imgs = img2tensor(imgs, bgr2rgb=True, float32=True)
+    imgs = torch.stack(imgs, dim=0)
+    return imgs
+
+
+def generate_frame_indices(crt_idx, max_frame_num, num_frames, padding='reflection'):
+    """Generate an index list for reading `num_frames` frames from a sequence
+    of images.
+
+    Args:
+        crt_idx (int): Current center index.
+        max_frame_num (int): Max number of the sequence of images (from 1).
+        num_frames (int): Reading num_frames frames.
+        padding (str): Padding mode, one of
+            'replicate' | 'reflection' | 'reflection_circle' | 'circle'
+            Examples: current_idx = 0, num_frames = 5
+            The generated frame indices under different padding mode:
+            replicate: [0, 0, 0, 1, 2]
+            reflection: [2, 1, 0, 1, 2]
+            reflection_circle: [4, 3, 0, 1, 2]
+            circle: [3, 4, 0, 1, 2]
+
+    Returns:
+        list[int]: A list of indices.
+    """
+    assert num_frames % 2 == 1, 'num_frames should be an odd number.'
+    assert padding in ('replicate', 'reflection', 'reflection_circle', 'circle'), f'Wrong padding mode: {padding}.'
+
+    max_frame_num = max_frame_num - 1  # start from 0
+    num_pad = num_frames // 2
+
+    indices = []
+    for i in range(crt_idx - num_pad, crt_idx + num_pad + 1):
+        if i < 0:
+            if padding == 'replicate':
+                pad_idx = 0
+            elif padding == 'reflection':
+                pad_idx = -i
+            elif padding == 'reflection_circle':
+                pad_idx = crt_idx + num_pad - i
+            else:
+                pad_idx = num_frames + i
+        elif i > max_frame_num:
+            if padding == 'replicate':
+                pad_idx = max_frame_num
+            elif padding == 'reflection':
+                pad_idx = max_frame_num * 2 - i
+            elif padding == 'reflection_circle':
+                pad_idx = (crt_idx - num_pad) - (i - max_frame_num)
+            else:
+                pad_idx = i - num_frames
+        else:
+            pad_idx = i
+        indices.append(pad_idx)
+    return indices
+
+
+def paired_paths_from_lmdb(folders, keys):
+    """Generate paired paths from lmdb files.
+
+    Contents of lmdb. Taking the `lq.lmdb` for example, the file structure is:
+
+    lq.lmdb
+    ├── data.mdb
+    ├── lock.mdb
+    ├── meta_info.txt
+
+    The data.mdb and lock.mdb are standard lmdb files and you can refer to
+    https://lmdb.readthedocs.io/en/release/ for more details.
+
+    The meta_info.txt is a specified txt file to record the meta information
+    of our datasets. It will be automatically created when preparing
+    datasets by our provided dataset tools.
+    Each line in the txt file records
+    1)image name (with extension),
+    2)image shape,
+    3)compression level, separated by a white space.
+    Example: `baboon.png (120,125,3) 1`
+
+    We use the image name without extension as the lmdb key.
+    Note that we use the same key for the corresponding lq and gt images.
+
+    Args:
+        folders (list[str]): A list of folder path. The order of list should
+            be [input_folder, gt_folder].
+        keys (list[str]): A list of keys identifying folders. The order should
+            be in consistent with folders, e.g., ['lq', 'gt'].
+            Note that this key is different from lmdb keys.
+
+    Returns:
+        list[str]: Returned path list.
+    """
+    assert len(folders) == 2, ('The len of folders should be 2 with [input_folder, gt_folder]. '
+                               f'But got {len(folders)}')
+    assert len(keys) == 2, ('The len of keys should be 2 with [input_key, gt_key]. ' f'But got {len(keys)}')
+    input_folder, gt_folder = folders
+    input_key, gt_key = keys
+
+    if not (input_folder.endswith('.lmdb') and gt_folder.endswith('.lmdb')):
+        raise ValueError(f'{input_key} folder and {gt_key} folder should both in lmdb '
+                         f'formats. But received {input_key}: {input_folder}; '
+                         f'{gt_key}: {gt_folder}')
+    # ensure that the two meta_info files are the same
+    with open(osp.join(input_folder, 'meta_info.txt')) as fin:
+        input_lmdb_keys = [line.split('.')[0] for line in fin]
+    with open(osp.join(gt_folder, 'meta_info.txt')) as fin:
+        gt_lmdb_keys = [line.split('.')[0] for line in fin]
+    if set(input_lmdb_keys) != set(gt_lmdb_keys):
+        raise ValueError(f'Keys in {input_key}_folder and {gt_key}_folder are different.')
+    else:
+        paths = []
+        for lmdb_key in sorted(input_lmdb_keys):
+            paths.append(dict([(f'{input_key}_path', lmdb_key), (f'{gt_key}_path', lmdb_key)]))
+        return paths
+
+
+def paired_paths_from_meta_info_file(folders, keys, meta_info_file, filename_tmpl):
+    """Generate paired paths from an meta information file.
+
+    Each line in the meta information file contains the image names and
+    image shape (usually for gt), separated by a white space.
+
+    Example of an meta information file:
+    ```
+    0001_s001.png (480,480,3)
+    0001_s002.png (480,480,3)
+    ```
+
+    Args:
+        folders (list[str]): A list of folder path. The order of list should
+            be [input_folder, gt_folder].
+        keys (list[str]): A list of keys identifying folders. The order should
+            be in consistent with folders, e.g., ['lq', 'gt'].
+        meta_info_file (str): Path to the meta information file.
+        filename_tmpl (str): Template for each filename. Note that the
+            template excludes the file extension. Usually the filename_tmpl is
+            for files in the input folder.
+
+    Returns:
+        list[str]: Returned path list.
+    """
+    assert len(folders) == 2, ('The len of folders should be 2 with [input_folder, gt_folder]. '
+                               f'But got {len(folders)}')
+    assert len(keys) == 2, ('The len of keys should be 2 with [input_key, gt_key]. ' f'But got {len(keys)}')
+    input_folder, gt_folder = folders
+    input_key, gt_key = keys
+
+    with open(meta_info_file, 'r') as fin:
+        gt_names = [line.split(' ')[0] for line in fin]
+
+    paths = []
+    for gt_name in gt_names:
+        basename, ext = osp.splitext(osp.basename(gt_name))
+        input_name = f'{filename_tmpl.format(basename)}{ext}'
+        input_path = osp.join(input_folder, input_name)
+        gt_path = osp.join(gt_folder, gt_name)
+        paths.append(dict([(f'{input_key}_path', input_path), (f'{gt_key}_path', gt_path)]))
+    return paths
+
+
+def paired_paths_from_folder(folders, keys, filename_tmpl):
+    """Generate paired paths from folders.
+
+    Args:
+        folders (list[str]): A list of folder path. The order of list should
+            be [input_folder, gt_folder].
+        keys (list[str]): A list of keys identifying folders. The order should
+            be in consistent with folders, e.g., ['lq', 'gt'].
+        filename_tmpl (str): Template for each filename. Note that the
+            template excludes the file extension. Usually the filename_tmpl is
+            for files in the input folder.
+
+    Returns:
+        list[str]: Returned path list.
+    """
+    assert len(folders) == 2, ('The len of folders should be 2 with [input_folder, gt_folder]. '
+                               f'But got {len(folders)}')
+    assert len(keys) == 2, ('The len of keys should be 2 with [input_key, gt_key]. ' f'But got {len(keys)}')
+    input_folder, gt_folder = folders
+    input_key, gt_key = keys
+
+    input_paths = list(scandir(input_folder))
+    gt_paths = list(scandir(gt_folder))
+    assert len(input_paths) == len(gt_paths), (f'{input_key} and {gt_key} datasets have different number of images: '
+                                               f'{len(input_paths)}, {len(gt_paths)}.')
+    paths = []
+    for gt_path in gt_paths:
+        basename, ext = osp.splitext(osp.basename(gt_path))
+        input_name = f'{filename_tmpl.format(basename)}{ext}'
+        input_path = osp.join(input_folder, input_name)
+        assert input_name in input_paths, (f'{input_name} is not in ' f'{input_key}_paths.')
+        gt_path = osp.join(gt_folder, gt_path)
+        paths.append(dict([(f'{input_key}_path', input_path), (f'{gt_key}_path', gt_path)]))
+    return paths
+
+
+def paths_from_folder(folder):
+    """Generate paths from folder.
+
+    Args:
+        folder (str): Folder path.
+
+    Returns:
+        list[str]: Returned path list.
+    """
+
+    paths = list(scandir(folder))
+    paths = [osp.join(folder, path) for path in paths]
+    return paths
+
+
+def paths_from_lmdb(folder):
+    """Generate paths from lmdb.
+
+    Args:
+        folder (str): Folder path.
+
+    Returns:
+        list[str]: Returned path list.
+    """
+    if not folder.endswith('.lmdb'):
+        raise ValueError(f'Folder {folder}folder should in lmdb format.')
+    with open(osp.join(folder, 'meta_info.txt')) as fin:
+        paths = [line.split('.')[0] for line in fin]
+    return paths
+
+
+def generate_gaussian_kernel(kernel_size=13, sigma=1.6):
+    """Generate Gaussian kernel used in `duf_downsample`.
+
+    Args:
+        kernel_size (int): Kernel size. Default: 13.
+        sigma (float): Sigma of the Gaussian kernel. Default: 1.6.
+
+    Returns:
+        np.array: The Gaussian kernel.
+    """
+    from scipy.ndimage import filters as filters
+    kernel = np.zeros((kernel_size, kernel_size))
+    # set element at the middle to one, a dirac delta
+    kernel[kernel_size // 2, kernel_size // 2] = 1
+    # gaussian-smooth the dirac, resulting in a gaussian filter
+    return filters.gaussian_filter(kernel, sigma)
+
+
+def duf_downsample(x, kernel_size=13, scale=4):
+    """Downsamping with Gaussian kernel used in the DUF official code.
+
+    Args:
+        x (Tensor): Frames to be downsampled, with shape (b, t, c, h, w).
+        kernel_size (int): Kernel size. Default: 13.
+        scale (int): Downsampling factor. Supported scale: (2, 3, 4).
+            Default: 4.
+
+    Returns:
+        Tensor: DUF downsampled frames.
+    """
+    assert scale in (2, 3, 4), f'Only support scale (2, 3, 4), but got {scale}.'
+
+    squeeze_flag = False
+    if x.ndim == 4:
+        squeeze_flag = True
+        x = x.unsqueeze(0)
+    b, t, c, h, w = x.size()
+    x = x.view(-1, 1, h, w)
+    pad_w, pad_h = kernel_size // 2 + scale * 2, kernel_size // 2 + scale * 2
+    x = F.pad(x, (pad_w, pad_w, pad_h, pad_h), 'reflect')
+
+    gaussian_filter = generate_gaussian_kernel(kernel_size, 0.4 * scale)
+    gaussian_filter = torch.from_numpy(gaussian_filter).type_as(x).unsqueeze(0).unsqueeze(0)
+    x = F.conv2d(x, gaussian_filter, stride=scale)
+    x = x[:, :, 2:-2, 2:-2]
+    x = x.view(b, t, c, x.size(2), x.size(3))
+    if squeeze_flag:
+        x = x.squeeze(0)
+    return x
+
+
+def brush_stroke_mask(img, color=(255,255,255)):
+    min_num_vertex = 8
+    max_num_vertex = 28
+    mean_angle = 2*math.pi / 5
+    angle_range = 2*math.pi / 12
+    # training large mask ratio (training setting)
+    min_width = 30
+    max_width = 70
+    # very large mask ratio (test setting and refine after 200k)
+    # min_width = 80
+    # max_width = 120
+    def generate_mask(H, W, img=None):
+        average_radius = math.sqrt(H*H+W*W) / 8
+        mask = Image.new('RGB', (W, H), 0)
+        if img is not None: mask = img # Image.fromarray(img)
+
+        for _ in range(np.random.randint(1, 4)):
+            num_vertex = np.random.randint(min_num_vertex, max_num_vertex)
+            angle_min = mean_angle - np.random.uniform(0, angle_range)
+            angle_max = mean_angle + np.random.uniform(0, angle_range)
+            angles = []
+            vertex = []
+            for i in range(num_vertex):
+                if i % 2 == 0:
+                    angles.append(2*math.pi - np.random.uniform(angle_min, angle_max))
+                else:
+                    angles.append(np.random.uniform(angle_min, angle_max))
+
+            h, w = mask.size
+            vertex.append((int(np.random.randint(0, w)), int(np.random.randint(0, h))))
+            for i in range(num_vertex):
+                r = np.clip(
+                    np.random.normal(loc=average_radius, scale=average_radius//2),
+                    0, 2*average_radius)
+                new_x = np.clip(vertex[-1][0] + r * math.cos(angles[i]), 0, w)
+                new_y = np.clip(vertex[-1][1] + r * math.sin(angles[i]), 0, h)
+                vertex.append((int(new_x), int(new_y)))
+
+            draw = ImageDraw.Draw(mask)
+            width = int(np.random.uniform(min_width, max_width))
+            draw.line(vertex, fill=color, width=width)
+            for v in vertex:
+                draw.ellipse((v[0] - width//2,
+                              v[1] - width//2,
+                              v[0] + width//2,
+                              v[1] + width//2),
+                             fill=color)
+
+        return mask
+
+    width, height = img.size
+    mask = generate_mask(height, width, img)
+    return mask
+
+
+def random_ff_mask(shape, max_angle = 10, max_len = 100, max_width = 70, times = 10):
+    """Generate a random free form mask with configuration.
+    Args:
+        config: Config should have configuration including IMG_SHAPES,
+            VERTICAL_MARGIN, HEIGHT, HORIZONTAL_MARGIN, WIDTH.
+    Returns:
+        tuple: (top, left, height, width)
+    Link:
+        https://github.com/csqiangwen/DeepFillv2_Pytorch/blob/master/train_dataset.py
+    """
+    height = shape[0]
+    width = shape[1]
+    mask = np.zeros((height, width), np.float32)
+    times = np.random.randint(times-5, times)
+    for i in range(times):
+        start_x = np.random.randint(width)
+        start_y = np.random.randint(height)
+        for j in range(1 + np.random.randint(5)):
+            angle = 0.01 + np.random.randint(max_angle)
+            if i % 2 == 0:
+                angle = 2 * 3.1415926 - angle
+            length = 10 + np.random.randint(max_len-20, max_len)
+            brush_w = 5 + np.random.randint(max_width-30, max_width)
+            end_x = (start_x + length * np.sin(angle)).astype(np.int32)
+            end_y = (start_y + length * np.cos(angle)).astype(np.int32)
+            cv2.line(mask, (start_y, start_x), (end_y, end_x), 1.0, brush_w)
+            start_x, start_y = end_x, end_y
+    return mask.astype(np.float32)

basicsr/data/ffhq_blind_dataset.py

@@ -0,0 +1,299 @@
+import cv2
+import math
+import random
+import numpy as np
+import os.path as osp
+from scipy.io import loadmat
+from PIL import Image
+import torch
+import torch.utils.data as data
+from torchvision.transforms.functional import (adjust_brightness, adjust_contrast, 
+                                        adjust_hue, adjust_saturation, normalize)
+from basicsr.data import gaussian_kernels as gaussian_kernels
+from basicsr.data.transforms import augment
+from basicsr.data.data_util import paths_from_folder, brush_stroke_mask, random_ff_mask
+from basicsr.utils import FileClient, get_root_logger, imfrombytes, img2tensor
+from basicsr.utils.registry import DATASET_REGISTRY
+
+@DATASET_REGISTRY.register()
+class FFHQBlindDataset(data.Dataset):
+
+    def __init__(self, opt):
+        super(FFHQBlindDataset, self).__init__()
+        logger = get_root_logger()
+        self.opt = opt
+        # file client (io backend)
+        self.file_client = None
+        self.io_backend_opt = opt['io_backend']
+
+        self.gt_folder = opt['dataroot_gt']
+        self.gt_size = opt.get('gt_size', 512)
+        self.in_size = opt.get('in_size', 512)
+        assert self.gt_size >= self.in_size, 'Wrong setting.'
+        
+        self.mean = opt.get('mean', [0.5, 0.5, 0.5])
+        self.std = opt.get('std', [0.5, 0.5, 0.5])
+
+        self.component_path = opt.get('component_path', None)
+        self.latent_gt_path = opt.get('latent_gt_path', None)
+
+        if self.component_path is not None:
+            self.crop_components = True
+            self.components_dict = torch.load(self.component_path)
+            self.eye_enlarge_ratio = opt.get('eye_enlarge_ratio', 1.4)
+            self.nose_enlarge_ratio = opt.get('nose_enlarge_ratio', 1.1)
+            self.mouth_enlarge_ratio = opt.get('mouth_enlarge_ratio', 1.3)
+        else:
+            self.crop_components = False
+
+        if self.latent_gt_path is not None:
+            self.load_latent_gt = True            
+            self.latent_gt_dict = torch.load(self.latent_gt_path)
+        else:
+            self.load_latent_gt = False  
+
+        if self.io_backend_opt['type'] == 'lmdb':
+            self.io_backend_opt['db_paths'] = self.gt_folder
+            if not self.gt_folder.endswith('.lmdb'):
+                raise ValueError("'dataroot_gt' should end with '.lmdb', "f'but received {self.gt_folder}')
+            with open(osp.join(self.gt_folder, 'meta_info.txt')) as fin:
+                self.paths = [line.split('.')[0] for line in fin]
+        else:
+            self.paths = paths_from_folder(self.gt_folder)
+
+        # inpainting mask
+        self.gen_inpaint_mask = opt.get('gen_inpaint_mask', False)
+        if self.gen_inpaint_mask:
+            logger.info(f'generate mask ...')
+            # self.mask_max_angle = opt.get('mask_max_angle', 10)
+            # self.mask_max_len = opt.get('mask_max_len', 150)
+            # self.mask_max_width = opt.get('mask_max_width', 50)
+            # self.mask_draw_times = opt.get('mask_draw_times', 10)
+            # # print
+            # logger.info(f'mask_max_angle: {self.mask_max_angle}')
+            # logger.info(f'mask_max_len: {self.mask_max_len}')
+            # logger.info(f'mask_max_width: {self.mask_max_width}')
+            # logger.info(f'mask_draw_times: {self.mask_draw_times}')
+
+        # perform corrupt
+        self.use_corrupt = opt.get('use_corrupt', True)
+        self.use_motion_kernel = False
+        # self.use_motion_kernel = opt.get('use_motion_kernel', True)
+
+        if self.use_motion_kernel:
+            self.motion_kernel_prob = opt.get('motion_kernel_prob', 0.001)
+            motion_kernel_path = opt.get('motion_kernel_path', 'basicsr/data/motion-blur-kernels-32.pth')
+            self.motion_kernels = torch.load(motion_kernel_path)
+
+        if self.use_corrupt and not self.gen_inpaint_mask:
+            # degradation configurations
+            self.blur_kernel_size = opt['blur_kernel_size']
+            self.blur_sigma = opt['blur_sigma']
+            self.kernel_list = opt['kernel_list']
+            self.kernel_prob = opt['kernel_prob']
+            self.downsample_range = opt['downsample_range']
+            self.noise_range = opt['noise_range']
+            self.jpeg_range = opt['jpeg_range']
+            # print
+            logger.info(f'Blur: blur_kernel_size {self.blur_kernel_size}, sigma: [{", ".join(map(str, self.blur_sigma))}]')
+            logger.info(f'Downsample: downsample_range [{", ".join(map(str, self.downsample_range))}]')
+            logger.info(f'Noise: [{", ".join(map(str, self.noise_range))}]')
+            logger.info(f'JPEG compression: [{", ".join(map(str, self.jpeg_range))}]')
+
+        # color jitter
+        self.color_jitter_prob = opt.get('color_jitter_prob', None)
+        self.color_jitter_pt_prob = opt.get('color_jitter_pt_prob', None)
+        self.color_jitter_shift = opt.get('color_jitter_shift', 20)
+        if self.color_jitter_prob is not None:
+            logger.info(f'Use random color jitter. Prob: {self.color_jitter_prob}, shift: {self.color_jitter_shift}')
+
+        # to gray
+        self.gray_prob = opt.get('gray_prob', 0.0)
+        if self.gray_prob is not None:
+            logger.info(f'Use random gray. Prob: {self.gray_prob}')
+        self.color_jitter_shift /= 255.
+
+    @staticmethod
+    def color_jitter(img, shift):
+        """jitter color: randomly jitter the RGB values, in numpy formats"""
+        jitter_val = np.random.uniform(-shift, shift, 3).astype(np.float32)
+        img = img + jitter_val
+        img = np.clip(img, 0, 1)
+        return img
+
+    @staticmethod
+    def color_jitter_pt(img, brightness, contrast, saturation, hue):
+        """jitter color: randomly jitter the brightness, contrast, saturation, and hue, in torch Tensor formats"""
+        fn_idx = torch.randperm(4)
+        for fn_id in fn_idx:
+            if fn_id == 0 and brightness is not None:
+                brightness_factor = torch.tensor(1.0).uniform_(brightness[0], brightness[1]).item()
+                img = adjust_brightness(img, brightness_factor)
+
+            if fn_id == 1 and contrast is not None:
+                contrast_factor = torch.tensor(1.0).uniform_(contrast[0], contrast[1]).item()
+                img = adjust_contrast(img, contrast_factor)
+
+            if fn_id == 2 and saturation is not None:
+                saturation_factor = torch.tensor(1.0).uniform_(saturation[0], saturation[1]).item()
+                img = adjust_saturation(img, saturation_factor)
+
+            if fn_id == 3 and hue is not None:
+                hue_factor = torch.tensor(1.0).uniform_(hue[0], hue[1]).item()
+                img = adjust_hue(img, hue_factor)
+        return img
+
+
+    def get_component_locations(self, name, status):
+        components_bbox = self.components_dict[name]
+        if status[0]:  # hflip
+            # exchange right and left eye
+            tmp = components_bbox['left_eye']
+            components_bbox['left_eye'] = components_bbox['right_eye']
+            components_bbox['right_eye'] = tmp
+            # modify the width coordinate
+            components_bbox['left_eye'][0] = self.gt_size - components_bbox['left_eye'][0]
+            components_bbox['right_eye'][0] = self.gt_size - components_bbox['right_eye'][0]
+            components_bbox['nose'][0] = self.gt_size - components_bbox['nose'][0]
+            components_bbox['mouth'][0] = self.gt_size - components_bbox['mouth'][0]
+        
+        locations_gt = {}
+        locations_in = {}
+        for part in ['left_eye', 'right_eye', 'nose', 'mouth']:
+            mean = components_bbox[part][0:2]
+            half_len = components_bbox[part][2]
+            if 'eye' in part:
+                half_len *= self.eye_enlarge_ratio
+            elif part == 'nose':
+                half_len *= self.nose_enlarge_ratio
+            elif part == 'mouth':
+                half_len *= self.mouth_enlarge_ratio
+            loc = np.hstack((mean - half_len + 1, mean + half_len))
+            loc = torch.from_numpy(loc).float()
+            locations_gt[part] = loc
+            loc_in = loc/(self.gt_size//self.in_size)
+            locations_in[part] = loc_in
+        return locations_gt, locations_in
+
+
+    def __getitem__(self, index):
+        if self.file_client is None:
+            self.file_client = FileClient(self.io_backend_opt.pop('type'), **self.io_backend_opt)
+
+        # load gt image
+        gt_path = self.paths[index]
+        name = osp.basename(gt_path)[:-4]
+        img_bytes = self.file_client.get(gt_path)
+        img_gt = imfrombytes(img_bytes, float32=True)
+        
+        # random horizontal flip
+        img_gt, status = augment(img_gt, hflip=self.opt['use_hflip'], rotation=False, return_status=True)
+
+        if self.load_latent_gt:
+            if status[0]:
+                latent_gt = self.latent_gt_dict['hflip'][name]
+            else:
+                latent_gt = self.latent_gt_dict['orig'][name]
+
+        if self.crop_components:
+            locations_gt, locations_in = self.get_component_locations(name, status)
+
+        # generate in image
+        img_in = img_gt
+        if self.use_corrupt and not self.gen_inpaint_mask:
+            # motion blur
+            if self.use_motion_kernel and random.random() < self.motion_kernel_prob:
+                m_i = random.randint(0,31)
+                k = self.motion_kernels[f'{m_i:02d}']
+                img_in = cv2.filter2D(img_in,-1,k)
+            
+            # gaussian blur
+            kernel = gaussian_kernels.random_mixed_kernels(
+                self.kernel_list,
+                self.kernel_prob,
+                self.blur_kernel_size,
+                self.blur_sigma,
+                self.blur_sigma, 
+                [-math.pi, math.pi],
+                noise_range=None)
+            img_in = cv2.filter2D(img_in, -1, kernel)
+
+            # downsample
+            scale = np.random.uniform(self.downsample_range[0], self.downsample_range[1])
+            img_in = cv2.resize(img_in, (int(self.gt_size // scale), int(self.gt_size // scale)), interpolation=cv2.INTER_LINEAR)
+
+            # noise
+            if self.noise_range is not None:
+                noise_sigma = np.random.uniform(self.noise_range[0] / 255., self.noise_range[1] / 255.)
+                noise = np.float32(np.random.randn(*(img_in.shape))) * noise_sigma
+                img_in = img_in + noise
+                img_in = np.clip(img_in, 0, 1)
+
+            # jpeg
+            if self.jpeg_range is not None:
+                jpeg_p = np.random.uniform(self.jpeg_range[0], self.jpeg_range[1])
+                encode_param = [int(cv2.IMWRITE_JPEG_QUALITY), int(jpeg_p)]
+                _, encimg = cv2.imencode('.jpg', img_in * 255., encode_param)
+                img_in = np.float32(cv2.imdecode(encimg, 1)) / 255.
+
+            # resize to in_size
+            img_in = cv2.resize(img_in, (self.in_size, self.in_size), interpolation=cv2.INTER_LINEAR)
+
+        # if self.gen_inpaint_mask:
+        #     inpaint_mask = random_ff_mask(shape=(self.gt_size,self.gt_size), 
+        #         max_angle = self.mask_max_angle, max_len = self.mask_max_len, 
+        #         max_width = self.mask_max_width, times = self.mask_draw_times)
+        #     img_in = img_in * (1 - inpaint_mask.reshape(self.gt_size,self.gt_size,1)) + \
+        #              1.0 * inpaint_mask.reshape(self.gt_size,self.gt_size,1)
+
+        #     inpaint_mask = torch.from_numpy(inpaint_mask).view(1,self.gt_size,self.gt_size)
+
+        if self.gen_inpaint_mask:
+            img_in = (img_in*255).astype('uint8')
+            img_in = brush_stroke_mask(Image.fromarray(img_in))
+            img_in = np.array(img_in) / 255.
+
+        # random color jitter (only for lq)
+        if self.color_jitter_prob is not None and (np.random.uniform() < self.color_jitter_prob):
+            img_in = self.color_jitter(img_in, self.color_jitter_shift)
+        # random to gray (only for lq)
+        if self.gray_prob and np.random.uniform() < self.gray_prob:
+            img_in = cv2.cvtColor(img_in, cv2.COLOR_BGR2GRAY)
+            img_in = np.tile(img_in[:, :, None], [1, 1, 3])
+
+        # BGR to RGB, HWC to CHW, numpy to tensor
+        img_in, img_gt = img2tensor([img_in, img_gt], bgr2rgb=True, float32=True)
+
+        # random color jitter (pytorch version) (only for lq)
+        if self.color_jitter_pt_prob is not None and (np.random.uniform() < self.color_jitter_pt_prob):
+            brightness = self.opt.get('brightness', (0.5, 1.5))
+            contrast = self.opt.get('contrast', (0.5, 1.5))
+            saturation = self.opt.get('saturation', (0, 1.5))
+            hue = self.opt.get('hue', (-0.1, 0.1))
+            img_in = self.color_jitter_pt(img_in, brightness, contrast, saturation, hue)
+
+        # round and clip
+        img_in = np.clip((img_in * 255.0).round(), 0, 255) / 255.
+
+        # Set vgg range_norm=True if use the normalization here
+        # normalize
+        normalize(img_in, self.mean, self.std, inplace=True)
+        normalize(img_gt, self.mean, self.std, inplace=True)
+
+        return_dict = {'in': img_in, 'gt': img_gt, 'gt_path': gt_path}
+
+        if self.crop_components:
+            return_dict['locations_in'] = locations_in
+            return_dict['locations_gt'] = locations_gt
+
+        if self.load_latent_gt:
+            return_dict['latent_gt'] = latent_gt
+
+        # if self.gen_inpaint_mask:
+        #     return_dict['inpaint_mask'] = inpaint_mask
+
+        return return_dict
+
+
+    def __len__(self):
+        return len(self.paths)

basicsr/data/ffhq_blind_joint_dataset.py

@@ -0,0 +1,324 @@
+import cv2
+import math
+import random
+import numpy as np
+import os.path as osp
+from scipy.io import loadmat
+import torch
+import torch.utils.data as data
+from torchvision.transforms.functional import (adjust_brightness, adjust_contrast, 
+                                        adjust_hue, adjust_saturation, normalize)
+from basicsr.data import gaussian_kernels as gaussian_kernels
+from basicsr.data.transforms import augment
+from basicsr.data.data_util import paths_from_folder
+from basicsr.utils import FileClient, get_root_logger, imfrombytes, img2tensor
+from basicsr.utils.registry import DATASET_REGISTRY
+
+@DATASET_REGISTRY.register()
+class FFHQBlindJointDataset(data.Dataset):
+
+    def __init__(self, opt):
+        super(FFHQBlindJointDataset, self).__init__()
+        logger = get_root_logger()
+        self.opt = opt
+        # file client (io backend)
+        self.file_client = None
+        self.io_backend_opt = opt['io_backend']
+
+        self.gt_folder = opt['dataroot_gt']
+        self.gt_size = opt.get('gt_size', 512)
+        self.in_size = opt.get('in_size', 512)
+        assert self.gt_size >= self.in_size, 'Wrong setting.'
+        
+        self.mean = opt.get('mean', [0.5, 0.5, 0.5])
+        self.std = opt.get('std', [0.5, 0.5, 0.5])
+
+        self.component_path = opt.get('component_path', None)
+        self.latent_gt_path = opt.get('latent_gt_path', None)
+
+        if self.component_path is not None:
+            self.crop_components = True
+            self.components_dict = torch.load(self.component_path)
+            self.eye_enlarge_ratio = opt.get('eye_enlarge_ratio', 1.4)
+            self.nose_enlarge_ratio = opt.get('nose_enlarge_ratio', 1.1)
+            self.mouth_enlarge_ratio = opt.get('mouth_enlarge_ratio', 1.3)
+        else:
+            self.crop_components = False
+
+        if self.latent_gt_path is not None:
+            self.load_latent_gt = True            
+            self.latent_gt_dict = torch.load(self.latent_gt_path)
+        else:
+            self.load_latent_gt = False  
+
+        if self.io_backend_opt['type'] == 'lmdb':
+            self.io_backend_opt['db_paths'] = self.gt_folder
+            if not self.gt_folder.endswith('.lmdb'):
+                raise ValueError("'dataroot_gt' should end with '.lmdb', "f'but received {self.gt_folder}')
+            with open(osp.join(self.gt_folder, 'meta_info.txt')) as fin:
+                self.paths = [line.split('.')[0] for line in fin]
+        else:
+            self.paths = paths_from_folder(self.gt_folder)
+
+        # perform corrupt
+        self.use_corrupt = opt.get('use_corrupt', True)
+        self.use_motion_kernel = False
+        # self.use_motion_kernel = opt.get('use_motion_kernel', True)
+
+        if self.use_motion_kernel:
+            self.motion_kernel_prob = opt.get('motion_kernel_prob', 0.001)
+            motion_kernel_path = opt.get('motion_kernel_path', 'basicsr/data/motion-blur-kernels-32.pth')
+            self.motion_kernels = torch.load(motion_kernel_path)
+
+        if self.use_corrupt:
+            # degradation configurations
+            self.blur_kernel_size = self.opt['blur_kernel_size']
+            self.kernel_list = self.opt['kernel_list']
+            self.kernel_prob = self.opt['kernel_prob']
+            # Small degradation
+            self.blur_sigma = self.opt['blur_sigma']
+            self.downsample_range = self.opt['downsample_range']
+            self.noise_range = self.opt['noise_range']
+            self.jpeg_range = self.opt['jpeg_range']
+            # Large degradation
+            self.blur_sigma_large = self.opt['blur_sigma_large']
+            self.downsample_range_large = self.opt['downsample_range_large']
+            self.noise_range_large = self.opt['noise_range_large']
+            self.jpeg_range_large = self.opt['jpeg_range_large']
+
+            # print
+            logger.info(f'Blur: blur_kernel_size {self.blur_kernel_size}, sigma: [{", ".join(map(str, self.blur_sigma))}]')
+            logger.info(f'Downsample: downsample_range [{", ".join(map(str, self.downsample_range))}]')
+            logger.info(f'Noise: [{", ".join(map(str, self.noise_range))}]')
+            logger.info(f'JPEG compression: [{", ".join(map(str, self.jpeg_range))}]')
+
+        # color jitter
+        self.color_jitter_prob = opt.get('color_jitter_prob', None)
+        self.color_jitter_pt_prob = opt.get('color_jitter_pt_prob', None)
+        self.color_jitter_shift = opt.get('color_jitter_shift', 20)
+        if self.color_jitter_prob is not None:
+            logger.info(f'Use random color jitter. Prob: {self.color_jitter_prob}, shift: {self.color_jitter_shift}')
+
+        # to gray
+        self.gray_prob = opt.get('gray_prob', 0.0)
+        if self.gray_prob is not None:
+            logger.info(f'Use random gray. Prob: {self.gray_prob}')
+        self.color_jitter_shift /= 255.
+
+    @staticmethod
+    def color_jitter(img, shift):
+        """jitter color: randomly jitter the RGB values, in numpy formats"""
+        jitter_val = np.random.uniform(-shift, shift, 3).astype(np.float32)
+        img = img + jitter_val
+        img = np.clip(img, 0, 1)
+        return img
+
+    @staticmethod
+    def color_jitter_pt(img, brightness, contrast, saturation, hue):
+        """jitter color: randomly jitter the brightness, contrast, saturation, and hue, in torch Tensor formats"""
+        fn_idx = torch.randperm(4)
+        for fn_id in fn_idx:
+            if fn_id == 0 and brightness is not None:
+                brightness_factor = torch.tensor(1.0).uniform_(brightness[0], brightness[1]).item()
+                img = adjust_brightness(img, brightness_factor)
+
+            if fn_id == 1 and contrast is not None:
+                contrast_factor = torch.tensor(1.0).uniform_(contrast[0], contrast[1]).item()
+                img = adjust_contrast(img, contrast_factor)
+
+            if fn_id == 2 and saturation is not None:
+                saturation_factor = torch.tensor(1.0).uniform_(saturation[0], saturation[1]).item()
+                img = adjust_saturation(img, saturation_factor)
+
+            if fn_id == 3 and hue is not None:
+                hue_factor = torch.tensor(1.0).uniform_(hue[0], hue[1]).item()
+                img = adjust_hue(img, hue_factor)
+        return img
+
+
+    def get_component_locations(self, name, status):
+        components_bbox = self.components_dict[name]
+        if status[0]:  # hflip
+            # exchange right and left eye
+            tmp = components_bbox['left_eye']
+            components_bbox['left_eye'] = components_bbox['right_eye']
+            components_bbox['right_eye'] = tmp
+            # modify the width coordinate
+            components_bbox['left_eye'][0] = self.gt_size - components_bbox['left_eye'][0]
+            components_bbox['right_eye'][0] = self.gt_size - components_bbox['right_eye'][0]
+            components_bbox['nose'][0] = self.gt_size - components_bbox['nose'][0]
+            components_bbox['mouth'][0] = self.gt_size - components_bbox['mouth'][0]
+        
+        locations_gt = {}
+        locations_in = {}
+        for part in ['left_eye', 'right_eye', 'nose', 'mouth']:
+            mean = components_bbox[part][0:2]
+            half_len = components_bbox[part][2]
+            if 'eye' in part:
+                half_len *= self.eye_enlarge_ratio
+            elif part == 'nose':
+                half_len *= self.nose_enlarge_ratio
+            elif part == 'mouth':
+                half_len *= self.mouth_enlarge_ratio
+            loc = np.hstack((mean - half_len + 1, mean + half_len))
+            loc = torch.from_numpy(loc).float()
+            locations_gt[part] = loc
+            loc_in = loc/(self.gt_size//self.in_size)
+            locations_in[part] = loc_in
+        return locations_gt, locations_in
+
+
+    def __getitem__(self, index):
+        if self.file_client is None:
+            self.file_client = FileClient(self.io_backend_opt.pop('type'), **self.io_backend_opt)
+
+        # load gt image
+        gt_path = self.paths[index]
+        name = osp.basename(gt_path)[:-4]
+        img_bytes = self.file_client.get(gt_path)
+        img_gt = imfrombytes(img_bytes, float32=True)
+        
+        # random horizontal flip
+        img_gt, status = augment(img_gt, hflip=self.opt['use_hflip'], rotation=False, return_status=True)
+
+        if self.load_latent_gt:
+            if status[0]:
+                latent_gt = self.latent_gt_dict['hflip'][name]
+            else:
+                latent_gt = self.latent_gt_dict['orig'][name]
+
+        if self.crop_components:
+            locations_gt, locations_in = self.get_component_locations(name, status)
+
+        # generate in image
+        img_in = img_gt
+        if self.use_corrupt:
+            # motion blur
+            if self.use_motion_kernel and random.random() < self.motion_kernel_prob:
+                m_i = random.randint(0,31)
+                k = self.motion_kernels[f'{m_i:02d}']
+                img_in = cv2.filter2D(img_in,-1,k)
+            
+            # gaussian blur
+            kernel = gaussian_kernels.random_mixed_kernels(
+                self.kernel_list,
+                self.kernel_prob,
+                self.blur_kernel_size,
+                self.blur_sigma,
+                self.blur_sigma, 
+                [-math.pi, math.pi],
+                noise_range=None)
+            img_in = cv2.filter2D(img_in, -1, kernel)
+
+            # downsample
+            scale = np.random.uniform(self.downsample_range[0], self.downsample_range[1])
+            img_in = cv2.resize(img_in, (int(self.gt_size // scale), int(self.gt_size // scale)), interpolation=cv2.INTER_LINEAR)
+
+            # noise
+            if self.noise_range is not None:
+                noise_sigma = np.random.uniform(self.noise_range[0] / 255., self.noise_range[1] / 255.)
+                noise = np.float32(np.random.randn(*(img_in.shape))) * noise_sigma
+                img_in = img_in + noise
+                img_in = np.clip(img_in, 0, 1)
+
+            # jpeg
+            if self.jpeg_range is not None:
+                jpeg_p = np.random.uniform(self.jpeg_range[0], self.jpeg_range[1])
+                encode_param = [int(cv2.IMWRITE_JPEG_QUALITY), int(jpeg_p)]
+                _, encimg = cv2.imencode('.jpg', img_in * 255., encode_param)
+                img_in = np.float32(cv2.imdecode(encimg, 1)) / 255.
+
+            # resize to in_size
+            img_in = cv2.resize(img_in, (self.in_size, self.in_size), interpolation=cv2.INTER_LINEAR)
+
+
+        # generate in_large with large degradation
+        img_in_large = img_gt
+
+        if self.use_corrupt:
+            # motion blur
+            if self.use_motion_kernel and random.random() < self.motion_kernel_prob:
+                m_i = random.randint(0,31)
+                k = self.motion_kernels[f'{m_i:02d}']
+                img_in_large = cv2.filter2D(img_in_large,-1,k)
+            
+            # gaussian blur
+            kernel = gaussian_kernels.random_mixed_kernels(
+                self.kernel_list,
+                self.kernel_prob,
+                self.blur_kernel_size,
+                self.blur_sigma_large,
+                self.blur_sigma_large, 
+                [-math.pi, math.pi],
+                noise_range=None)
+            img_in_large = cv2.filter2D(img_in_large, -1, kernel)
+
+            # downsample
+            scale = np.random.uniform(self.downsample_range_large[0], self.downsample_range_large[1])
+            img_in_large = cv2.resize(img_in_large, (int(self.gt_size // scale), int(self.gt_size // scale)), interpolation=cv2.INTER_LINEAR)
+
+            # noise
+            if self.noise_range_large is not None:
+                noise_sigma = np.random.uniform(self.noise_range_large[0] / 255., self.noise_range_large[1] / 255.)
+                noise = np.float32(np.random.randn(*(img_in_large.shape))) * noise_sigma
+                img_in_large = img_in_large + noise
+                img_in_large = np.clip(img_in_large, 0, 1)
+
+            # jpeg
+            if self.jpeg_range_large is not None:
+                jpeg_p = np.random.uniform(self.jpeg_range_large[0], self.jpeg_range_large[1])
+                encode_param = [int(cv2.IMWRITE_JPEG_QUALITY), int(jpeg_p)]
+                _, encimg = cv2.imencode('.jpg', img_in_large * 255., encode_param)
+                img_in_large = np.float32(cv2.imdecode(encimg, 1)) / 255.
+
+            # resize to in_size
+            img_in_large = cv2.resize(img_in_large, (self.in_size, self.in_size), interpolation=cv2.INTER_LINEAR)
+
+
+        # random color jitter (only for lq)
+        if self.color_jitter_prob is not None and (np.random.uniform() < self.color_jitter_prob):
+            img_in = self.color_jitter(img_in, self.color_jitter_shift)
+            img_in_large = self.color_jitter(img_in_large, self.color_jitter_shift)
+        # random to gray (only for lq)
+        if self.gray_prob and np.random.uniform() < self.gray_prob:
+            img_in = cv2.cvtColor(img_in, cv2.COLOR_BGR2GRAY)
+            img_in = np.tile(img_in[:, :, None], [1, 1, 3])
+            img_in_large = cv2.cvtColor(img_in_large, cv2.COLOR_BGR2GRAY)
+            img_in_large = np.tile(img_in_large[:, :, None], [1, 1, 3])
+
+        # BGR to RGB, HWC to CHW, numpy to tensor
+        img_in, img_in_large, img_gt = img2tensor([img_in, img_in_large, img_gt], bgr2rgb=True, float32=True)
+
+        # random color jitter (pytorch version) (only for lq)
+        if self.color_jitter_pt_prob is not None and (np.random.uniform() < self.color_jitter_pt_prob):
+            brightness = self.opt.get('brightness', (0.5, 1.5))
+            contrast = self.opt.get('contrast', (0.5, 1.5))
+            saturation = self.opt.get('saturation', (0, 1.5))
+            hue = self.opt.get('hue', (-0.1, 0.1))
+            img_in = self.color_jitter_pt(img_in, brightness, contrast, saturation, hue)
+            img_in_large = self.color_jitter_pt(img_in_large, brightness, contrast, saturation, hue)
+
+        # round and clip
+        img_in = np.clip((img_in * 255.0).round(), 0, 255) / 255.
+        img_in_large = np.clip((img_in_large * 255.0).round(), 0, 255) / 255.
+
+        # Set vgg range_norm=True if use the normalization here
+        # normalize
+        normalize(img_in, self.mean, self.std, inplace=True)
+        normalize(img_in_large, self.mean, self.std, inplace=True)
+        normalize(img_gt, self.mean, self.std, inplace=True)
+
+        return_dict = {'in': img_in, 'in_large_de': img_in_large, 'gt': img_gt, 'gt_path': gt_path}
+
+        if self.crop_components:
+            return_dict['locations_in'] = locations_in
+            return_dict['locations_gt'] = locations_gt
+
+        if self.load_latent_gt:
+            return_dict['latent_gt'] = latent_gt
+
+        return return_dict
+
+
+    def __len__(self):
+        return len(self.paths)

basicsr/data/gaussian_kernels.py

@@ -0,0 +1,690 @@
+import math
+import numpy as np
+import random
+from scipy.ndimage.interpolation import shift
+from scipy.stats import multivariate_normal
+
+
+def sigma_matrix2(sig_x, sig_y, theta):
+    """Calculate the rotated sigma matrix (two dimensional matrix).
+    Args:
+        sig_x (float):
+        sig_y (float):
+        theta (float): Radian measurement.
+    Returns:
+        ndarray: Rotated sigma matrix.
+    """
+    D = np.array([[sig_x**2, 0], [0, sig_y**2]])
+    U = np.array([[np.cos(theta), -np.sin(theta)],
+                  [np.sin(theta), np.cos(theta)]])
+    return np.dot(U, np.dot(D, U.T))
+
+
+def mesh_grid(kernel_size):
+    """Generate the mesh grid, centering at zero.
+    Args:
+        kernel_size (int):
+    Returns:
+        xy (ndarray): with the shape (kernel_size, kernel_size, 2)
+        xx (ndarray): with the shape (kernel_size, kernel_size)
+        yy (ndarray): with the shape (kernel_size, kernel_size)
+    """
+    ax = np.arange(-kernel_size // 2 + 1., kernel_size // 2 + 1.)
+    xx, yy = np.meshgrid(ax, ax)
+    xy = np.hstack((xx.reshape((kernel_size * kernel_size, 1)),
+                    yy.reshape(kernel_size * kernel_size,
+                               1))).reshape(kernel_size, kernel_size, 2)
+    return xy, xx, yy
+
+
+def pdf2(sigma_matrix, grid):
+    """Calculate PDF of the bivariate Gaussian distribution.
+    Args:
+        sigma_matrix (ndarray): with the shape (2, 2)
+        grid (ndarray): generated by :func:`mesh_grid`,
+            with the shape (K, K, 2), K is the kernel size.
+    Returns:
+        kernel (ndarrray): un-normalized kernel.
+    """
+    inverse_sigma = np.linalg.inv(sigma_matrix)
+    kernel = np.exp(-0.5 * np.sum(np.dot(grid, inverse_sigma) * grid, 2))
+    return kernel
+
+
+def cdf2(D, grid):
+    """Calculate the CDF of the standard bivariate Gaussian distribution.
+        Used in skewed Gaussian distribution.
+    Args:
+        D (ndarrasy): skew matrix.
+        grid (ndarray): generated by :func:`mesh_grid`,
+            with the shape (K, K, 2), K is the kernel size.
+    Returns:
+        cdf (ndarray): skewed cdf.
+    """
+    rv = multivariate_normal([0, 0], [[1, 0], [0, 1]])
+    grid = np.dot(grid, D)
+    cdf = rv.cdf(grid)
+    return cdf
+
+
+def bivariate_skew_Gaussian(kernel_size, sig_x, sig_y, theta, D, grid=None):
+    """Generate a bivariate skew Gaussian kernel.
+        Described in `A multivariate skew normal distribution`_ by Shi et. al (2004).
+    Args:
+        kernel_size (int):
+        sig_x (float):
+        sig_y (float):
+        theta (float): Radian measurement.
+        D (ndarrasy): skew matrix.
+        grid (ndarray, optional): generated by :func:`mesh_grid`,
+            with the shape (K, K, 2), K is the kernel size. Default: None
+    Returns:
+        kernel (ndarray): normalized kernel.
+    .. _A multivariate skew normal distribution:
+        https://www.sciencedirect.com/science/article/pii/S0047259X03001313
+    """
+    if grid is None:
+        grid, _, _ = mesh_grid(kernel_size)
+    sigma_matrix = sigma_matrix2(sig_x, sig_y, theta)
+    pdf = pdf2(sigma_matrix, grid)
+    cdf = cdf2(D, grid)
+    kernel = pdf * cdf
+    kernel = kernel / np.sum(kernel)
+    return kernel
+
+
+def mass_center_shift(kernel_size, kernel):
+    """Calculate the shift of the mass center of a kenrel.
+    Args:
+        kernel_size (int):
+        kernel (ndarray): normalized kernel.
+    Returns:
+        delta_h (float):
+        delta_w (float):
+    """
+    ax = np.arange(-kernel_size // 2 + 1., kernel_size // 2 + 1.)
+    col_sum, row_sum = np.sum(kernel, axis=0), np.sum(kernel, axis=1)
+    delta_h = np.dot(row_sum, ax)
+    delta_w = np.dot(col_sum, ax)
+    return delta_h, delta_w
+
+
+def bivariate_skew_Gaussian_center(kernel_size,
+                                   sig_x,
+                                   sig_y,
+                                   theta,
+                                   D,
+                                   grid=None):
+    """Generate a bivariate skew Gaussian kernel at center. Shift with nearest padding.
+    Args:
+        kernel_size (int):
+        sig_x (float):
+        sig_y (float):
+        theta (float): Radian measurement.
+        D (ndarrasy): skew matrix.
+        grid (ndarray, optional): generated by :func:`mesh_grid`,
+            with the shape (K, K, 2), K is the kernel size. Default: None
+    Returns:
+        kernel (ndarray): centered and normalized kernel.
+    """
+    if grid is None:
+        grid, _, _ = mesh_grid(kernel_size)
+    kernel = bivariate_skew_Gaussian(kernel_size, sig_x, sig_y, theta, D, grid)
+    delta_h, delta_w = mass_center_shift(kernel_size, kernel)
+    kernel = shift(kernel, [-delta_h, -delta_w], mode='nearest')
+    kernel = kernel / np.sum(kernel)
+    return kernel
+
+
+def bivariate_anisotropic_Gaussian(kernel_size,
+                                   sig_x,
+                                   sig_y,
+                                   theta,
+                                   grid=None):
+    """Generate a bivariate anisotropic Gaussian kernel.
+    Args:
+        kernel_size (int):
+        sig_x (float):
+        sig_y (float):
+        theta (float): Radian measurement.
+        grid (ndarray, optional): generated by :func:`mesh_grid`,
+            with the shape (K, K, 2), K is the kernel size. Default: None
+    Returns:
+        kernel (ndarray): normalized kernel.
+    """
+    if grid is None:
+        grid, _, _ = mesh_grid(kernel_size)
+    sigma_matrix = sigma_matrix2(sig_x, sig_y, theta)
+    kernel = pdf2(sigma_matrix, grid)
+    kernel = kernel / np.sum(kernel)
+    return kernel
+
+
+def bivariate_isotropic_Gaussian(kernel_size, sig, grid=None):
+    """Generate a bivariate isotropic Gaussian kernel.
+    Args:
+        kernel_size (int):
+        sig (float):
+        grid (ndarray, optional): generated by :func:`mesh_grid`,
+            with the shape (K, K, 2), K is the kernel size. Default: None
+    Returns:
+        kernel (ndarray): normalized kernel.
+    """
+    if grid is None:
+        grid, _, _ = mesh_grid(kernel_size)
+    sigma_matrix = np.array([[sig**2, 0], [0, sig**2]])
+    kernel = pdf2(sigma_matrix, grid)
+    kernel = kernel / np.sum(kernel)
+    return kernel
+
+
+def bivariate_generalized_Gaussian(kernel_size,
+                                   sig_x,
+                                   sig_y,
+                                   theta,
+                                   beta,
+                                   grid=None):
+    """Generate a bivariate generalized Gaussian kernel.
+        Described in `Parameter Estimation For Multivariate Generalized Gaussian Distributions`_
+        by Pascal et. al (2013).
+    Args:
+        kernel_size (int):
+        sig_x (float):
+        sig_y (float):
+        theta (float): Radian measurement.
+        beta (float): shape parameter, beta = 1 is the normal distribution.
+        grid (ndarray, optional): generated by :func:`mesh_grid`,
+            with the shape (K, K, 2), K is the kernel size. Default: None
+    Returns:
+        kernel (ndarray): normalized kernel.
+    .. _Parameter Estimation For Multivariate Generalized Gaussian Distributions:
+        https://arxiv.org/abs/1302.6498
+    """
+    if grid is None:
+        grid, _, _ = mesh_grid(kernel_size)
+    sigma_matrix = sigma_matrix2(sig_x, sig_y, theta)
+    inverse_sigma = np.linalg.inv(sigma_matrix)
+    kernel = np.exp(
+        -0.5 * np.power(np.sum(np.dot(grid, inverse_sigma) * grid, 2), beta))
+    kernel = kernel / np.sum(kernel)
+    return kernel
+
+
+def bivariate_plateau_type1(kernel_size, sig_x, sig_y, theta, beta, grid=None):
+    """Generate a plateau-like anisotropic kernel.
+    1 / (1+x^(beta))
+    Args:
+        kernel_size (int):
+        sig_x (float):
+        sig_y (float):
+        theta (float): Radian measurement.
+        beta (float): shape parameter, beta = 1 is the normal distribution.
+        grid (ndarray, optional): generated by :func:`mesh_grid`,
+            with the shape (K, K, 2), K is the kernel size. Default: None
+    Returns:
+        kernel (ndarray): normalized kernel.
+    """
+    if grid is None:
+        grid, _, _ = mesh_grid(kernel_size)
+    sigma_matrix = sigma_matrix2(sig_x, sig_y, theta)
+    inverse_sigma = np.linalg.inv(sigma_matrix)
+    kernel = np.reciprocal(
+        np.power(np.sum(np.dot(grid, inverse_sigma) * grid, 2), beta) + 1)
+    kernel = kernel / np.sum(kernel)
+    return kernel
+
+
+def bivariate_plateau_type1_iso(kernel_size, sig, beta, grid=None):
+    """Generate a plateau-like isotropic kernel.
+    1 / (1+x^(beta))
+    Args:
+        kernel_size (int):
+        sig (float):
+        beta (float): shape parameter, beta = 1 is the normal distribution.
+        grid (ndarray, optional): generated by :func:`mesh_grid`,
+            with the shape (K, K, 2), K is the kernel size. Default: None
+    Returns:
+        kernel (ndarray): normalized kernel.
+    """
+    if grid is None:
+        grid, _, _ = mesh_grid(kernel_size)
+    sigma_matrix = np.array([[sig**2, 0], [0, sig**2]])
+    inverse_sigma = np.linalg.inv(sigma_matrix)
+    kernel = np.reciprocal(
+        np.power(np.sum(np.dot(grid, inverse_sigma) * grid, 2), beta) + 1)
+    kernel = kernel / np.sum(kernel)
+    return kernel
+
+
+def random_bivariate_skew_Gaussian_center(kernel_size,
+                                          sigma_x_range,
+                                          sigma_y_range,
+                                          rotation_range,
+                                          noise_range=None,
+                                          strict=False):
+    """Randomly generate bivariate skew Gaussian kernels at center.
+    Args:
+        kernel_size (int):
+        sigma_x_range (tuple): [0.6, 5]
+        sigma_y_range (tuple): [0.6, 5]
+        rotation range (tuple): [-math.pi, math.pi]
+        noise_range(tuple, optional): multiplicative kernel noise, [0.75, 1.25]. Default: None
+    Returns:
+        kernel (ndarray):
+    """
+    assert kernel_size % 2 == 1, 'Kernel size must be an odd number.'
+    assert sigma_x_range[0] < sigma_x_range[1], 'Wrong sigma_x_range.'
+    assert sigma_y_range[0] < sigma_y_range[1], 'Wrong sigma_y_range.'
+    assert rotation_range[0] < rotation_range[1], 'Wrong rotation_range.'
+    sigma_x = np.random.uniform(sigma_x_range[0], sigma_x_range[1])
+    sigma_y = np.random.uniform(sigma_y_range[0], sigma_y_range[1])
+    if strict:
+        sigma_max = np.max([sigma_x, sigma_y])
+        sigma_min = np.min([sigma_x, sigma_y])
+        sigma_x, sigma_y = sigma_max, sigma_min
+    rotation = np.random.uniform(rotation_range[0], rotation_range[1])
+
+    sigma_max = np.max([sigma_x, sigma_y])
+    thres = 3 / sigma_max
+    D = [[np.random.uniform(-thres, thres),
+          np.random.uniform(-thres, thres)],
+         [np.random.uniform(-thres, thres),
+          np.random.uniform(-thres, thres)]]
+
+    kernel = bivariate_skew_Gaussian_center(kernel_size, sigma_x, sigma_y,
+                                            rotation, D)
+
+    # add multiplicative noise
+    if noise_range is not None:
+        assert noise_range[0] < noise_range[1], 'Wrong noise range.'
+        noise = np.random.uniform(
+            noise_range[0], noise_range[1], size=kernel.shape)
+        kernel = kernel * noise
+    kernel = kernel / np.sum(kernel)
+    if strict:
+        return kernel, sigma_x, sigma_y, rotation, D
+    else:
+        return kernel
+
+
+def random_bivariate_anisotropic_Gaussian(kernel_size,
+                                          sigma_x_range,
+                                          sigma_y_range,
+                                          rotation_range,
+                                          noise_range=None,
+                                          strict=False):
+    """Randomly generate bivariate anisotropic Gaussian kernels.
+    Args:
+        kernel_size (int):
+        sigma_x_range (tuple): [0.6, 5]
+        sigma_y_range (tuple): [0.6, 5]
+        rotation range (tuple): [-math.pi, math.pi]
+        noise_range(tuple, optional): multiplicative kernel noise, [0.75, 1.25]. Default: None
+    Returns:
+        kernel (ndarray):
+    """
+    assert kernel_size % 2 == 1, 'Kernel size must be an odd number.'
+    assert sigma_x_range[0] < sigma_x_range[1], 'Wrong sigma_x_range.'
+    assert sigma_y_range[0] < sigma_y_range[1], 'Wrong sigma_y_range.'
+    assert rotation_range[0] < rotation_range[1], 'Wrong rotation_range.'
+    sigma_x = np.random.uniform(sigma_x_range[0], sigma_x_range[1])
+    sigma_y = np.random.uniform(sigma_y_range[0], sigma_y_range[1])
+    if strict:
+        sigma_max = np.max([sigma_x, sigma_y])
+        sigma_min = np.min([sigma_x, sigma_y])
+        sigma_x, sigma_y = sigma_max, sigma_min
+    rotation = np.random.uniform(rotation_range[0], rotation_range[1])
+
+    kernel = bivariate_anisotropic_Gaussian(kernel_size, sigma_x, sigma_y,
+                                            rotation)
+
+    # add multiplicative noise
+    if noise_range is not None:
+        assert noise_range[0] < noise_range[1], 'Wrong noise range.'
+        noise = np.random.uniform(
+            noise_range[0], noise_range[1], size=kernel.shape)
+        kernel = kernel * noise
+    kernel = kernel / np.sum(kernel)
+    if strict:
+        return kernel, sigma_x, sigma_y, rotation
+    else:
+        return kernel
+
+
+def random_bivariate_isotropic_Gaussian(kernel_size,
+                                        sigma_range,
+                                        noise_range=None,
+                                        strict=False):
+    """Randomly generate bivariate isotropic Gaussian kernels.
+    Args:
+        kernel_size (int):
+        sigma_range (tuple): [0.6, 5]
+        noise_range(tuple, optional): multiplicative kernel noise, [0.75, 1.25]. Default: None
+    Returns:
+        kernel (ndarray):
+    """
+    assert kernel_size % 2 == 1, 'Kernel size must be an odd number.'
+    assert sigma_range[0] < sigma_range[1], 'Wrong sigma_x_range.'
+    sigma = np.random.uniform(sigma_range[0], sigma_range[1])
+
+    kernel = bivariate_isotropic_Gaussian(kernel_size, sigma)
+
+    # add multiplicative noise
+    if noise_range is not None:
+        assert noise_range[0] < noise_range[1], 'Wrong noise range.'
+        noise = np.random.uniform(
+            noise_range[0], noise_range[1], size=kernel.shape)
+        kernel = kernel * noise
+    kernel = kernel / np.sum(kernel)
+    if strict:
+        return kernel, sigma
+    else:
+        return kernel
+
+
+def random_bivariate_generalized_Gaussian(kernel_size,
+                                          sigma_x_range,
+                                          sigma_y_range,
+                                          rotation_range,
+                                          beta_range,
+                                          noise_range=None,
+                                          strict=False):
+    """Randomly generate bivariate generalized Gaussian kernels.
+    Args:
+        kernel_size (int):
+        sigma_x_range (tuple): [0.6, 5]
+        sigma_y_range (tuple): [0.6, 5]
+        rotation range (tuple): [-math.pi, math.pi]
+        beta_range (tuple): [0.5, 8]
+        noise_range(tuple, optional): multiplicative kernel noise, [0.75, 1.25]. Default: None
+    Returns:
+        kernel (ndarray):
+    """
+    assert kernel_size % 2 == 1, 'Kernel size must be an odd number.'
+    assert sigma_x_range[0] < sigma_x_range[1], 'Wrong sigma_x_range.'
+    assert sigma_y_range[0] < sigma_y_range[1], 'Wrong sigma_y_range.'
+    assert rotation_range[0] < rotation_range[1], 'Wrong rotation_range.'
+    sigma_x = np.random.uniform(sigma_x_range[0], sigma_x_range[1])
+    sigma_y = np.random.uniform(sigma_y_range[0], sigma_y_range[1])
+    if strict:
+        sigma_max = np.max([sigma_x, sigma_y])
+        sigma_min = np.min([sigma_x, sigma_y])
+        sigma_x, sigma_y = sigma_max, sigma_min
+    rotation = np.random.uniform(rotation_range[0], rotation_range[1])
+    if np.random.uniform() < 0.5:
+        beta = np.random.uniform(beta_range[0], 1)
+    else:
+        beta = np.random.uniform(1, beta_range[1])
+
+    kernel = bivariate_generalized_Gaussian(kernel_size, sigma_x, sigma_y,
+                                            rotation, beta)
+
+    # add multiplicative noise
+    if noise_range is not None:
+        assert noise_range[0] < noise_range[1], 'Wrong noise range.'
+        noise = np.random.uniform(
+            noise_range[0], noise_range[1], size=kernel.shape)
+        kernel = kernel * noise
+    kernel = kernel / np.sum(kernel)
+    if strict:
+        return kernel, sigma_x, sigma_y, rotation, beta
+    else:
+        return kernel
+
+
+def random_bivariate_plateau_type1(kernel_size,
+                                   sigma_x_range,
+                                   sigma_y_range,
+                                   rotation_range,
+                                   beta_range,
+                                   noise_range=None,
+                                   strict=False):
+    """Randomly generate bivariate plateau type1 kernels.
+    Args:
+        kernel_size (int):
+        sigma_x_range (tuple): [0.6, 5]
+        sigma_y_range (tuple): [0.6, 5]
+        rotation range (tuple): [-math.pi/2, math.pi/2]
+        beta_range (tuple): [1, 4]
+        noise_range(tuple, optional): multiplicative kernel noise, [0.75, 1.25]. Default: None
+    Returns:
+        kernel (ndarray):
+    """
+    assert kernel_size % 2 == 1, 'Kernel size must be an odd number.'
+    assert sigma_x_range[0] < sigma_x_range[1], 'Wrong sigma_x_range.'
+    assert sigma_y_range[0] < sigma_y_range[1], 'Wrong sigma_y_range.'
+    assert rotation_range[0] < rotation_range[1], 'Wrong rotation_range.'
+    sigma_x = np.random.uniform(sigma_x_range[0], sigma_x_range[1])
+    sigma_y = np.random.uniform(sigma_y_range[0], sigma_y_range[1])
+    if strict:
+        sigma_max = np.max([sigma_x, sigma_y])
+        sigma_min = np.min([sigma_x, sigma_y])
+        sigma_x, sigma_y = sigma_max, sigma_min
+    rotation = np.random.uniform(rotation_range[0], rotation_range[1])
+    if np.random.uniform() < 0.5:
+        beta = np.random.uniform(beta_range[0], 1)
+    else:
+        beta = np.random.uniform(1, beta_range[1])
+
+    kernel = bivariate_plateau_type1(kernel_size, sigma_x, sigma_y, rotation,
+                                     beta)
+
+    # add multiplicative noise
+    if noise_range is not None:
+        assert noise_range[0] < noise_range[1], 'Wrong noise range.'
+        noise = np.random.uniform(
+            noise_range[0], noise_range[1], size=kernel.shape)
+        kernel = kernel * noise
+    kernel = kernel / np.sum(kernel)
+    if strict:
+        return kernel, sigma_x, sigma_y, rotation, beta
+    else:
+        return kernel
+
+
+def random_bivariate_plateau_type1_iso(kernel_size,
+                                       sigma_range,
+                                       beta_range,
+                                       noise_range=None,
+                                       strict=False):
+    """Randomly generate bivariate plateau type1 kernels (iso).
+    Args:
+        kernel_size (int):
+        sigma_range (tuple): [0.6, 5]
+        beta_range (tuple): [1, 4]
+        noise_range(tuple, optional): multiplicative kernel noise, [0.75, 1.25]. Default: None
+    Returns:
+        kernel (ndarray):
+    """
+    assert kernel_size % 2 == 1, 'Kernel size must be an odd number.'
+    assert sigma_range[0] < sigma_range[1], 'Wrong sigma_x_range.'
+    sigma = np.random.uniform(sigma_range[0], sigma_range[1])
+    beta = np.random.uniform(beta_range[0], beta_range[1])
+
+    kernel = bivariate_plateau_type1_iso(kernel_size, sigma, beta)
+
+    # add multiplicative noise
+    if noise_range is not None:
+        assert noise_range[0] < noise_range[1], 'Wrong noise range.'
+        noise = np.random.uniform(
+            noise_range[0], noise_range[1], size=kernel.shape)
+        kernel = kernel * noise
+    kernel = kernel / np.sum(kernel)
+    if strict:
+        return kernel, sigma, beta
+    else:
+        return kernel
+
+
+def random_mixed_kernels(kernel_list,
+                         kernel_prob,
+                         kernel_size=21,
+                         sigma_x_range=[0.6, 5],
+                         sigma_y_range=[0.6, 5],
+                         rotation_range=[-math.pi, math.pi],
+                         beta_range=[0.5, 8],
+                         noise_range=None):
+    """Randomly generate mixed kernels.
+    Args:
+        kernel_list (tuple): a list name of kenrel types,
+            support ['iso', 'aniso', 'skew', 'generalized', 'plateau_iso', 'plateau_aniso']
+        kernel_prob (tuple): corresponding kernel probability for each kernel type
+        kernel_size (int):
+        sigma_x_range (tuple): [0.6, 5]
+        sigma_y_range (tuple): [0.6, 5]
+        rotation range (tuple): [-math.pi, math.pi]
+        beta_range (tuple): [0.5, 8]
+        noise_range(tuple, optional): multiplicative kernel noise, [0.75, 1.25]. Default: None
+    Returns:
+        kernel (ndarray):
+    """
+    kernel_type = random.choices(kernel_list, kernel_prob)[0]
+    if kernel_type == 'iso':
+        kernel = random_bivariate_isotropic_Gaussian(
+            kernel_size, sigma_x_range, noise_range=noise_range)
+    elif kernel_type == 'aniso':
+        kernel = random_bivariate_anisotropic_Gaussian(
+            kernel_size,
+            sigma_x_range,
+            sigma_y_range,
+            rotation_range,
+            noise_range=noise_range)
+    elif kernel_type == 'skew':
+        kernel = random_bivariate_skew_Gaussian_center(
+            kernel_size,
+            sigma_x_range,
+            sigma_y_range,
+            rotation_range,
+            noise_range=noise_range)
+    elif kernel_type == 'generalized':
+        kernel = random_bivariate_generalized_Gaussian(
+            kernel_size,
+            sigma_x_range,
+            sigma_y_range,
+            rotation_range,
+            beta_range,
+            noise_range=noise_range)
+    elif kernel_type == 'plateau_iso':
+        kernel = random_bivariate_plateau_type1_iso(
+            kernel_size, sigma_x_range, beta_range, noise_range=noise_range)
+    elif kernel_type == 'plateau_aniso':
+        kernel = random_bivariate_plateau_type1(
+            kernel_size,
+            sigma_x_range,
+            sigma_y_range,
+            rotation_range,
+            beta_range,
+            noise_range=noise_range)
+    # add multiplicative noise
+    if noise_range is not None:
+        assert noise_range[0] < noise_range[1], 'Wrong noise range.'
+        noise = np.random.uniform(
+            noise_range[0], noise_range[1], size=kernel.shape)
+        kernel = kernel * noise
+    kernel = kernel / np.sum(kernel)
+    return kernel
+
+
+def show_one_kernel():
+    import matplotlib.pyplot as plt
+    kernel_size = 21
+
+    # bivariate skew Gaussian
+    D = [[0, 0], [0, 0]]
+    D = [[3 / 4, 0], [0, 0.5]]
+    kernel = bivariate_skew_Gaussian_center(kernel_size, 2, 4, -math.pi / 4, D)
+    # bivariate anisotropic Gaussian
+    kernel = bivariate_anisotropic_Gaussian(kernel_size, 2, 4, -math.pi / 4)
+    # bivariate anisotropic Gaussian
+    kernel = bivariate_isotropic_Gaussian(kernel_size, 1)
+    # bivariate generalized Gaussian
+    kernel = bivariate_generalized_Gaussian(
+        kernel_size, 2, 4, -math.pi / 4, beta=4)
+
+    delta_h, delta_w = mass_center_shift(kernel_size, kernel)
+    print(delta_h, delta_w)
+
+    fig, axs = plt.subplots(nrows=2, ncols=2)
+    # axs.set_axis_off()
+    ax = axs[0][0]
+    im = ax.matshow(kernel, cmap='jet', origin='upper')
+    fig.colorbar(im, ax=ax)
+
+    # image
+    ax = axs[0][1]
+    kernel_vis = kernel - np.min(kernel)
+    kernel_vis = kernel_vis / np.max(kernel_vis) * 255.
+    ax.imshow(kernel_vis, interpolation='nearest')
+
+    _, xx, yy = mesh_grid(kernel_size)
+    # contour
+    ax = axs[1][0]
+    CS = ax.contour(xx, yy, kernel, origin='upper')
+    ax.clabel(CS, inline=1, fontsize=3)
+
+    # contourf
+    ax = axs[1][1]
+    kernel = kernel / np.max(kernel)
+    p = ax.contourf(
+        xx, yy, kernel, origin='upper', levels=np.linspace(-0.05, 1.05, 10))
+    fig.colorbar(p)
+
+    plt.show()
+
+
+def show_plateau_kernel():
+    import matplotlib.pyplot as plt
+    kernel_size = 21
+
+    kernel = plateau_type1(kernel_size, 2, 4, -math.pi / 8, 2, grid=None)
+    kernel_norm = bivariate_isotropic_Gaussian(kernel_size, 5)
+    kernel_gau = bivariate_generalized_Gaussian(
+        kernel_size, 2, 4, -math.pi / 8, 2, grid=None)
+    delta_h, delta_w = mass_center_shift(kernel_size, kernel)
+    print(delta_h, delta_w)
+
+    # kernel_slice = kernel[10, :]
+    # kernel_gau_slice = kernel_gau[10, :]
+    # kernel_norm_slice = kernel_norm[10, :]
+    # fig, ax = plt.subplots()
+    # t = list(range(1, 22))
+
+    # ax.plot(t, kernel_gau_slice)
+    # ax.plot(t, kernel_slice)
+    # ax.plot(t, kernel_norm_slice)
+
+    # t = np.arange(0, 10, 0.1)
+    # y = np.exp(-0.5 * t)
+    # y2 = np.reciprocal(1 + t)
+    # print(t.shape)
+    # print(y.shape)
+    # ax.plot(t, y)
+    # ax.plot(t, y2)
+    # plt.show()
+
+    fig, axs = plt.subplots(nrows=2, ncols=2)
+    # axs.set_axis_off()
+    ax = axs[0][0]
+    im = ax.matshow(kernel, cmap='jet', origin='upper')
+    fig.colorbar(im, ax=ax)
+
+    # image
+    ax = axs[0][1]
+    kernel_vis = kernel - np.min(kernel)
+    kernel_vis = kernel_vis / np.max(kernel_vis) * 255.
+    ax.imshow(kernel_vis, interpolation='nearest')
+
+    _, xx, yy = mesh_grid(kernel_size)
+    # contour
+    ax = axs[1][0]
+    CS = ax.contour(xx, yy, kernel, origin='upper')
+    ax.clabel(CS, inline=1, fontsize=3)
+
+    # contourf
+    ax = axs[1][1]
+    kernel = kernel / np.max(kernel)
+    p = ax.contourf(
+        xx, yy, kernel, origin='upper', levels=np.linspace(-0.05, 1.05, 10))
+    fig.colorbar(p)
+
+    plt.show()

basicsr/data/paired_image_dataset.py

@@ -0,0 +1,101 @@
+from torch.utils import data as data
+from torchvision.transforms.functional import normalize
+
+from basicsr.data.data_util import paired_paths_from_folder, paired_paths_from_lmdb, paired_paths_from_meta_info_file
+from basicsr.data.transforms import augment, paired_random_crop
+from basicsr.utils import FileClient, imfrombytes, img2tensor
+from basicsr.utils.registry import DATASET_REGISTRY
+
+
+@DATASET_REGISTRY.register()
+class PairedImageDataset(data.Dataset):
+    """Paired image dataset for image restoration.
+
+    Read LQ (Low Quality, e.g. LR (Low Resolution), blurry, noisy, etc) and
+    GT image pairs.
+
+    There are three modes:
+    1. 'lmdb': Use lmdb files.
+        If opt['io_backend'] == lmdb.
+    2. 'meta_info_file': Use meta information file to generate paths.
+        If opt['io_backend'] != lmdb and opt['meta_info_file'] is not None.
+    3. 'folder': Scan folders to generate paths.
+        The rest.
+
+    Args:
+        opt (dict): Config for train datasets. It contains the following keys:
+            dataroot_gt (str): Data root path for gt.
+            dataroot_lq (str): Data root path for lq.
+            meta_info_file (str): Path for meta information file.
+            io_backend (dict): IO backend type and other kwarg.
+            filename_tmpl (str): Template for each filename. Note that the
+                template excludes the file extension. Default: '{}'.
+            gt_size (int): Cropped patched size for gt patches.
+            use_flip (bool): Use horizontal flips.
+            use_rot (bool): Use rotation (use vertical flip and transposing h
+                and w for implementation).
+
+            scale (bool): Scale, which will be added automatically.
+            phase (str): 'train' or 'val'.
+    """
+
+    def __init__(self, opt):
+        super(PairedImageDataset, self).__init__()
+        self.opt = opt
+        # file client (io backend)
+        self.file_client = None
+        self.io_backend_opt = opt['io_backend']
+        self.mean = opt['mean'] if 'mean' in opt else None
+        self.std = opt['std'] if 'std' in opt else None
+
+        self.gt_folder, self.lq_folder = opt['dataroot_gt'], opt['dataroot_lq']
+        if 'filename_tmpl' in opt:
+            self.filename_tmpl = opt['filename_tmpl']
+        else:
+            self.filename_tmpl = '{}'
+
+        if self.io_backend_opt['type'] == 'lmdb':
+            self.io_backend_opt['db_paths'] = [self.lq_folder, self.gt_folder]
+            self.io_backend_opt['client_keys'] = ['lq', 'gt']
+            self.paths = paired_paths_from_lmdb([self.lq_folder, self.gt_folder], ['lq', 'gt'])
+        elif 'meta_info_file' in self.opt and self.opt['meta_info_file'] is not None:
+            self.paths = paired_paths_from_meta_info_file([self.lq_folder, self.gt_folder], ['lq', 'gt'],
+                                                          self.opt['meta_info_file'], self.filename_tmpl)
+        else:
+            self.paths = paired_paths_from_folder([self.lq_folder, self.gt_folder], ['lq', 'gt'], self.filename_tmpl)
+
+    def __getitem__(self, index):
+        if self.file_client is None:
+            self.file_client = FileClient(self.io_backend_opt.pop('type'), **self.io_backend_opt)
+
+        scale = self.opt['scale']
+
+        # Load gt and lq images. Dimension order: HWC; channel order: BGR;
+        # image range: [0, 1], float32.
+        gt_path = self.paths[index]['gt_path']
+        img_bytes = self.file_client.get(gt_path, 'gt')
+        img_gt = imfrombytes(img_bytes, float32=True)
+        lq_path = self.paths[index]['lq_path']
+        img_bytes = self.file_client.get(lq_path, 'lq')
+        img_lq = imfrombytes(img_bytes, float32=True)
+
+        # augmentation for training
+        if self.opt['phase'] == 'train':
+            gt_size = self.opt['gt_size']
+            # random crop
+            img_gt, img_lq = paired_random_crop(img_gt, img_lq, gt_size, scale, gt_path)
+            # flip, rotation
+            img_gt, img_lq = augment([img_gt, img_lq], self.opt['use_flip'], self.opt['use_rot'])
+
+        # TODO: color space transform
+        # BGR to RGB, HWC to CHW, numpy to tensor
+        img_gt, img_lq = img2tensor([img_gt, img_lq], bgr2rgb=True, float32=True)
+        # normalize
+        if self.mean is not None or self.std is not None:
+            normalize(img_lq, self.mean, self.std, inplace=True)
+            normalize(img_gt, self.mean, self.std, inplace=True)
+
+        return {'lq': img_lq, 'gt': img_gt, 'lq_path': lq_path, 'gt_path': gt_path}
+
+    def __len__(self):
+        return len(self.paths)

basicsr/data/prefetch_dataloader.py

@@ -0,0 +1,125 @@
+import queue as Queue
+import threading
+import torch
+from torch.utils.data import DataLoader
+
+
+class PrefetchGenerator(threading.Thread):
+    """A general prefetch generator.
+
+    Ref:
+    https://stackoverflow.com/questions/7323664/python-generator-pre-fetch
+
+    Args:
+        generator: Python generator.
+        num_prefetch_queue (int): Number of prefetch queue.
+    """
+
+    def __init__(self, generator, num_prefetch_queue):
+        threading.Thread.__init__(self)
+        self.queue = Queue.Queue(num_prefetch_queue)
+        self.generator = generator
+        self.daemon = True
+        self.start()
+
+    def run(self):
+        for item in self.generator:
+            self.queue.put(item)
+        self.queue.put(None)
+
+    def __next__(self):
+        next_item = self.queue.get()
+        if next_item is None:
+            raise StopIteration
+        return next_item
+
+    def __iter__(self):
+        return self
+
+
+class PrefetchDataLoader(DataLoader):
+    """Prefetch version of dataloader.
+
+    Ref:
+    https://github.com/IgorSusmelj/pytorch-styleguide/issues/5#
+
+    TODO:
+    Need to test on single gpu and ddp (multi-gpu). There is a known issue in
+    ddp.
+
+    Args:
+        num_prefetch_queue (int): Number of prefetch queue.
+        kwargs (dict): Other arguments for dataloader.
+    """
+
+    def __init__(self, num_prefetch_queue, **kwargs):
+        self.num_prefetch_queue = num_prefetch_queue
+        super(PrefetchDataLoader, self).__init__(**kwargs)
+
+    def __iter__(self):
+        return PrefetchGenerator(super().__iter__(), self.num_prefetch_queue)
+
+
+class CPUPrefetcher():
+    """CPU prefetcher.
+
+    Args:
+        loader: Dataloader.
+    """
+
+    def __init__(self, loader):
+        self.ori_loader = loader
+        self.loader = iter(loader)
+
+    def next(self):
+        try:
+            return next(self.loader)
+        except StopIteration:
+            return None
+
+    def reset(self):
+        self.loader = iter(self.ori_loader)
+
+
+class CUDAPrefetcher():
+    """CUDA prefetcher.
+
+    Ref:
+    https://github.com/NVIDIA/apex/issues/304#
+
+    It may consums more GPU memory.
+
+    Args:
+        loader: Dataloader.
+        opt (dict): Options.
+    """
+
+    def __init__(self, loader, opt):
+        self.ori_loader = loader
+        self.loader = iter(loader)
+        self.opt = opt
+        self.stream = torch.cuda.Stream()
+        self.device = torch.device('cuda' if opt['num_gpu'] != 0 else 'cpu')
+        self.preload()
+
+    def preload(self):
+        try:
+            self.batch = next(self.loader)  # self.batch is a dict
+        except StopIteration:
+            self.batch = None
+            return None
+        # put tensors to gpu
+        with torch.cuda.stream(self.stream):
+            for k, v in self.batch.items():
+                if torch.is_tensor(v):
+                    self.batch[k] = self.batch[k].to(device=self.device, non_blocking=True)
+
+    def next(self):
+        torch.cuda.current_stream().wait_stream(self.stream)
+        batch = self.batch
+        self.preload()
+        return batch
+
+    def reset(self):
+        self.loader = iter(self.ori_loader)
+        self.preload()

basicsr/data/transforms.py

@@ -0,0 +1,165 @@
+import cv2
+import random
+
+
+def mod_crop(img, scale):
+    """Mod crop images, used during testing.
+
+    Args:
+        img (ndarray): Input image.
+        scale (int): Scale factor.
+
+    Returns:
+        ndarray: Result image.
+    """
+    img = img.copy()
+    if img.ndim in (2, 3):
+        h, w = img.shape[0], img.shape[1]
+        h_remainder, w_remainder = h % scale, w % scale
+        img = img[:h - h_remainder, :w - w_remainder, ...]
+    else:
+        raise ValueError(f'Wrong img ndim: {img.ndim}.')
+    return img
+
+
+def paired_random_crop(img_gts, img_lqs, gt_patch_size, scale, gt_path):
+    """Paired random crop.
+
+    It crops lists of lq and gt images with corresponding locations.
+
+    Args:
+        img_gts (list[ndarray] | ndarray): GT images. Note that all images
+            should have the same shape. If the input is an ndarray, it will
+            be transformed to a list containing itself.
+        img_lqs (list[ndarray] | ndarray): LQ images. Note that all images
+            should have the same shape. If the input is an ndarray, it will
+            be transformed to a list containing itself.
+        gt_patch_size (int): GT patch size.
+        scale (int): Scale factor.
+        gt_path (str): Path to ground-truth.
+
+    Returns:
+        list[ndarray] | ndarray: GT images and LQ images. If returned results
+            only have one element, just return ndarray.
+    """
+
+    if not isinstance(img_gts, list):
+        img_gts = [img_gts]
+    if not isinstance(img_lqs, list):
+        img_lqs = [img_lqs]
+
+    h_lq, w_lq, _ = img_lqs[0].shape
+    h_gt, w_gt, _ = img_gts[0].shape
+    lq_patch_size = gt_patch_size // scale
+
+    if h_gt != h_lq * scale or w_gt != w_lq * scale:
+        raise ValueError(f'Scale mismatches. GT ({h_gt}, {w_gt}) is not {scale}x ',
+                         f'multiplication of LQ ({h_lq}, {w_lq}).')
+    if h_lq < lq_patch_size or w_lq < lq_patch_size:
+        raise ValueError(f'LQ ({h_lq}, {w_lq}) is smaller than patch size '
+                         f'({lq_patch_size}, {lq_patch_size}). '
+                         f'Please remove {gt_path}.')
+
+    # randomly choose top and left coordinates for lq patch
+    top = random.randint(0, h_lq - lq_patch_size)
+    left = random.randint(0, w_lq - lq_patch_size)
+
+    # crop lq patch
+    img_lqs = [v[top:top + lq_patch_size, left:left + lq_patch_size, ...] for v in img_lqs]
+
+    # crop corresponding gt patch
+    top_gt, left_gt = int(top * scale), int(left * scale)
+    img_gts = [v[top_gt:top_gt + gt_patch_size, left_gt:left_gt + gt_patch_size, ...] for v in img_gts]
+    if len(img_gts) == 1:
+        img_gts = img_gts[0]
+    if len(img_lqs) == 1:
+        img_lqs = img_lqs[0]
+    return img_gts, img_lqs
+
+
+def augment(imgs, hflip=True, rotation=True, flows=None, return_status=False):
+    """Augment: horizontal flips OR rotate (0, 90, 180, 270 degrees).
+
+    We use vertical flip and transpose for rotation implementation.
+    All the images in the list use the same augmentation.
+
+    Args:
+        imgs (list[ndarray] | ndarray): Images to be augmented. If the input
+            is an ndarray, it will be transformed to a list.
+        hflip (bool): Horizontal flip. Default: True.
+        rotation (bool): Ratotation. Default: True.
+        flows (list[ndarray]: Flows to be augmented. If the input is an
+            ndarray, it will be transformed to a list.
+            Dimension is (h, w, 2). Default: None.
+        return_status (bool): Return the status of flip and rotation.
+            Default: False.
+
+    Returns:
+        list[ndarray] | ndarray: Augmented images and flows. If returned
+            results only have one element, just return ndarray.
+
+    """
+    hflip = hflip and random.random() < 0.5
+    vflip = rotation and random.random() < 0.5
+    rot90 = rotation and random.random() < 0.5
+
+    def _augment(img):
+        if hflip:  # horizontal
+            cv2.flip(img, 1, img)
+        if vflip:  # vertical
+            cv2.flip(img, 0, img)
+        if rot90:
+            img = img.transpose(1, 0, 2)
+        return img
+
+    def _augment_flow(flow):
+        if hflip:  # horizontal
+            cv2.flip(flow, 1, flow)
+            flow[:, :, 0] *= -1
+        if vflip:  # vertical
+            cv2.flip(flow, 0, flow)
+            flow[:, :, 1] *= -1
+        if rot90:
+            flow = flow.transpose(1, 0, 2)
+            flow = flow[:, :, [1, 0]]
+        return flow
+
+    if not isinstance(imgs, list):
+        imgs = [imgs]
+    imgs = [_augment(img) for img in imgs]
+    if len(imgs) == 1:
+        imgs = imgs[0]
+
+    if flows is not None:
+        if not isinstance(flows, list):
+            flows = [flows]
+        flows = [_augment_flow(flow) for flow in flows]
+        if len(flows) == 1:
+            flows = flows[0]
+        return imgs, flows
+    else:
+        if return_status:
+            return imgs, (hflip, vflip, rot90)
+        else:
+            return imgs
+
+
+def img_rotate(img, angle, center=None, scale=1.0):
+    """Rotate image.
+
+    Args:
+        img (ndarray): Image to be rotated.
+        angle (float): Rotation angle in degrees. Positive values mean
+            counter-clockwise rotation.
+        center (tuple[int]): Rotation center. If the center is None,
+            initialize it as the center of the image. Default: None.
+        scale (float): Isotropic scale factor. Default: 1.0.
+    """
+    (h, w) = img.shape[:2]
+
+    if center is None:
+        center = (w // 2, h // 2)
+
+    matrix = cv2.getRotationMatrix2D(center, angle, scale)
+    rotated_img = cv2.warpAffine(img, matrix, (w, h))
+    return rotated_img

basicsr/losses/__init__.py

@@ -0,0 +1,26 @@
+from copy import deepcopy
+
+from basicsr.utils import get_root_logger
+from basicsr.utils.registry import LOSS_REGISTRY
+from .losses import (CharbonnierLoss, GANLoss, L1Loss, MSELoss, PerceptualLoss, WeightedTVLoss, g_path_regularize,
+                     gradient_penalty_loss, r1_penalty)
+
+__all__ = [
+    'L1Loss', 'MSELoss', 'CharbonnierLoss', 'WeightedTVLoss', 'PerceptualLoss', 'GANLoss', 'gradient_penalty_loss',
+    'r1_penalty', 'g_path_regularize'
+]
+
+
+def build_loss(opt):
+    """Build loss from options.
+
+    Args:
+        opt (dict): Configuration. It must constain:
+            type (str): Model type.
+    """
+    opt = deepcopy(opt)
+    loss_type = opt.pop('type')
+    loss = LOSS_REGISTRY.get(loss_type)(**opt)
+    logger = get_root_logger()
+    logger.info(f'Loss [{loss.__class__.__name__}] is created.')
+    return loss

basicsr/losses/loss_util.py

@@ -0,0 +1,95 @@
+import functools
+from torch.nn import functional as F
+
+
+def reduce_loss(loss, reduction):
+    """Reduce loss as specified.
+
+    Args:
+        loss (Tensor): Elementwise loss tensor.
+        reduction (str): Options are 'none', 'mean' and 'sum'.
+
+    Returns:
+        Tensor: Reduced loss tensor.
+    """
+    reduction_enum = F._Reduction.get_enum(reduction)
+    # none: 0, elementwise_mean:1, sum: 2
+    if reduction_enum == 0:
+        return loss
+    elif reduction_enum == 1:
+        return loss.mean()
+    else:
+        return loss.sum()
+
+
+def weight_reduce_loss(loss, weight=None, reduction='mean'):
+    """Apply element-wise weight and reduce loss.
+
+    Args:
+        loss (Tensor): Element-wise loss.
+        weight (Tensor): Element-wise weights. Default: None.
+        reduction (str): Same as built-in losses of PyTorch. Options are
+            'none', 'mean' and 'sum'. Default: 'mean'.
+
+    Returns:
+        Tensor: Loss values.
+    """
+    # if weight is specified, apply element-wise weight
+    if weight is not None:
+        assert weight.dim() == loss.dim()
+        assert weight.size(1) == 1 or weight.size(1) == loss.size(1)
+        loss = loss * weight
+
+    # if weight is not specified or reduction is sum, just reduce the loss
+    if weight is None or reduction == 'sum':
+        loss = reduce_loss(loss, reduction)
+    # if reduction is mean, then compute mean over weight region
+    elif reduction == 'mean':
+        if weight.size(1) > 1:
+            weight = weight.sum()
+        else:
+            weight = weight.sum() * loss.size(1)
+        loss = loss.sum() / weight
+
+    return loss
+
+
+def weighted_loss(loss_func):
+    """Create a weighted version of a given loss function.
+
+    To use this decorator, the loss function must have the signature like
+    `loss_func(pred, target, **kwargs)`. The function only needs to compute
+    element-wise loss without any reduction. This decorator will add weight
+    and reduction arguments to the function. The decorated function will have
+    the signature like `loss_func(pred, target, weight=None, reduction='mean',
+    **kwargs)`.
+
+    :Example:
+
+    >>> import torch
+    >>> @weighted_loss
+    >>> def l1_loss(pred, target):
+    >>>     return (pred - target).abs()
+
+    >>> pred = torch.Tensor([0, 2, 3])
+    >>> target = torch.Tensor([1, 1, 1])
+    >>> weight = torch.Tensor([1, 0, 1])
+
+    >>> l1_loss(pred, target)
+    tensor(1.3333)
+    >>> l1_loss(pred, target, weight)
+    tensor(1.5000)
+    >>> l1_loss(pred, target, reduction='none')
+    tensor([1., 1., 2.])
+    >>> l1_loss(pred, target, weight, reduction='sum')
+    tensor(3.)
+    """
+
+    @functools.wraps(loss_func)
+    def wrapper(pred, target, weight=None, reduction='mean', **kwargs):
+        # get element-wise loss
+        loss = loss_func(pred, target, **kwargs)
+        loss = weight_reduce_loss(loss, weight, reduction)
+        return loss
+
+    return wrapper

basicsr/losses/losses.py

@@ -0,0 +1,455 @@
+import math
+import lpips
+import torch
+from torch import autograd as autograd
+from torch import nn as nn
+from torch.nn import functional as F
+
+from basicsr.archs.vgg_arch import VGGFeatureExtractor
+from basicsr.utils.registry import LOSS_REGISTRY
+from .loss_util import weighted_loss
+
+_reduction_modes = ['none', 'mean', 'sum']
+
+
+@weighted_loss
+def l1_loss(pred, target):
+    return F.l1_loss(pred, target, reduction='none')
+
+
+@weighted_loss
+def mse_loss(pred, target):
+    return F.mse_loss(pred, target, reduction='none')
+
+
+@weighted_loss
+def charbonnier_loss(pred, target, eps=1e-12):
+    return torch.sqrt((pred - target)**2 + eps)
+
+
+@LOSS_REGISTRY.register()
+class L1Loss(nn.Module):
+    """L1 (mean absolute error, MAE) loss.
+
+    Args:
+        loss_weight (float): Loss weight for L1 loss. Default: 1.0.
+        reduction (str): Specifies the reduction to apply to the output.
+            Supported choices are 'none' | 'mean' | 'sum'. Default: 'mean'.
+    """
+
+    def __init__(self, loss_weight=1.0, reduction='mean'):
+        super(L1Loss, self).__init__()
+        if reduction not in ['none', 'mean', 'sum']:
+            raise ValueError(f'Unsupported reduction mode: {reduction}. ' f'Supported ones are: {_reduction_modes}')
+
+        self.loss_weight = loss_weight
+        self.reduction = reduction
+
+    def forward(self, pred, target, weight=None, **kwargs):
+        """
+        Args:
+            pred (Tensor): of shape (N, C, H, W). Predicted tensor.
+            target (Tensor): of shape (N, C, H, W). Ground truth tensor.
+            weight (Tensor, optional): of shape (N, C, H, W). Element-wise
+                weights. Default: None.
+        """
+        return self.loss_weight * l1_loss(pred, target, weight, reduction=self.reduction)
+
+
+@LOSS_REGISTRY.register()
+class MSELoss(nn.Module):
+    """MSE (L2) loss.
+
+    Args:
+        loss_weight (float): Loss weight for MSE loss. Default: 1.0.
+        reduction (str): Specifies the reduction to apply to the output.
+            Supported choices are 'none' | 'mean' | 'sum'. Default: 'mean'.
+    """
+
+    def __init__(self, loss_weight=1.0, reduction='mean'):
+        super(MSELoss, self).__init__()
+        if reduction not in ['none', 'mean', 'sum']:
+            raise ValueError(f'Unsupported reduction mode: {reduction}. ' f'Supported ones are: {_reduction_modes}')
+
+        self.loss_weight = loss_weight
+        self.reduction = reduction
+
+    def forward(self, pred, target, weight=None, **kwargs):
+        """
+        Args:
+            pred (Tensor): of shape (N, C, H, W). Predicted tensor.
+            target (Tensor): of shape (N, C, H, W). Ground truth tensor.
+            weight (Tensor, optional): of shape (N, C, H, W). Element-wise
+                weights. Default: None.
+        """
+        return self.loss_weight * mse_loss(pred, target, weight, reduction=self.reduction)
+
+
+@LOSS_REGISTRY.register()
+class CharbonnierLoss(nn.Module):
+    """Charbonnier loss (one variant of Robust L1Loss, a differentiable
+    variant of L1Loss).
+
+    Described in "Deep Laplacian Pyramid Networks for Fast and Accurate
+        Super-Resolution".
+
+    Args:
+        loss_weight (float): Loss weight for L1 loss. Default: 1.0.
+        reduction (str): Specifies the reduction to apply to the output.
+            Supported choices are 'none' | 'mean' | 'sum'. Default: 'mean'.
+        eps (float): A value used to control the curvature near zero.
+            Default: 1e-12.
+    """
+
+    def __init__(self, loss_weight=1.0, reduction='mean', eps=1e-12):
+        super(CharbonnierLoss, self).__init__()
+        if reduction not in ['none', 'mean', 'sum']:
+            raise ValueError(f'Unsupported reduction mode: {reduction}. ' f'Supported ones are: {_reduction_modes}')
+
+        self.loss_weight = loss_weight
+        self.reduction = reduction
+        self.eps = eps
+
+    def forward(self, pred, target, weight=None, **kwargs):
+        """
+        Args:
+            pred (Tensor): of shape (N, C, H, W). Predicted tensor.
+            target (Tensor): of shape (N, C, H, W). Ground truth tensor.
+            weight (Tensor, optional): of shape (N, C, H, W). Element-wise
+                weights. Default: None.
+        """
+        return self.loss_weight * charbonnier_loss(pred, target, weight, eps=self.eps, reduction=self.reduction)
+
+
+@LOSS_REGISTRY.register()
+class WeightedTVLoss(L1Loss):
+    """Weighted TV loss.
+
+        Args:
+            loss_weight (float): Loss weight. Default: 1.0.
+    """
+
+    def __init__(self, loss_weight=1.0):
+        super(WeightedTVLoss, self).__init__(loss_weight=loss_weight)
+
+    def forward(self, pred, weight=None):
+        y_diff = super(WeightedTVLoss, self).forward(pred[:, :, :-1, :], pred[:, :, 1:, :], weight=weight[:, :, :-1, :])
+        x_diff = super(WeightedTVLoss, self).forward(pred[:, :, :, :-1], pred[:, :, :, 1:], weight=weight[:, :, :, :-1])
+
+        loss = x_diff + y_diff
+
+        return loss
+
+
+@LOSS_REGISTRY.register()
+class PerceptualLoss(nn.Module):
+    """Perceptual loss with commonly used style loss.
+
+    Args:
+        layer_weights (dict): The weight for each layer of vgg feature.
+            Here is an example: {'conv5_4': 1.}, which means the conv5_4
+            feature layer (before relu5_4) will be extracted with weight
+            1.0 in calculting losses.
+        vgg_type (str): The type of vgg network used as feature extractor.
+            Default: 'vgg19'.
+        use_input_norm (bool):  If True, normalize the input image in vgg.
+            Default: True.
+        range_norm (bool): If True, norm images with range [-1, 1] to [0, 1].
+            Default: False.
+        perceptual_weight (float): If `perceptual_weight > 0`, the perceptual
+            loss will be calculated and the loss will multiplied by the
+            weight. Default: 1.0.
+        style_weight (float): If `style_weight > 0`, the style loss will be
+            calculated and the loss will multiplied by the weight.
+            Default: 0.
+        criterion (str): Criterion used for perceptual loss. Default: 'l1'.
+    """
+
+    def __init__(self,
+                 layer_weights,
+                 vgg_type='vgg19',
+                 use_input_norm=True,
+                 range_norm=False,
+                 perceptual_weight=1.0,
+                 style_weight=0.,
+                 criterion='l1'):
+        super(PerceptualLoss, self).__init__()
+        self.perceptual_weight = perceptual_weight
+        self.style_weight = style_weight
+        self.layer_weights = layer_weights
+        self.vgg = VGGFeatureExtractor(
+            layer_name_list=list(layer_weights.keys()),
+            vgg_type=vgg_type,
+            use_input_norm=use_input_norm,
+            range_norm=range_norm)
+
+        self.criterion_type = criterion
+        if self.criterion_type == 'l1':
+            self.criterion = torch.nn.L1Loss()
+        elif self.criterion_type == 'l2':
+            self.criterion = torch.nn.L2loss()
+        elif self.criterion_type == 'mse':
+            self.criterion = torch.nn.MSELoss(reduction='mean')
+        elif self.criterion_type == 'fro':
+            self.criterion = None
+        else:
+            raise NotImplementedError(f'{criterion} criterion has not been supported.')
+
+    def forward(self, x, gt):
+        """Forward function.
+
+        Args:
+            x (Tensor): Input tensor with shape (n, c, h, w).
+            gt (Tensor): Ground-truth tensor with shape (n, c, h, w).
+
+        Returns:
+            Tensor: Forward results.
+        """
+        # extract vgg features
+        x_features = self.vgg(x)
+        gt_features = self.vgg(gt.detach())
+
+        # calculate perceptual loss
+        if self.perceptual_weight > 0:
+            percep_loss = 0
+            for k in x_features.keys():
+                if self.criterion_type == 'fro':
+                    percep_loss += torch.norm(x_features[k] - gt_features[k], p='fro') * self.layer_weights[k]
+                else:
+                    percep_loss += self.criterion(x_features[k], gt_features[k]) * self.layer_weights[k]
+            percep_loss *= self.perceptual_weight
+        else:
+            percep_loss = None
+
+        # calculate style loss
+        if self.style_weight > 0:
+            style_loss = 0
+            for k in x_features.keys():
+                if self.criterion_type == 'fro':
+                    style_loss += torch.norm(
+                        self._gram_mat(x_features[k]) - self._gram_mat(gt_features[k]), p='fro') * self.layer_weights[k]
+                else:
+                    style_loss += self.criterion(self._gram_mat(x_features[k]), self._gram_mat(
+                        gt_features[k])) * self.layer_weights[k]
+            style_loss *= self.style_weight
+        else:
+            style_loss = None
+
+        return percep_loss, style_loss
+
+    def _gram_mat(self, x):
+        """Calculate Gram matrix.
+
+        Args:
+            x (torch.Tensor): Tensor with shape of (n, c, h, w).
+
+        Returns:
+            torch.Tensor: Gram matrix.
+        """
+        n, c, h, w = x.size()
+        features = x.view(n, c, w * h)
+        features_t = features.transpose(1, 2)
+        gram = features.bmm(features_t) / (c * h * w)
+        return gram
+
+
+@LOSS_REGISTRY.register()
+class LPIPSLoss(nn.Module):
+    def __init__(self, 
+            loss_weight=1.0, 
+            use_input_norm=True,
+            range_norm=False,):
+        super(LPIPSLoss, self).__init__()
+        self.perceptual = lpips.LPIPS(net="vgg", spatial=False).eval()
+        self.loss_weight = loss_weight
+        self.use_input_norm = use_input_norm
+        self.range_norm = range_norm
+
+        if self.use_input_norm:
+            # the mean is for image with range [0, 1]
+            self.register_buffer('mean', torch.Tensor([0.485, 0.456, 0.406]).view(1, 3, 1, 1))
+            # the std is for image with range [0, 1]
+            self.register_buffer('std', torch.Tensor([0.229, 0.224, 0.225]).view(1, 3, 1, 1))
+
+    def forward(self, pred, target):
+        if self.range_norm:
+            pred   = (pred + 1) / 2
+            target = (target + 1) / 2
+        if self.use_input_norm:
+            pred   = (pred - self.mean) / self.std
+            target = (target - self.mean) / self.std
+        lpips_loss = self.perceptual(target.contiguous(), pred.contiguous())
+        return self.loss_weight * lpips_loss.mean()
+
+
+@LOSS_REGISTRY.register()
+class GANLoss(nn.Module):
+    """Define GAN loss.
+
+    Args:
+        gan_type (str): Support 'vanilla', 'lsgan', 'wgan', 'hinge'.
+        real_label_val (float): The value for real label. Default: 1.0.
+        fake_label_val (float): The value for fake label. Default: 0.0.
+        loss_weight (float): Loss weight. Default: 1.0.
+            Note that loss_weight is only for generators; and it is always 1.0
+            for discriminators.
+    """
+
+    def __init__(self, gan_type, real_label_val=1.0, fake_label_val=0.0, loss_weight=1.0):
+        super(GANLoss, self).__init__()
+        self.gan_type = gan_type
+        self.loss_weight = loss_weight
+        self.real_label_val = real_label_val
+        self.fake_label_val = fake_label_val
+
+        if self.gan_type == 'vanilla':
+            self.loss = nn.BCEWithLogitsLoss()
+        elif self.gan_type == 'lsgan':
+            self.loss = nn.MSELoss()
+        elif self.gan_type == 'wgan':
+            self.loss = self._wgan_loss
+        elif self.gan_type == 'wgan_softplus':
+            self.loss = self._wgan_softplus_loss
+        elif self.gan_type == 'hinge':
+            self.loss = nn.ReLU()
+        else:
+            raise NotImplementedError(f'GAN type {self.gan_type} is not implemented.')
+
+    def _wgan_loss(self, input, target):
+        """wgan loss.
+
+        Args:
+            input (Tensor): Input tensor.
+            target (bool): Target label.
+
+        Returns:
+            Tensor: wgan loss.
+        """
+        return -input.mean() if target else input.mean()
+
+    def _wgan_softplus_loss(self, input, target):
+        """wgan loss with soft plus. softplus is a smooth approximation to the
+        ReLU function.
+
+        In StyleGAN2, it is called:
+            Logistic loss for discriminator;
+            Non-saturating loss for generator.
+
+        Args:
+            input (Tensor): Input tensor.
+            target (bool): Target label.
+
+        Returns:
+            Tensor: wgan loss.
+        """
+        return F.softplus(-input).mean() if target else F.softplus(input).mean()
+
+    def get_target_label(self, input, target_is_real):
+        """Get target label.
+
+        Args:
+            input (Tensor): Input tensor.
+            target_is_real (bool): Whether the target is real or fake.
+
+        Returns:
+            (bool | Tensor): Target tensor. Return bool for wgan, otherwise,
+                return Tensor.
+        """
+
+        if self.gan_type in ['wgan', 'wgan_softplus']:
+            return target_is_real
+        target_val = (self.real_label_val if target_is_real else self.fake_label_val)
+        return input.new_ones(input.size()) * target_val
+
+    def forward(self, input, target_is_real, is_disc=False):
+        """
+        Args:
+            input (Tensor): The input for the loss module, i.e., the network
+                prediction.
+            target_is_real (bool): Whether the targe is real or fake.
+            is_disc (bool): Whether the loss for discriminators or not.
+                Default: False.
+
+        Returns:
+            Tensor: GAN loss value.
+        """
+        if self.gan_type == 'hinge':
+            if is_disc:  # for discriminators in hinge-gan
+                input = -input if target_is_real else input
+                loss = self.loss(1 + input).mean()
+            else:  # for generators in hinge-gan
+                loss = -input.mean()
+        else:  # other gan types
+            target_label = self.get_target_label(input, target_is_real)
+            loss = self.loss(input, target_label)
+
+        # loss_weight is always 1.0 for discriminators
+        return loss if is_disc else loss * self.loss_weight
+
+
+def r1_penalty(real_pred, real_img):
+    """R1 regularization for discriminator. The core idea is to
+        penalize the gradient on real data alone: when the
+        generator distribution produces the true data distribution
+        and the discriminator is equal to 0 on the data manifold, the
+        gradient penalty ensures that the discriminator cannot create
+        a non-zero gradient orthogonal to the data manifold without
+        suffering a loss in the GAN game.
+
+        Ref:
+        Eq. 9 in Which training methods for GANs do actually converge.
+        """
+    grad_real = autograd.grad(outputs=real_pred.sum(), inputs=real_img, create_graph=True)[0]
+    grad_penalty = grad_real.pow(2).view(grad_real.shape[0], -1).sum(1).mean()
+    return grad_penalty
+
+
+def g_path_regularize(fake_img, latents, mean_path_length, decay=0.01):
+    noise = torch.randn_like(fake_img) / math.sqrt(fake_img.shape[2] * fake_img.shape[3])
+    grad = autograd.grad(outputs=(fake_img * noise).sum(), inputs=latents, create_graph=True)[0]
+    path_lengths = torch.sqrt(grad.pow(2).sum(2).mean(1))
+
+    path_mean = mean_path_length + decay * (path_lengths.mean() - mean_path_length)
+
+    path_penalty = (path_lengths - path_mean).pow(2).mean()
+
+    return path_penalty, path_lengths.detach().mean(), path_mean.detach()
+
+
+def gradient_penalty_loss(discriminator, real_data, fake_data, weight=None):
+    """Calculate gradient penalty for wgan-gp.
+
+    Args:
+        discriminator (nn.Module): Network for the discriminator.
+        real_data (Tensor): Real input data.
+        fake_data (Tensor): Fake input data.
+        weight (Tensor): Weight tensor. Default: None.
+
+    Returns:
+        Tensor: A tensor for gradient penalty.
+    """
+
+    batch_size = real_data.size(0)
+    alpha = real_data.new_tensor(torch.rand(batch_size, 1, 1, 1))
+
+    # interpolate between real_data and fake_data
+    interpolates = alpha * real_data + (1. - alpha) * fake_data
+    interpolates = autograd.Variable(interpolates, requires_grad=True)
+
+    disc_interpolates = discriminator(interpolates)
+    gradients = autograd.grad(
+        outputs=disc_interpolates,
+        inputs=interpolates,
+        grad_outputs=torch.ones_like(disc_interpolates),
+        create_graph=True,
+        retain_graph=True,
+        only_inputs=True)[0]
+
+    if weight is not None:
+        gradients = gradients * weight
+
+    gradients_penalty = ((gradients.norm(2, dim=1) - 1)**2).mean()
+    if weight is not None:
+        gradients_penalty /= torch.mean(weight)
+
+    return gradients_penalty

basicsr/metrics/__init__.py

@@ -0,0 +1,19 @@
+from copy import deepcopy
+
+from basicsr.utils.registry import METRIC_REGISTRY
+from .psnr_ssim import calculate_psnr, calculate_ssim
+
+__all__ = ['calculate_psnr', 'calculate_ssim']
+
+
+def calculate_metric(data, opt):
+    """Calculate metric from data and options.
+
+    Args:
+        opt (dict): Configuration. It must constain:
+            type (str): Model type.
+    """
+    opt = deepcopy(opt)
+    metric_type = opt.pop('type')
+    metric = METRIC_REGISTRY.get(metric_type)(**data, **opt)
+    return metric

basicsr/metrics/metric_util.py

@@ -0,0 +1,45 @@
+import numpy as np
+
+from basicsr.utils.matlab_functions import bgr2ycbcr
+
+
+def reorder_image(img, input_order='HWC'):
+    """Reorder images to 'HWC' order.
+
+    If the input_order is (h, w), return (h, w, 1);
+    If the input_order is (c, h, w), return (h, w, c);
+    If the input_order is (h, w, c), return as it is.
+
+    Args:
+        img (ndarray): Input image.
+        input_order (str): Whether the input order is 'HWC' or 'CHW'.
+            If the input image shape is (h, w), input_order will not have
+            effects. Default: 'HWC'.
+
+    Returns:
+        ndarray: reordered image.
+    """
+
+    if input_order not in ['HWC', 'CHW']:
+        raise ValueError(f'Wrong input_order {input_order}. Supported input_orders are ' "'HWC' and 'CHW'")
+    if len(img.shape) == 2:
+        img = img[..., None]
+    if input_order == 'CHW':
+        img = img.transpose(1, 2, 0)
+    return img
+
+
+def to_y_channel(img):
+    """Change to Y channel of YCbCr.
+
+    Args:
+        img (ndarray): Images with range [0, 255].
+
+    Returns:
+        (ndarray): Images with range [0, 255] (float type) without round.
+    """
+    img = img.astype(np.float32) / 255.
+    if img.ndim == 3 and img.shape[2] == 3:
+        img = bgr2ycbcr(img, y_only=True)
+        img = img[..., None]
+    return img * 255.

basicsr/metrics/psnr_ssim.py

@@ -0,0 +1,128 @@
+import cv2
+import numpy as np
+
+from basicsr.metrics.metric_util import reorder_image, to_y_channel
+from basicsr.utils.registry import METRIC_REGISTRY
+
+
+@METRIC_REGISTRY.register()
+def calculate_psnr(img1, img2, crop_border, input_order='HWC', test_y_channel=False):
+    """Calculate PSNR (Peak Signal-to-Noise Ratio).
+
+    Ref: https://en.wikipedia.org/wiki/Peak_signal-to-noise_ratio
+
+    Args:
+        img1 (ndarray): Images with range [0, 255].
+        img2 (ndarray): Images with range [0, 255].
+        crop_border (int): Cropped pixels in each edge of an image. These
+            pixels are not involved in the PSNR calculation.
+        input_order (str): Whether the input order is 'HWC' or 'CHW'.
+            Default: 'HWC'.
+        test_y_channel (bool): Test on Y channel of YCbCr. Default: False.
+
+    Returns:
+        float: psnr result.
+    """
+
+    assert img1.shape == img2.shape, (f'Image shapes are differnet: {img1.shape}, {img2.shape}.')
+    if input_order not in ['HWC', 'CHW']:
+        raise ValueError(f'Wrong input_order {input_order}. Supported input_orders are ' '"HWC" and "CHW"')
+    img1 = reorder_image(img1, input_order=input_order)
+    img2 = reorder_image(img2, input_order=input_order)
+    img1 = img1.astype(np.float64)
+    img2 = img2.astype(np.float64)
+
+    if crop_border != 0:
+        img1 = img1[crop_border:-crop_border, crop_border:-crop_border, ...]
+        img2 = img2[crop_border:-crop_border, crop_border:-crop_border, ...]
+
+    if test_y_channel:
+        img1 = to_y_channel(img1)
+        img2 = to_y_channel(img2)
+
+    mse = np.mean((img1 - img2)**2)
+    if mse == 0:
+        return float('inf')
+    return 20. * np.log10(255. / np.sqrt(mse))
+
+
+def _ssim(img1, img2):
+    """Calculate SSIM (structural similarity) for one channel images.
+
+    It is called by func:`calculate_ssim`.
+
+    Args:
+        img1 (ndarray): Images with range [0, 255] with order 'HWC'.
+        img2 (ndarray): Images with range [0, 255] with order 'HWC'.
+
+    Returns:
+        float: ssim result.
+    """
+
+    C1 = (0.01 * 255)**2
+    C2 = (0.03 * 255)**2
+
+    img1 = img1.astype(np.float64)
+    img2 = img2.astype(np.float64)
+    kernel = cv2.getGaussianKernel(11, 1.5)
+    window = np.outer(kernel, kernel.transpose())
+
+    mu1 = cv2.filter2D(img1, -1, window)[5:-5, 5:-5]
+    mu2 = cv2.filter2D(img2, -1, window)[5:-5, 5:-5]
+    mu1_sq = mu1**2
+    mu2_sq = mu2**2
+    mu1_mu2 = mu1 * mu2
+    sigma1_sq = cv2.filter2D(img1**2, -1, window)[5:-5, 5:-5] - mu1_sq
+    sigma2_sq = cv2.filter2D(img2**2, -1, window)[5:-5, 5:-5] - mu2_sq
+    sigma12 = cv2.filter2D(img1 * img2, -1, window)[5:-5, 5:-5] - mu1_mu2
+
+    ssim_map = ((2 * mu1_mu2 + C1) * (2 * sigma12 + C2)) / ((mu1_sq + mu2_sq + C1) * (sigma1_sq + sigma2_sq + C2))
+    return ssim_map.mean()
+
+
+@METRIC_REGISTRY.register()
+def calculate_ssim(img1, img2, crop_border, input_order='HWC', test_y_channel=False):
+    """Calculate SSIM (structural similarity).
+
+    Ref:
+    Image quality assessment: From error visibility to structural similarity
+
+    The results are the same as that of the official released MATLAB code in
+    https://ece.uwaterloo.ca/~z70wang/research/ssim/.
+
+    For three-channel images, SSIM is calculated for each channel and then
+    averaged.
+
+    Args:
+        img1 (ndarray): Images with range [0, 255].
+        img2 (ndarray): Images with range [0, 255].
+        crop_border (int): Cropped pixels in each edge of an image. These
+            pixels are not involved in the SSIM calculation.
+        input_order (str): Whether the input order is 'HWC' or 'CHW'.
+            Default: 'HWC'.
+        test_y_channel (bool): Test on Y channel of YCbCr. Default: False.
+
+    Returns:
+        float: ssim result.
+    """
+
+    assert img1.shape == img2.shape, (f'Image shapes are differnet: {img1.shape}, {img2.shape}.')
+    if input_order not in ['HWC', 'CHW']:
+        raise ValueError(f'Wrong input_order {input_order}. Supported input_orders are ' '"HWC" and "CHW"')
+    img1 = reorder_image(img1, input_order=input_order)
+    img2 = reorder_image(img2, input_order=input_order)
+    img1 = img1.astype(np.float64)
+    img2 = img2.astype(np.float64)
+
+    if crop_border != 0:
+        img1 = img1[crop_border:-crop_border, crop_border:-crop_border, ...]
+        img2 = img2[crop_border:-crop_border, crop_border:-crop_border, ...]
+
+    if test_y_channel:
+        img1 = to_y_channel(img1)
+        img2 = to_y_channel(img2)
+
+    ssims = []
+    for i in range(img1.shape[2]):
+        ssims.append(_ssim(img1[..., i], img2[..., i]))
+    return np.array(ssims).mean()

basicsr/models/__init__.py

@@ -0,0 +1,30 @@
+import importlib
+from copy import deepcopy
+from os import path as osp
+
+from basicsr.utils import get_root_logger, scandir
+from basicsr.utils.registry import MODEL_REGISTRY
+
+__all__ = ['build_model']
+
+# automatically scan and import model modules for registry
+# scan all the files under the 'models' folder and collect files ending with
+# '_model.py'
+model_folder = osp.dirname(osp.abspath(__file__))
+model_filenames = [osp.splitext(osp.basename(v))[0] for v in scandir(model_folder) if v.endswith('_model.py')]
+# import all the model modules
+_model_modules = [importlib.import_module(f'basicsr.models.{file_name}') for file_name in model_filenames]
+
+
+def build_model(opt):
+    """Build model from options.
+
+    Args:
+        opt (dict): Configuration. It must constain:
+            model_type (str): Model type.
+    """
+    opt = deepcopy(opt)
+    model = MODEL_REGISTRY.get(opt['model_type'])(opt)
+    logger = get_root_logger()
+    logger.info(f'Model [{model.__class__.__name__}] is created.')
+    return model

basicsr/models/base_model.py

@@ -0,0 +1,322 @@
+import logging
+import os
+import torch
+from collections import OrderedDict
+from copy import deepcopy
+from torch.nn.parallel import DataParallel, DistributedDataParallel
+
+from basicsr.models import lr_scheduler as lr_scheduler
+from basicsr.utils.dist_util import master_only
+
+logger = logging.getLogger('basicsr')
+
+
+class BaseModel():
+    """Base model."""
+
+    def __init__(self, opt):
+        self.opt = opt
+        self.device = torch.device('cuda' if opt['num_gpu'] != 0 else 'cpu')
+        self.is_train = opt['is_train']
+        self.schedulers = []
+        self.optimizers = []
+
+    def feed_data(self, data):
+        pass
+
+    def optimize_parameters(self):
+        pass
+
+    def get_current_visuals(self):
+        pass
+
+    def save(self, epoch, current_iter):
+        """Save networks and training state."""
+        pass
+
+    def validation(self, dataloader, current_iter, tb_logger, save_img=False):
+        """Validation function.
+
+        Args:
+            dataloader (torch.utils.data.DataLoader): Validation dataloader.
+            current_iter (int): Current iteration.
+            tb_logger (tensorboard logger): Tensorboard logger.
+            save_img (bool): Whether to save images. Default: False.
+        """
+        if self.opt['dist']:
+            self.dist_validation(dataloader, current_iter, tb_logger, save_img)
+        else:
+            self.nondist_validation(dataloader, current_iter, tb_logger, save_img)
+
+    def model_ema(self, decay=0.999):
+        net_g = self.get_bare_model(self.net_g)
+
+        net_g_params = dict(net_g.named_parameters())
+        net_g_ema_params = dict(self.net_g_ema.named_parameters())
+
+        for k in net_g_ema_params.keys():
+            net_g_ema_params[k].data.mul_(decay).add_(net_g_params[k].data, alpha=1 - decay)
+
+    def get_current_log(self):
+        return self.log_dict
+
+    def model_to_device(self, net):
+        """Model to device. It also warps models with DistributedDataParallel
+        or DataParallel.
+
+        Args:
+            net (nn.Module)
+        """
+        net = net.to(self.device)
+        if self.opt['dist']:
+            find_unused_parameters = self.opt.get('find_unused_parameters', False)
+            net = DistributedDataParallel(
+                net, device_ids=[torch.cuda.current_device()], find_unused_parameters=find_unused_parameters)
+        elif self.opt['num_gpu'] > 1:
+            net = DataParallel(net)
+        return net
+
+    def get_optimizer(self, optim_type, params, lr, **kwargs):
+        if optim_type == 'Adam':
+            optimizer = torch.optim.Adam(params, lr, **kwargs)
+        else:
+            raise NotImplementedError(f'optimizer {optim_type} is not supperted yet.')
+        return optimizer
+
+    def setup_schedulers(self):
+        """Set up schedulers."""
+        train_opt = self.opt['train']
+        scheduler_type = train_opt['scheduler'].pop('type')
+        if scheduler_type in ['MultiStepLR', 'MultiStepRestartLR']:
+            for optimizer in self.optimizers:
+                self.schedulers.append(lr_scheduler.MultiStepRestartLR(optimizer, **train_opt['scheduler']))
+        elif scheduler_type == 'CosineAnnealingRestartLR':
+            for optimizer in self.optimizers:
+                self.schedulers.append(lr_scheduler.CosineAnnealingRestartLR(optimizer, **train_opt['scheduler']))
+        else:
+            raise NotImplementedError(f'Scheduler {scheduler_type} is not implemented yet.')
+
+    def get_bare_model(self, net):
+        """Get bare model, especially under wrapping with
+        DistributedDataParallel or DataParallel.
+        """
+        if isinstance(net, (DataParallel, DistributedDataParallel)):
+            net = net.module
+        return net
+
+    @master_only
+    def print_network(self, net):
+        """Print the str and parameter number of a network.
+
+        Args:
+            net (nn.Module)
+        """
+        if isinstance(net, (DataParallel, DistributedDataParallel)):
+            net_cls_str = (f'{net.__class__.__name__} - ' f'{net.module.__class__.__name__}')
+        else:
+            net_cls_str = f'{net.__class__.__name__}'
+
+        net = self.get_bare_model(net)
+        net_str = str(net)
+        net_params = sum(map(lambda x: x.numel(), net.parameters()))
+
+        logger.info(f'Network: {net_cls_str}, with parameters: {net_params:,d}')
+        logger.info(net_str)
+
+    def _set_lr(self, lr_groups_l):
+        """Set learning rate for warmup.
+
+        Args:
+            lr_groups_l (list): List for lr_groups, each for an optimizer.
+        """
+        for optimizer, lr_groups in zip(self.optimizers, lr_groups_l):
+            for param_group, lr in zip(optimizer.param_groups, lr_groups):
+                param_group['lr'] = lr
+
+    def _get_init_lr(self):
+        """Get the initial lr, which is set by the scheduler.
+        """
+        init_lr_groups_l = []
+        for optimizer in self.optimizers:
+            init_lr_groups_l.append([v['initial_lr'] for v in optimizer.param_groups])
+        return init_lr_groups_l
+
+    def update_learning_rate(self, current_iter, warmup_iter=-1):
+        """Update learning rate.
+
+        Args:
+            current_iter (int): Current iteration.
+            warmup_iter (int)： Warmup iter numbers. -1 for no warmup.
+                Default： -1.
+        """
+        if current_iter > 1:
+            for scheduler in self.schedulers:
+                scheduler.step()
+        # set up warm-up learning rate
+        if current_iter < warmup_iter:
+            # get initial lr for each group
+            init_lr_g_l = self._get_init_lr()
+            # modify warming-up learning rates
+            # currently only support linearly warm up
+            warm_up_lr_l = []
+            for init_lr_g in init_lr_g_l:
+                warm_up_lr_l.append([v / warmup_iter * current_iter for v in init_lr_g])
+            # set learning rate
+            self._set_lr(warm_up_lr_l)
+
+    def get_current_learning_rate(self):
+        return [param_group['lr'] for param_group in self.optimizers[0].param_groups]
+
+    @master_only
+    def save_network(self, net, net_label, current_iter, param_key='params'):
+        """Save networks.
+
+        Args:
+            net (nn.Module | list[nn.Module]): Network(s) to be saved.
+            net_label (str): Network label.
+            current_iter (int): Current iter number.
+            param_key (str | list[str]): The parameter key(s) to save network.
+                Default: 'params'.
+        """
+        if current_iter == -1:
+            current_iter = 'latest'
+        save_filename = f'{net_label}_{current_iter}.pth'
+        save_path = os.path.join(self.opt['path']['models'], save_filename)
+
+        net = net if isinstance(net, list) else [net]
+        param_key = param_key if isinstance(param_key, list) else [param_key]
+        assert len(net) == len(param_key), 'The lengths of net and param_key should be the same.'
+
+        save_dict = {}
+        for net_, param_key_ in zip(net, param_key):
+            net_ = self.get_bare_model(net_)
+            state_dict = net_.state_dict()
+            for key, param in state_dict.items():
+                if key.startswith('module.'):  # remove unnecessary 'module.'
+                    key = key[7:]
+                state_dict[key] = param.cpu()
+            save_dict[param_key_] = state_dict
+
+        torch.save(save_dict, save_path)
+
+    def _print_different_keys_loading(self, crt_net, load_net, strict=True):
+        """Print keys with differnet name or different size when loading models.
+
+        1. Print keys with differnet names.
+        2. If strict=False, print the same key but with different tensor size.
+            It also ignore these keys with different sizes (not load).
+
+        Args:
+            crt_net (torch model): Current network.
+            load_net (dict): Loaded network.
+            strict (bool): Whether strictly loaded. Default: True.
+        """
+        crt_net = self.get_bare_model(crt_net)
+        crt_net = crt_net.state_dict()
+        crt_net_keys = set(crt_net.keys())
+        load_net_keys = set(load_net.keys())
+
+        if crt_net_keys != load_net_keys:
+            logger.warning('Current net - loaded net:')
+            for v in sorted(list(crt_net_keys - load_net_keys)):
+                logger.warning(f'  {v}')
+            logger.warning('Loaded net - current net:')
+            for v in sorted(list(load_net_keys - crt_net_keys)):
+                logger.warning(f'  {v}')
+
+        # check the size for the same keys
+        if not strict:
+            common_keys = crt_net_keys & load_net_keys
+            for k in common_keys:
+                if crt_net[k].size() != load_net[k].size():
+                    logger.warning(f'Size different, ignore [{k}]: crt_net: '
+                                   f'{crt_net[k].shape}; load_net: {load_net[k].shape}')
+                    load_net[k + '.ignore'] = load_net.pop(k)
+
+    def load_network(self, net, load_path, strict=True, param_key='params'):
+        """Load network.
+
+        Args:
+            load_path (str): The path of networks to be loaded.
+            net (nn.Module): Network.
+            strict (bool): Whether strictly loaded.
+            param_key (str): The parameter key of loaded network. If set to
+                None, use the root 'path'.
+                Default: 'params'.
+        """
+        net = self.get_bare_model(net)
+        logger.info(f'Loading {net.__class__.__name__} model from {load_path}.')
+        load_net = torch.load(load_path, map_location=lambda storage, loc: storage)
+        if param_key is not None:
+            if param_key not in load_net and 'params' in load_net:
+                param_key = 'params'
+                logger.info('Loading: params_ema does not exist, use params.')
+            load_net = load_net[param_key]
+        # remove unnecessary 'module.'
+        for k, v in deepcopy(load_net).items():
+            if k.startswith('module.'):
+                load_net[k[7:]] = v
+                load_net.pop(k)
+        self._print_different_keys_loading(net, load_net, strict)
+        net.load_state_dict(load_net, strict=strict)
+
+    @master_only
+    def save_training_state(self, epoch, current_iter):
+        """Save training states during training, which will be used for
+        resuming.
+
+        Args:
+            epoch (int): Current epoch.
+            current_iter (int): Current iteration.
+        """
+        if current_iter != -1:
+            state = {'epoch': epoch, 'iter': current_iter, 'optimizers': [], 'schedulers': []}
+            for o in self.optimizers:
+                state['optimizers'].append(o.state_dict())
+            for s in self.schedulers:
+                state['schedulers'].append(s.state_dict())
+            save_filename = f'{current_iter}.state'
+            save_path = os.path.join(self.opt['path']['training_states'], save_filename)
+            torch.save(state, save_path)
+
+    def resume_training(self, resume_state):
+        """Reload the optimizers and schedulers for resumed training.
+
+        Args:
+            resume_state (dict): Resume state.
+        """
+        resume_optimizers = resume_state['optimizers']
+        resume_schedulers = resume_state['schedulers']
+        assert len(resume_optimizers) == len(self.optimizers), 'Wrong lengths of optimizers'
+        assert len(resume_schedulers) == len(self.schedulers), 'Wrong lengths of schedulers'
+        for i, o in enumerate(resume_optimizers):
+            self.optimizers[i].load_state_dict(o)
+        for i, s in enumerate(resume_schedulers):
+            self.schedulers[i].load_state_dict(s)
+
+    def reduce_loss_dict(self, loss_dict):
+        """reduce loss dict.
+
+        In distributed training, it averages the losses among different GPUs .
+
+        Args:
+            loss_dict (OrderedDict): Loss dict.
+        """
+        with torch.no_grad():
+            if self.opt['dist']:
+                keys = []
+                losses = []
+                for name, value in loss_dict.items():
+                    keys.append(name)
+                    losses.append(value)
+                losses = torch.stack(losses, 0)
+                torch.distributed.reduce(losses, dst=0)
+                if self.opt['rank'] == 0:
+                    losses /= self.opt['world_size']
+                loss_dict = {key: loss for key, loss in zip(keys, losses)}
+
+            log_dict = OrderedDict()
+            for name, value in loss_dict.items():
+                log_dict[name] = value.mean().item()
+
+            return log_dict

basicsr/models/codeformer_idx_model.py

@@ -0,0 +1,220 @@
+import torch
+from collections import OrderedDict
+from os import path as osp
+from tqdm import tqdm
+
+from basicsr.archs import build_network
+from basicsr.metrics import calculate_metric
+from basicsr.utils import get_root_logger, imwrite, tensor2img
+from basicsr.utils.registry import MODEL_REGISTRY
+import torch.nn.functional as F
+from .sr_model import SRModel
+
+
+@MODEL_REGISTRY.register()
+class CodeFormerIdxModel(SRModel):
+    def feed_data(self, data):
+        self.gt = data['gt'].to(self.device)
+        self.input = data['in'].to(self.device)
+        self.b = self.gt.shape[0]
+
+        if 'latent_gt' in data:
+            self.idx_gt = data['latent_gt'].to(self.device)
+            self.idx_gt = self.idx_gt.view(self.b, -1)
+        else:
+            self.idx_gt = None
+
+    def init_training_settings(self):
+        logger = get_root_logger()
+        train_opt = self.opt['train']
+
+        self.ema_decay = train_opt.get('ema_decay', 0)
+        if self.ema_decay > 0:
+            logger.info(f'Use Exponential Moving Average with decay: {self.ema_decay}')
+            # define network net_g with Exponential Moving Average (EMA)
+            # net_g_ema is used only for testing on one GPU and saving
+            # There is no need to wrap with DistributedDataParallel
+            self.net_g_ema = build_network(self.opt['network_g']).to(self.device)
+            # load pretrained model
+            load_path = self.opt['path'].get('pretrain_network_g', None)
+            if load_path is not None:
+                self.load_network(self.net_g_ema, load_path, self.opt['path'].get('strict_load_g', True), 'params_ema')
+            else:
+                self.model_ema(0)  # copy net_g weight
+            self.net_g_ema.eval()
+
+        if self.opt['datasets']['train'].get('latent_gt_path', None) is not None:
+            self.generate_idx_gt = False
+        elif self.opt.get('network_vqgan', None) is not None:
+            self.hq_vqgan_fix = build_network(self.opt['network_vqgan']).to(self.device)
+            self.hq_vqgan_fix.eval()
+            self.generate_idx_gt = True
+            for param in self.hq_vqgan_fix.parameters():
+                param.requires_grad = False
+        else:
+            raise NotImplementedError(f'Shoule have network_vqgan config or pre-calculated latent code.')
+        
+        logger.info(f'Need to generate latent GT code: {self.generate_idx_gt}')
+
+        self.hq_feat_loss = train_opt.get('use_hq_feat_loss', True)
+        self.feat_loss_weight = train_opt.get('feat_loss_weight', 1.0)
+        self.cross_entropy_loss = train_opt.get('cross_entropy_loss', True)
+        self.entropy_loss_weight = train_opt.get('entropy_loss_weight', 0.5)
+
+        self.net_g.train()
+
+        # set up optimizers and schedulers
+        self.setup_optimizers()
+        self.setup_schedulers()
+
+
+    def setup_optimizers(self):
+        train_opt = self.opt['train']
+        # optimizer g
+        optim_params_g = []
+        for k, v in self.net_g.named_parameters():
+            if v.requires_grad:
+                optim_params_g.append(v)
+            else:
+                logger = get_root_logger()
+                logger.warning(f'Params {k} will not be optimized.')
+        optim_type = train_opt['optim_g'].pop('type')
+        self.optimizer_g = self.get_optimizer(optim_type, optim_params_g, **train_opt['optim_g'])
+        self.optimizers.append(self.optimizer_g)
+
+
+    def optimize_parameters(self, current_iter):
+        logger = get_root_logger()
+        # optimize net_g
+        self.optimizer_g.zero_grad()
+
+        if self.generate_idx_gt:
+            x = self.hq_vqgan_fix.encoder(self.gt)
+            _, _, quant_stats = self.hq_vqgan_fix.quantize(x)
+            min_encoding_indices = quant_stats['min_encoding_indices']
+            self.idx_gt = min_encoding_indices.view(self.b, -1)
+        
+        if self.hq_feat_loss:
+            # quant_feats
+            quant_feat_gt = self.net_g.module.quantize.get_codebook_feat(self.idx_gt, shape=[self.b,16,16,256])
+
+        logits, lq_feat = self.net_g(self.input, w=0, code_only=True)
+
+        l_g_total = 0
+        loss_dict = OrderedDict()
+        # hq_feat_loss
+        if self.hq_feat_loss: # codebook loss 
+            l_feat_encoder = torch.mean((quant_feat_gt.detach()-lq_feat)**2) * self.feat_loss_weight
+            l_g_total += l_feat_encoder
+            loss_dict['l_feat_encoder'] = l_feat_encoder
+
+        # cross_entropy_loss
+        if self.cross_entropy_loss:
+            # b(hw)n -> bn(hw)
+            cross_entropy_loss = F.cross_entropy(logits.permute(0, 2, 1), self.idx_gt) * self.entropy_loss_weight
+            l_g_total += cross_entropy_loss
+            loss_dict['cross_entropy_loss'] = cross_entropy_loss
+
+        l_g_total.backward()
+        self.optimizer_g.step()
+
+        if self.ema_decay > 0:
+            self.model_ema(decay=self.ema_decay)
+
+        self.log_dict = self.reduce_loss_dict(loss_dict)
+
+
+    def test(self):
+        with torch.no_grad():
+            if hasattr(self, 'net_g_ema'):
+                self.net_g_ema.eval()
+                self.output, _, _ = self.net_g_ema(self.input, w=0)
+            else:
+                logger = get_root_logger()
+                logger.warning('Do not have self.net_g_ema, use self.net_g.')
+                self.net_g.eval()
+                self.output, _, _ = self.net_g(self.input, w=0)
+                self.net_g.train()
+
+
+    def dist_validation(self, dataloader, current_iter, tb_logger, save_img):
+        if self.opt['rank'] == 0:
+            self.nondist_validation(dataloader, current_iter, tb_logger, save_img)
+
+
+    def nondist_validation(self, dataloader, current_iter, tb_logger, save_img):
+        dataset_name = dataloader.dataset.opt['name']
+        with_metrics = self.opt['val'].get('metrics') is not None
+        if with_metrics:
+            self.metric_results = {metric: 0 for metric in self.opt['val']['metrics'].keys()}
+        pbar = tqdm(total=len(dataloader), unit='image')
+
+        for idx, val_data in enumerate(dataloader):
+            img_name = osp.splitext(osp.basename(val_data['lq_path'][0]))[0]
+            self.feed_data(val_data)
+            self.test()
+
+            visuals = self.get_current_visuals()
+            sr_img = tensor2img([visuals['result']])
+            if 'gt' in visuals:
+                gt_img = tensor2img([visuals['gt']])
+                del self.gt
+
+            # tentative for out of GPU memory
+            del self.lq
+            del self.output
+            torch.cuda.empty_cache()
+
+            if save_img:
+                if self.opt['is_train']:
+                    save_img_path = osp.join(self.opt['path']['visualization'], img_name,
+                                             f'{img_name}_{current_iter}.png')
+                else:
+                    if self.opt['val']['suffix']:
+                        save_img_path = osp.join(self.opt['path']['visualization'], dataset_name,
+                                                 f'{img_name}_{self.opt["val"]["suffix"]}.png')
+                    else:
+                        save_img_path = osp.join(self.opt['path']['visualization'], dataset_name,
+                                                 f'{img_name}_{self.opt["name"]}.png')
+                imwrite(sr_img, save_img_path)
+
+            if with_metrics:
+                # calculate metrics
+                for name, opt_ in self.opt['val']['metrics'].items():
+                    metric_data = dict(img1=sr_img, img2=gt_img)
+                    self.metric_results[name] += calculate_metric(metric_data, opt_)
+            pbar.update(1)
+            pbar.set_description(f'Test {img_name}')
+        pbar.close()
+
+        if with_metrics:
+            for metric in self.metric_results.keys():
+                self.metric_results[metric] /= (idx + 1)
+
+            self._log_validation_metric_values(current_iter, dataset_name, tb_logger)
+
+
+    def _log_validation_metric_values(self, current_iter, dataset_name, tb_logger):
+        log_str = f'Validation {dataset_name}\n'
+        for metric, value in self.metric_results.items():
+            log_str += f'\t # {metric}: {value:.4f}\n'
+        logger = get_root_logger()
+        logger.info(log_str)
+        if tb_logger:
+            for metric, value in self.metric_results.items():
+                tb_logger.add_scalar(f'metrics/{metric}', value, current_iter)
+
+
+    def get_current_visuals(self):
+        out_dict = OrderedDict()
+        out_dict['gt'] = self.gt.detach().cpu()
+        out_dict['result'] = self.output.detach().cpu()
+        return out_dict
+
+
+    def save(self, epoch, current_iter):
+        if self.ema_decay > 0:
+            self.save_network([self.net_g, self.net_g_ema], 'net_g', current_iter, param_key=['params', 'params_ema'])
+        else:
+            self.save_network(self.net_g, 'net_g', current_iter)
+        self.save_training_state(epoch, current_iter)

basicsr/models/codeformer_joint_model.py

@@ -0,0 +1,350 @@
+import torch
+from collections import OrderedDict
+from os import path as osp
+from tqdm import tqdm
+
+
+from basicsr.archs import build_network
+from basicsr.losses import build_loss
+from basicsr.metrics import calculate_metric
+from basicsr.utils import get_root_logger, imwrite, tensor2img
+from basicsr.utils.registry import MODEL_REGISTRY
+import torch.nn.functional as F
+from .sr_model import SRModel
+
+
+@MODEL_REGISTRY.register()
+class CodeFormerJointModel(SRModel):
+    def feed_data(self, data):
+        self.gt = data['gt'].to(self.device)
+        self.input = data['in'].to(self.device)
+        self.input_large_de = data['in_large_de'].to(self.device)
+        self.b = self.gt.shape[0]
+
+        if 'latent_gt' in data:
+            self.idx_gt = data['latent_gt'].to(self.device)
+            self.idx_gt = self.idx_gt.view(self.b, -1)
+        else:
+            self.idx_gt = None
+
+    def init_training_settings(self):
+        logger = get_root_logger()
+        train_opt = self.opt['train']
+
+        self.ema_decay = train_opt.get('ema_decay', 0)
+        if self.ema_decay > 0:
+            logger.info(f'Use Exponential Moving Average with decay: {self.ema_decay}')
+            # define network net_g with Exponential Moving Average (EMA)
+            # net_g_ema is used only for testing on one GPU and saving
+            # There is no need to wrap with DistributedDataParallel
+            self.net_g_ema = build_network(self.opt['network_g']).to(self.device)
+            # load pretrained model
+            load_path = self.opt['path'].get('pretrain_network_g', None)
+            if load_path is not None:
+                self.load_network(self.net_g_ema, load_path, self.opt['path'].get('strict_load_g', True), 'params_ema')
+            else:
+                self.model_ema(0)  # copy net_g weight
+            self.net_g_ema.eval()
+
+        if self.opt['datasets']['train'].get('latent_gt_path', None) is not None:
+            self.generate_idx_gt = False
+        elif self.opt.get('network_vqgan', None) is not None:
+            self.hq_vqgan_fix = build_network(self.opt['network_vqgan']).to(self.device)
+            self.hq_vqgan_fix.eval()
+            self.generate_idx_gt = True
+            for param in self.hq_vqgan_fix.parameters():
+                param.requires_grad = False
+        else:
+            raise NotImplementedError(f'Shoule have network_vqgan config or pre-calculated latent code.') 
+        
+        logger.info(f'Need to generate latent GT code: {self.generate_idx_gt}')
+        
+        self.hq_feat_loss = train_opt.get('use_hq_feat_loss', True)
+        self.feat_loss_weight = train_opt.get('feat_loss_weight', 1.0)
+        self.cross_entropy_loss = train_opt.get('cross_entropy_loss', True)
+        self.entropy_loss_weight = train_opt.get('entropy_loss_weight', 0.5)
+        self.scale_adaptive_gan_weight = train_opt.get('scale_adaptive_gan_weight', 0.8)
+
+        # define network net_d
+        self.net_d = build_network(self.opt['network_d'])
+        self.net_d = self.model_to_device(self.net_d)
+        self.print_network(self.net_d)
+
+        # load pretrained models
+        load_path = self.opt['path'].get('pretrain_network_d', None)
+        if load_path is not None:
+            self.load_network(self.net_d, load_path, self.opt['path'].get('strict_load_d', True))
+
+        self.net_g.train()
+        self.net_d.train()
+
+        # define losses
+        if train_opt.get('pixel_opt'):
+            self.cri_pix = build_loss(train_opt['pixel_opt']).to(self.device)
+        else:
+            self.cri_pix = None
+
+        if train_opt.get('perceptual_opt'):
+            self.cri_perceptual = build_loss(train_opt['perceptual_opt']).to(self.device)
+        else:
+            self.cri_perceptual = None
+
+        if train_opt.get('gan_opt'):
+            self.cri_gan = build_loss(train_opt['gan_opt']).to(self.device)
+
+
+        self.fix_generator = train_opt.get('fix_generator', True)
+        logger.info(f'fix_generator: {self.fix_generator}')
+
+        self.net_g_start_iter = train_opt.get('net_g_start_iter', 0)
+        self.net_d_iters = train_opt.get('net_d_iters', 1)
+        self.net_d_start_iter = train_opt.get('net_d_start_iter', 0)
+
+        # set up optimizers and schedulers
+        self.setup_optimizers()
+        self.setup_schedulers()
+
+    def calculate_adaptive_weight(self, recon_loss, g_loss, last_layer, disc_weight_max):
+        recon_grads = torch.autograd.grad(recon_loss, last_layer, retain_graph=True)[0]
+        g_grads = torch.autograd.grad(g_loss, last_layer, retain_graph=True)[0]
+
+        d_weight = torch.norm(recon_grads) / (torch.norm(g_grads) + 1e-4)
+        d_weight = torch.clamp(d_weight, 0.0, disc_weight_max).detach()
+        return d_weight
+
+    def setup_optimizers(self):
+        train_opt = self.opt['train']
+        # optimizer g
+        optim_params_g = []
+        for k, v in self.net_g.named_parameters():
+            if v.requires_grad:
+                optim_params_g.append(v)
+            else:
+                logger = get_root_logger()
+                logger.warning(f'Params {k} will not be optimized.')
+        optim_type = train_opt['optim_g'].pop('type')
+        self.optimizer_g = self.get_optimizer(optim_type, optim_params_g, **train_opt['optim_g'])
+        self.optimizers.append(self.optimizer_g)
+        # optimizer d
+        optim_type = train_opt['optim_d'].pop('type')
+        self.optimizer_d = self.get_optimizer(optim_type, self.net_d.parameters(), **train_opt['optim_d'])
+        self.optimizers.append(self.optimizer_d)
+
+    def gray_resize_for_identity(self, out, size=128):
+        out_gray = (0.2989 * out[:, 0, :, :] + 0.5870 * out[:, 1, :, :] + 0.1140 * out[:, 2, :, :])
+        out_gray = out_gray.unsqueeze(1)
+        out_gray = F.interpolate(out_gray, (size, size), mode='bilinear', align_corners=False)
+        return out_gray
+
+    def optimize_parameters(self, current_iter):
+        logger = get_root_logger()
+        # optimize net_g
+        for p in self.net_d.parameters():
+            p.requires_grad = False
+
+        self.optimizer_g.zero_grad()
+
+        if self.generate_idx_gt:
+            x = self.hq_vqgan_fix.encoder(self.gt)
+            output, _, quant_stats = self.hq_vqgan_fix.quantize(x)
+            min_encoding_indices = quant_stats['min_encoding_indices']
+            self.idx_gt = min_encoding_indices.view(self.b, -1)
+
+        if current_iter <= 40000: # small degradation
+            small_per_n = 1
+            w = 1
+        elif current_iter <= 80000: # small degradation
+            small_per_n = 1
+            w = 1.3            
+        elif current_iter <= 120000: # large degradation
+            small_per_n = 120000
+            w = 0     
+        else: # mixed degradation
+            small_per_n = 15
+            w = 1.3
+
+        if current_iter % small_per_n == 0:
+            self.output, logits, lq_feat = self.net_g(self.input, w=w, detach_16=True)
+            large_de = False
+        else:
+            logits, lq_feat = self.net_g(self.input_large_de, code_only=True)
+            large_de = True
+
+        if self.hq_feat_loss:
+            # quant_feats
+            quant_feat_gt = self.net_g.module.quantize.get_codebook_feat(self.idx_gt, shape=[self.b,16,16,256])
+
+        l_g_total = 0
+        loss_dict = OrderedDict()
+        if current_iter % self.net_d_iters == 0 and current_iter > self.net_g_start_iter:
+            # hq_feat_loss
+            if not 'transformer' in self.opt['network_g']['fix_modules']:
+                if self.hq_feat_loss: # codebook loss 
+                    l_feat_encoder = torch.mean((quant_feat_gt.detach()-lq_feat)**2) * self.feat_loss_weight
+                    l_g_total += l_feat_encoder
+                    loss_dict['l_feat_encoder'] = l_feat_encoder
+
+                # cross_entropy_loss
+                if self.cross_entropy_loss:
+                    # b(hw)n -> bn(hw)
+                    cross_entropy_loss = F.cross_entropy(logits.permute(0, 2, 1), self.idx_gt) * self.entropy_loss_weight
+                    l_g_total += cross_entropy_loss
+                    loss_dict['cross_entropy_loss'] = cross_entropy_loss
+
+            # pixel loss 
+            if not large_de: # when large degradation don't need image-level loss
+                if self.cri_pix:
+                    l_g_pix = self.cri_pix(self.output, self.gt)
+                    l_g_total += l_g_pix
+                    loss_dict['l_g_pix'] = l_g_pix
+
+                # perceptual loss
+                if self.cri_perceptual:
+                    l_g_percep = self.cri_perceptual(self.output, self.gt)
+                    l_g_total += l_g_percep
+                    loss_dict['l_g_percep'] = l_g_percep
+
+                # gan loss
+                if  current_iter > self.net_d_start_iter:
+                    fake_g_pred = self.net_d(self.output)
+                    l_g_gan = self.cri_gan(fake_g_pred, True, is_disc=False)
+                    recon_loss = l_g_pix + l_g_percep
+                    if not self.fix_generator:
+                        last_layer = self.net_g.module.generator.blocks[-1].weight
+                        d_weight = self.calculate_adaptive_weight(recon_loss, l_g_gan, last_layer, disc_weight_max=1.0)
+                    else:
+                        largest_fuse_size = self.opt['network_g']['connect_list'][-1]
+                        last_layer = self.net_g.module.fuse_convs_dict[largest_fuse_size].shift[-1].weight
+                        d_weight = self.calculate_adaptive_weight(recon_loss, l_g_gan, last_layer, disc_weight_max=1.0)
+                    
+                    d_weight *= self.scale_adaptive_gan_weight # 0.8
+                    loss_dict['d_weight'] = d_weight
+                    l_g_total += d_weight * l_g_gan
+                    loss_dict['l_g_gan'] = d_weight * l_g_gan
+
+            l_g_total.backward()
+            self.optimizer_g.step()
+
+        if self.ema_decay > 0:
+            self.model_ema(decay=self.ema_decay)
+
+        # optimize net_d
+        if not large_de:
+            if current_iter > self.net_d_start_iter:
+                for p in self.net_d.parameters():
+                    p.requires_grad = True
+
+                self.optimizer_d.zero_grad()
+                # real
+                real_d_pred = self.net_d(self.gt)
+                l_d_real = self.cri_gan(real_d_pred, True, is_disc=True)
+                loss_dict['l_d_real'] = l_d_real
+                loss_dict['out_d_real'] = torch.mean(real_d_pred.detach())
+                l_d_real.backward()
+                # fake
+                fake_d_pred = self.net_d(self.output.detach())
+                l_d_fake = self.cri_gan(fake_d_pred, False, is_disc=True)
+                loss_dict['l_d_fake'] = l_d_fake
+                loss_dict['out_d_fake'] = torch.mean(fake_d_pred.detach())
+                l_d_fake.backward()
+
+                self.optimizer_d.step()
+
+        self.log_dict = self.reduce_loss_dict(loss_dict)
+
+
+    def test(self):
+        with torch.no_grad():
+            if hasattr(self, 'net_g_ema'):
+                self.net_g_ema.eval()
+                self.output, _, _ = self.net_g_ema(self.input, w=1)
+            else:
+                logger = get_root_logger()
+                logger.warning('Do not have self.net_g_ema, use self.net_g.')
+                self.net_g.eval()
+                self.output, _, _ = self.net_g(self.input, w=1)
+                self.net_g.train()
+
+
+    def dist_validation(self, dataloader, current_iter, tb_logger, save_img):
+        if self.opt['rank'] == 0:
+            self.nondist_validation(dataloader, current_iter, tb_logger, save_img)
+
+
+    def nondist_validation(self, dataloader, current_iter, tb_logger, save_img):
+        dataset_name = dataloader.dataset.opt['name']
+        with_metrics = self.opt['val'].get('metrics') is not None
+        if with_metrics:
+            self.metric_results = {metric: 0 for metric in self.opt['val']['metrics'].keys()}
+        pbar = tqdm(total=len(dataloader), unit='image')
+
+        for idx, val_data in enumerate(dataloader):
+            img_name = osp.splitext(osp.basename(val_data['lq_path'][0]))[0]
+            self.feed_data(val_data)
+            self.test()
+
+            visuals = self.get_current_visuals()
+            sr_img = tensor2img([visuals['result']])
+            if 'gt' in visuals:
+                gt_img = tensor2img([visuals['gt']])
+                del self.gt
+
+            # tentative for out of GPU memory
+            del self.lq
+            del self.output
+            torch.cuda.empty_cache()
+
+            if save_img:
+                if self.opt['is_train']:
+                    save_img_path = osp.join(self.opt['path']['visualization'], img_name,
+                                             f'{img_name}_{current_iter}.png')
+                else:
+                    if self.opt['val']['suffix']:
+                        save_img_path = osp.join(self.opt['path']['visualization'], dataset_name,
+                                                 f'{img_name}_{self.opt["val"]["suffix"]}.png')
+                    else:
+                        save_img_path = osp.join(self.opt['path']['visualization'], dataset_name,
+                                                 f'{img_name}_{self.opt["name"]}.png')
+                imwrite(sr_img, save_img_path)
+
+            if with_metrics:
+                # calculate metrics
+                for name, opt_ in self.opt['val']['metrics'].items():
+                    metric_data = dict(img1=sr_img, img2=gt_img)
+                    self.metric_results[name] += calculate_metric(metric_data, opt_)
+            pbar.update(1)
+            pbar.set_description(f'Test {img_name}')
+        pbar.close()
+
+        if with_metrics:
+            for metric in self.metric_results.keys():
+                self.metric_results[metric] /= (idx + 1)
+
+            self._log_validation_metric_values(current_iter, dataset_name, tb_logger)
+
+
+    def _log_validation_metric_values(self, current_iter, dataset_name, tb_logger):
+        log_str = f'Validation {dataset_name}\n'
+        for metric, value in self.metric_results.items():
+            log_str += f'\t # {metric}: {value:.4f}\n'
+        logger = get_root_logger()
+        logger.info(log_str)
+        if tb_logger:
+            for metric, value in self.metric_results.items():
+                tb_logger.add_scalar(f'metrics/{metric}', value, current_iter)
+
+
+    def get_current_visuals(self):
+        out_dict = OrderedDict()
+        out_dict['gt'] = self.gt.detach().cpu()
+        out_dict['result'] = self.output.detach().cpu()
+        return out_dict
+
+
+    def save(self, epoch, current_iter):
+        if self.ema_decay > 0:
+            self.save_network([self.net_g, self.net_g_ema], 'net_g', current_iter, param_key=['params', 'params_ema'])
+        else:
+            self.save_network(self.net_g, 'net_g', current_iter)
+        self.save_network(self.net_d, 'net_d', current_iter)
+        self.save_training_state(epoch, current_iter)

basicsr/models/codeformer_model.py

@@ -0,0 +1,332 @@
+import torch
+from collections import OrderedDict
+from os import path as osp
+from tqdm import tqdm
+
+from basicsr.archs import build_network
+from basicsr.losses import build_loss
+from basicsr.metrics import calculate_metric
+from basicsr.utils import get_root_logger, imwrite, tensor2img
+from basicsr.utils.registry import MODEL_REGISTRY
+import torch.nn.functional as F
+from .sr_model import SRModel
+
+
+@MODEL_REGISTRY.register()
+class CodeFormerModel(SRModel):
+    def feed_data(self, data):
+        self.gt = data['gt'].to(self.device)
+        self.input = data['in'].to(self.device)
+        self.b = self.gt.shape[0]
+
+        if 'latent_gt' in data:
+            self.idx_gt = data['latent_gt'].to(self.device)
+            self.idx_gt = self.idx_gt.view(self.b, -1)
+        else:
+            self.idx_gt = None
+
+    def init_training_settings(self):
+        logger = get_root_logger()
+        train_opt = self.opt['train']
+
+        self.ema_decay = train_opt.get('ema_decay', 0)
+        if self.ema_decay > 0:
+            logger.info(f'Use Exponential Moving Average with decay: {self.ema_decay}')
+            # define network net_g with Exponential Moving Average (EMA)
+            # net_g_ema is used only for testing on one GPU and saving
+            # There is no need to wrap with DistributedDataParallel
+            self.net_g_ema = build_network(self.opt['network_g']).to(self.device)
+            # load pretrained model
+            load_path = self.opt['path'].get('pretrain_network_g', None)
+            if load_path is not None:
+                self.load_network(self.net_g_ema, load_path, self.opt['path'].get('strict_load_g', True), 'params_ema')
+            else:
+                self.model_ema(0)  # copy net_g weight
+            self.net_g_ema.eval()
+
+        if self.opt.get('network_vqgan', None) is not None and self.opt['datasets'].get('latent_gt_path') is None:
+            self.hq_vqgan_fix = build_network(self.opt['network_vqgan']).to(self.device)
+            self.hq_vqgan_fix.eval()
+            self.generate_idx_gt = True
+            for param in self.hq_vqgan_fix.parameters():
+                param.requires_grad = False
+        else:
+            self.generate_idx_gt = False
+
+        self.hq_feat_loss = train_opt.get('use_hq_feat_loss', True)
+        self.feat_loss_weight = train_opt.get('feat_loss_weight', 1.0)
+        self.cross_entropy_loss = train_opt.get('cross_entropy_loss', True)
+        self.entropy_loss_weight = train_opt.get('entropy_loss_weight', 0.5)
+        self.fidelity_weight = train_opt.get('fidelity_weight', 1.0)
+        self.scale_adaptive_gan_weight = train_opt.get('scale_adaptive_gan_weight', 0.8)
+
+
+        self.net_g.train()
+        # define network net_d
+        if self.fidelity_weight > 0:
+            self.net_d = build_network(self.opt['network_d'])
+            self.net_d = self.model_to_device(self.net_d)
+            self.print_network(self.net_d)
+
+            # load pretrained models
+            load_path = self.opt['path'].get('pretrain_network_d', None)
+            if load_path is not None:
+                self.load_network(self.net_d, load_path, self.opt['path'].get('strict_load_d', True))
+
+            self.net_d.train()
+
+        # define losses
+        if train_opt.get('pixel_opt'):
+            self.cri_pix = build_loss(train_opt['pixel_opt']).to(self.device)
+        else:
+            self.cri_pix = None
+
+        if train_opt.get('perceptual_opt'):
+            self.cri_perceptual = build_loss(train_opt['perceptual_opt']).to(self.device)
+        else:
+            self.cri_perceptual = None
+
+        if train_opt.get('gan_opt'):
+            self.cri_gan = build_loss(train_opt['gan_opt']).to(self.device)
+
+
+        self.fix_generator = train_opt.get('fix_generator', True)
+        logger.info(f'fix_generator: {self.fix_generator}')
+
+        self.net_g_start_iter = train_opt.get('net_g_start_iter', 0)
+        self.net_d_iters = train_opt.get('net_d_iters', 1)
+        self.net_d_start_iter = train_opt.get('net_d_start_iter', 0)
+
+        # set up optimizers and schedulers
+        self.setup_optimizers()
+        self.setup_schedulers()
+
+    def calculate_adaptive_weight(self, recon_loss, g_loss, last_layer, disc_weight_max):
+        recon_grads = torch.autograd.grad(recon_loss, last_layer, retain_graph=True)[0]
+        g_grads = torch.autograd.grad(g_loss, last_layer, retain_graph=True)[0]
+
+        d_weight = torch.norm(recon_grads) / (torch.norm(g_grads) + 1e-4)
+        d_weight = torch.clamp(d_weight, 0.0, disc_weight_max).detach()
+        return d_weight
+
+    def setup_optimizers(self):
+        train_opt = self.opt['train']
+        # optimizer g
+        optim_params_g = []
+        for k, v in self.net_g.named_parameters():
+            if v.requires_grad:
+                optim_params_g.append(v)
+            else:
+                logger = get_root_logger()
+                logger.warning(f'Params {k} will not be optimized.')
+        optim_type = train_opt['optim_g'].pop('type')
+        self.optimizer_g = self.get_optimizer(optim_type, optim_params_g, **train_opt['optim_g'])
+        self.optimizers.append(self.optimizer_g)
+        # optimizer d
+        if self.fidelity_weight > 0:
+            optim_type = train_opt['optim_d'].pop('type')
+            self.optimizer_d = self.get_optimizer(optim_type, self.net_d.parameters(), **train_opt['optim_d'])
+            self.optimizers.append(self.optimizer_d)
+
+    def gray_resize_for_identity(self, out, size=128):
+        out_gray = (0.2989 * out[:, 0, :, :] + 0.5870 * out[:, 1, :, :] + 0.1140 * out[:, 2, :, :])
+        out_gray = out_gray.unsqueeze(1)
+        out_gray = F.interpolate(out_gray, (size, size), mode='bilinear', align_corners=False)
+        return out_gray
+
+    def optimize_parameters(self, current_iter):
+        logger = get_root_logger()
+        # optimize net_g
+        for p in self.net_d.parameters():
+            p.requires_grad = False
+
+        self.optimizer_g.zero_grad()
+
+        if self.generate_idx_gt:
+            x = self.hq_vqgan_fix.encoder(self.gt)
+            output, _, quant_stats = self.hq_vqgan_fix.quantize(x)
+            min_encoding_indices = quant_stats['min_encoding_indices']
+            self.idx_gt = min_encoding_indices.view(self.b, -1)
+
+        if self.fidelity_weight > 0:
+            self.output, logits, lq_feat = self.net_g(self.input, w=self.fidelity_weight, detach_16=True)
+        else:
+            logits, lq_feat = self.net_g(self.input, w=0, code_only=True)
+
+        if self.hq_feat_loss:
+            # quant_feats
+            quant_feat_gt = self.net_g.module.quantize.get_codebook_feat(self.idx_gt, shape=[self.b,16,16,256])
+
+        l_g_total = 0
+        loss_dict = OrderedDict()
+        if current_iter % self.net_d_iters == 0 and current_iter > self.net_g_start_iter:
+            # hq_feat_loss
+            if self.hq_feat_loss: # codebook loss 
+                l_feat_encoder = torch.mean((quant_feat_gt.detach()-lq_feat)**2) * self.feat_loss_weight
+                l_g_total += l_feat_encoder
+                loss_dict['l_feat_encoder'] = l_feat_encoder
+
+            # cross_entropy_loss
+            if self.cross_entropy_loss:
+                # b(hw)n -> bn(hw)
+                cross_entropy_loss = F.cross_entropy(logits.permute(0, 2, 1), self.idx_gt) * self.entropy_loss_weight
+                l_g_total += cross_entropy_loss
+                loss_dict['cross_entropy_loss'] = cross_entropy_loss
+
+            if self.fidelity_weight > 0: # when fidelity_weight == 0 don't need image-level loss
+                # pixel loss
+                if self.cri_pix:
+                    l_g_pix = self.cri_pix(self.output, self.gt)
+                    l_g_total += l_g_pix
+                    loss_dict['l_g_pix'] = l_g_pix
+
+                # perceptual loss
+                if self.cri_perceptual:
+                    l_g_percep = self.cri_perceptual(self.output, self.gt)
+                    l_g_total += l_g_percep
+                    loss_dict['l_g_percep'] = l_g_percep
+
+                # gan loss
+                if  current_iter > self.net_d_start_iter:
+                    fake_g_pred = self.net_d(self.output)
+                    l_g_gan = self.cri_gan(fake_g_pred, True, is_disc=False)
+                    recon_loss = l_g_pix + l_g_percep
+                    if not self.fix_generator:
+                        last_layer = self.net_g.module.generator.blocks[-1].weight
+                        d_weight = self.calculate_adaptive_weight(recon_loss, l_g_gan, last_layer, disc_weight_max=1.0)
+                    else:
+                        largest_fuse_size = self.opt['network_g']['connect_list'][-1]
+                        last_layer = self.net_g.module.fuse_convs_dict[largest_fuse_size].shift[-1].weight
+                        d_weight = self.calculate_adaptive_weight(recon_loss, l_g_gan, last_layer, disc_weight_max=1.0)
+                    
+                    d_weight *= self.scale_adaptive_gan_weight # 0.8
+                    loss_dict['d_weight'] = d_weight
+                    l_g_total += d_weight * l_g_gan
+                    loss_dict['l_g_gan'] = d_weight * l_g_gan
+
+            l_g_total.backward()
+            self.optimizer_g.step()
+
+        if self.ema_decay > 0:
+            self.model_ema(decay=self.ema_decay)
+
+        # optimize net_d
+        if  current_iter > self.net_d_start_iter and self.fidelity_weight > 0:
+            for p in self.net_d.parameters():
+                p.requires_grad = True
+
+            self.optimizer_d.zero_grad()
+            # real
+            real_d_pred = self.net_d(self.gt)
+            l_d_real = self.cri_gan(real_d_pred, True, is_disc=True)
+            loss_dict['l_d_real'] = l_d_real
+            loss_dict['out_d_real'] = torch.mean(real_d_pred.detach())
+            l_d_real.backward()
+            # fake
+            fake_d_pred = self.net_d(self.output.detach())
+            l_d_fake = self.cri_gan(fake_d_pred, False, is_disc=True)
+            loss_dict['l_d_fake'] = l_d_fake
+            loss_dict['out_d_fake'] = torch.mean(fake_d_pred.detach())
+            l_d_fake.backward()
+
+            self.optimizer_d.step()
+
+        self.log_dict = self.reduce_loss_dict(loss_dict)
+
+
+    def test(self):
+        with torch.no_grad():
+            if hasattr(self, 'net_g_ema'):
+                self.net_g_ema.eval()
+                self.output, _, _ = self.net_g_ema(self.input, w=self.fidelity_weight)
+            else:
+                logger = get_root_logger()
+                logger.warning('Do not have self.net_g_ema, use self.net_g.')
+                self.net_g.eval()
+                self.output, _, _ = self.net_g(self.input, w=self.fidelity_weight)
+                self.net_g.train()
+
+
+    def dist_validation(self, dataloader, current_iter, tb_logger, save_img):
+        if self.opt['rank'] == 0:
+            self.nondist_validation(dataloader, current_iter, tb_logger, save_img)
+
+
+    def nondist_validation(self, dataloader, current_iter, tb_logger, save_img):
+        dataset_name = dataloader.dataset.opt['name']
+        with_metrics = self.opt['val'].get('metrics') is not None
+        if with_metrics:
+            self.metric_results = {metric: 0 for metric in self.opt['val']['metrics'].keys()}
+        pbar = tqdm(total=len(dataloader), unit='image')
+
+        for idx, val_data in enumerate(dataloader):
+            img_name = osp.splitext(osp.basename(val_data['lq_path'][0]))[0]
+            self.feed_data(val_data)
+            self.test()
+
+            visuals = self.get_current_visuals()
+            sr_img = tensor2img([visuals['result']])
+            if 'gt' in visuals:
+                gt_img = tensor2img([visuals['gt']])
+                del self.gt
+
+            # tentative for out of GPU memory
+            del self.lq
+            del self.output
+            torch.cuda.empty_cache()
+
+            if save_img:
+                if self.opt['is_train']:
+                    save_img_path = osp.join(self.opt['path']['visualization'], img_name,
+                                             f'{img_name}_{current_iter}.png')
+                else:
+                    if self.opt['val']['suffix']:
+                        save_img_path = osp.join(self.opt['path']['visualization'], dataset_name,
+                                                 f'{img_name}_{self.opt["val"]["suffix"]}.png')
+                    else:
+                        save_img_path = osp.join(self.opt['path']['visualization'], dataset_name,
+                                                 f'{img_name}_{self.opt["name"]}.png')
+                imwrite(sr_img, save_img_path)
+
+            if with_metrics:
+                # calculate metrics
+                for name, opt_ in self.opt['val']['metrics'].items():
+                    metric_data = dict(img1=sr_img, img2=gt_img)
+                    self.metric_results[name] += calculate_metric(metric_data, opt_)
+            pbar.update(1)
+            pbar.set_description(f'Test {img_name}')
+        pbar.close()
+
+        if with_metrics:
+            for metric in self.metric_results.keys():
+                self.metric_results[metric] /= (idx + 1)
+
+            self._log_validation_metric_values(current_iter, dataset_name, tb_logger)
+
+
+    def _log_validation_metric_values(self, current_iter, dataset_name, tb_logger):
+        log_str = f'Validation {dataset_name}\n'
+        for metric, value in self.metric_results.items():
+            log_str += f'\t # {metric}: {value:.4f}\n'
+        logger = get_root_logger()
+        logger.info(log_str)
+        if tb_logger:
+            for metric, value in self.metric_results.items():
+                tb_logger.add_scalar(f'metrics/{metric}', value, current_iter)
+
+
+    def get_current_visuals(self):
+        out_dict = OrderedDict()
+        out_dict['gt'] = self.gt.detach().cpu()
+        out_dict['result'] = self.output.detach().cpu()
+        return out_dict
+
+
+    def save(self, epoch, current_iter):
+        if self.ema_decay > 0:
+            self.save_network([self.net_g, self.net_g_ema], 'net_g', current_iter, param_key=['params', 'params_ema'])
+        else:
+            self.save_network(self.net_g, 'net_g', current_iter)
+        if self.fidelity_weight > 0:
+            self.save_network(self.net_d, 'net_d', current_iter)
+        self.save_training_state(epoch, current_iter)

basicsr/models/lr_scheduler.py

@@ -0,0 +1,96 @@
+import math
+from collections import Counter
+from torch.optim.lr_scheduler import _LRScheduler
+
+
+class MultiStepRestartLR(_LRScheduler):
+    """ MultiStep with restarts learning rate scheme.
+
+    Args:
+        optimizer (torch.nn.optimizer): Torch optimizer.
+        milestones (list): Iterations that will decrease learning rate.
+        gamma (float): Decrease ratio. Default: 0.1.
+        restarts (list): Restart iterations. Default: [0].
+        restart_weights (list): Restart weights at each restart iteration.
+            Default: [1].
+        last_epoch (int): Used in _LRScheduler. Default: -1.
+    """
+
+    def __init__(self, optimizer, milestones, gamma=0.1, restarts=(0, ), restart_weights=(1, ), last_epoch=-1):
+        self.milestones = Counter(milestones)
+        self.gamma = gamma
+        self.restarts = restarts
+        self.restart_weights = restart_weights
+        assert len(self.restarts) == len(self.restart_weights), 'restarts and their weights do not match.'
+        super(MultiStepRestartLR, self).__init__(optimizer, last_epoch)
+
+    def get_lr(self):
+        if self.last_epoch in self.restarts:
+            weight = self.restart_weights[self.restarts.index(self.last_epoch)]
+            return [group['initial_lr'] * weight for group in self.optimizer.param_groups]
+        if self.last_epoch not in self.milestones:
+            return [group['lr'] for group in self.optimizer.param_groups]
+        return [group['lr'] * self.gamma**self.milestones[self.last_epoch] for group in self.optimizer.param_groups]
+
+
+def get_position_from_periods(iteration, cumulative_period):
+    """Get the position from a period list.
+
+    It will return the index of the right-closest number in the period list.
+    For example, the cumulative_period = [100, 200, 300, 400],
+    if iteration == 50, return 0;
+    if iteration == 210, return 2;
+    if iteration == 300, return 2.
+
+    Args:
+        iteration (int): Current iteration.
+        cumulative_period (list[int]): Cumulative period list.
+
+    Returns:
+        int: The position of the right-closest number in the period list.
+    """
+    for i, period in enumerate(cumulative_period):
+        if iteration <= period:
+            return i
+
+
+class CosineAnnealingRestartLR(_LRScheduler):
+    """ Cosine annealing with restarts learning rate scheme.
+
+    An example of config:
+    periods = [10, 10, 10, 10]
+    restart_weights = [1, 0.5, 0.5, 0.5]
+    eta_min=1e-7
+
+    It has four cycles, each has 10 iterations. At 10th, 20th, 30th, the
+    scheduler will restart with the weights in restart_weights.
+
+    Args:
+        optimizer (torch.nn.optimizer): Torch optimizer.
+        periods (list): Period for each cosine anneling cycle.
+        restart_weights (list): Restart weights at each restart iteration.
+            Default: [1].
+        eta_min (float): The mimimum lr. Default: 0.
+        last_epoch (int): Used in _LRScheduler. Default: -1.
+    """
+
+    def __init__(self, optimizer, periods, restart_weights=(1, ), eta_min=0, last_epoch=-1):
+        self.periods = periods
+        self.restart_weights = restart_weights
+        self.eta_min = eta_min
+        assert (len(self.periods) == len(
+            self.restart_weights)), 'periods and restart_weights should have the same length.'
+        self.cumulative_period = [sum(self.periods[0:i + 1]) for i in range(0, len(self.periods))]
+        super(CosineAnnealingRestartLR, self).__init__(optimizer, last_epoch)
+
+    def get_lr(self):
+        idx = get_position_from_periods(self.last_epoch, self.cumulative_period)
+        current_weight = self.restart_weights[idx]
+        nearest_restart = 0 if idx == 0 else self.cumulative_period[idx - 1]
+        current_period = self.periods[idx]
+
+        return [
+            self.eta_min + current_weight * 0.5 * (base_lr - self.eta_min) *
+            (1 + math.cos(math.pi * ((self.last_epoch - nearest_restart) / current_period)))
+            for base_lr in self.base_lrs
+        ]

basicsr/models/sr_model.py

@@ -0,0 +1,209 @@
+import torch
+from collections import OrderedDict
+from os import path as osp
+from tqdm import tqdm
+
+from basicsr.archs import build_network
+from basicsr.losses import build_loss
+from basicsr.metrics import calculate_metric
+from basicsr.utils import get_root_logger, imwrite, tensor2img
+from basicsr.utils.registry import MODEL_REGISTRY
+from .base_model import BaseModel
+
+@MODEL_REGISTRY.register()
+class SRModel(BaseModel):
+    """Base SR model for single image super-resolution."""
+
+    def __init__(self, opt):
+        super(SRModel, self).__init__(opt)
+
+        # define network
+        self.net_g = build_network(opt['network_g'])
+        self.net_g = self.model_to_device(self.net_g)
+        self.print_network(self.net_g)
+
+        # load pretrained models
+        load_path = self.opt['path'].get('pretrain_network_g', None)
+        if load_path is not None:
+            param_key = self.opt['path'].get('param_key_g', 'params')
+            self.load_network(self.net_g, load_path, self.opt['path'].get('strict_load_g', True), param_key)
+
+        if self.is_train:
+            self.init_training_settings()
+
+    def init_training_settings(self):
+        self.net_g.train()
+        train_opt = self.opt['train']
+
+        self.ema_decay = train_opt.get('ema_decay', 0)
+        if self.ema_decay > 0:
+            logger = get_root_logger()
+            logger.info(f'Use Exponential Moving Average with decay: {self.ema_decay}')
+            # define network net_g with Exponential Moving Average (EMA)
+            # net_g_ema is used only for testing on one GPU and saving
+            # There is no need to wrap with DistributedDataParallel
+            self.net_g_ema = build_network(self.opt['network_g']).to(self.device)
+            # load pretrained model
+            load_path = self.opt['path'].get('pretrain_network_g', None)
+            if load_path is not None:
+                self.load_network(self.net_g_ema, load_path, self.opt['path'].get('strict_load_g', True), 'params_ema')
+            else:
+                self.model_ema(0)  # copy net_g weight
+            self.net_g_ema.eval()
+
+        # define losses
+        if train_opt.get('pixel_opt'):
+            self.cri_pix = build_loss(train_opt['pixel_opt']).to(self.device)
+        else:
+            self.cri_pix = None
+
+        if train_opt.get('perceptual_opt'):
+            self.cri_perceptual = build_loss(train_opt['perceptual_opt']).to(self.device)
+        else:
+            self.cri_perceptual = None
+
+        if self.cri_pix is None and self.cri_perceptual is None:
+            raise ValueError('Both pixel and perceptual losses are None.')
+
+        # set up optimizers and schedulers
+        self.setup_optimizers()
+        self.setup_schedulers()
+
+    def setup_optimizers(self):
+        train_opt = self.opt['train']
+        optim_params = []
+        for k, v in self.net_g.named_parameters():
+            if v.requires_grad:
+                optim_params.append(v)
+            else:
+                logger = get_root_logger()
+                logger.warning(f'Params {k} will not be optimized.')
+
+        optim_type = train_opt['optim_g'].pop('type')
+        self.optimizer_g = self.get_optimizer(optim_type, optim_params, **train_opt['optim_g'])
+        self.optimizers.append(self.optimizer_g)
+
+    def feed_data(self, data):
+        self.lq = data['lq'].to(self.device)
+        if 'gt' in data:
+            self.gt = data['gt'].to(self.device)
+
+    def optimize_parameters(self, current_iter):
+        self.optimizer_g.zero_grad()
+        self.output = self.net_g(self.lq)
+
+        l_total = 0
+        loss_dict = OrderedDict()
+        # pixel loss
+        if self.cri_pix:
+            l_pix = self.cri_pix(self.output, self.gt)
+            l_total += l_pix
+            loss_dict['l_pix'] = l_pix
+        # perceptual loss
+        if self.cri_perceptual:
+            l_percep, l_style = self.cri_perceptual(self.output, self.gt)
+            if l_percep is not None:
+                l_total += l_percep
+                loss_dict['l_percep'] = l_percep
+            if l_style is not None:
+                l_total += l_style
+                loss_dict['l_style'] = l_style
+
+        l_total.backward()
+        self.optimizer_g.step()
+
+        self.log_dict = self.reduce_loss_dict(loss_dict)
+
+        if self.ema_decay > 0:
+            self.model_ema(decay=self.ema_decay)
+
+    def test(self):
+        if hasattr(self, 'ema_decay'):
+            self.net_g_ema.eval()
+            with torch.no_grad():
+                self.output = self.net_g_ema(self.lq)
+        else:
+            self.net_g.eval()
+            with torch.no_grad():
+                self.output = self.net_g(self.lq)
+            self.net_g.train()
+
+    def dist_validation(self, dataloader, current_iter, tb_logger, save_img):
+        if self.opt['rank'] == 0:
+            self.nondist_validation(dataloader, current_iter, tb_logger, save_img)
+
+    def nondist_validation(self, dataloader, current_iter, tb_logger, save_img):
+        dataset_name = dataloader.dataset.opt['name']
+        with_metrics = self.opt['val'].get('metrics') is not None
+        if with_metrics:
+            self.metric_results = {metric: 0 for metric in self.opt['val']['metrics'].keys()}
+        pbar = tqdm(total=len(dataloader), unit='image')
+
+        for idx, val_data in enumerate(dataloader):
+            img_name = osp.splitext(osp.basename(val_data['lq_path'][0]))[0]
+            self.feed_data(val_data)
+            self.test()
+
+            visuals = self.get_current_visuals()
+            sr_img = tensor2img([visuals['result']])
+            if 'gt' in visuals:
+                gt_img = tensor2img([visuals['gt']])
+                del self.gt
+
+            # tentative for out of GPU memory
+            del self.lq
+            del self.output
+            torch.cuda.empty_cache()
+
+            if save_img:
+                if self.opt['is_train']:
+                    save_img_path = osp.join(self.opt['path']['visualization'], img_name,
+                                             f'{img_name}_{current_iter}.png')
+                else:
+                    if self.opt['val']['suffix']:
+                        save_img_path = osp.join(self.opt['path']['visualization'], dataset_name,
+                                                 f'{img_name}_{self.opt["val"]["suffix"]}.png')
+                    else:
+                        save_img_path = osp.join(self.opt['path']['visualization'], dataset_name,
+                                                 f'{img_name}_{self.opt["name"]}.png')
+                imwrite(sr_img, save_img_path)
+
+            if with_metrics:
+                # calculate metrics
+                for name, opt_ in self.opt['val']['metrics'].items():
+                    metric_data = dict(img1=sr_img, img2=gt_img)
+                    self.metric_results[name] += calculate_metric(metric_data, opt_)
+            pbar.update(1)
+            pbar.set_description(f'Test {img_name}')
+        pbar.close()
+
+        if with_metrics:
+            for metric in self.metric_results.keys():
+                self.metric_results[metric] /= (idx + 1)
+
+            self._log_validation_metric_values(current_iter, dataset_name, tb_logger)
+
+    def _log_validation_metric_values(self, current_iter, dataset_name, tb_logger):
+        log_str = f'Validation {dataset_name}\n'
+        for metric, value in self.metric_results.items():
+            log_str += f'\t # {metric}: {value:.4f}\n'
+        logger = get_root_logger()
+        logger.info(log_str)
+        if tb_logger:
+            for metric, value in self.metric_results.items():
+                tb_logger.add_scalar(f'metrics/{metric}', value, current_iter)
+
+    def get_current_visuals(self):
+        out_dict = OrderedDict()
+        out_dict['lq'] = self.lq.detach().cpu()
+        out_dict['result'] = self.output.detach().cpu()
+        if hasattr(self, 'gt'):
+            out_dict['gt'] = self.gt.detach().cpu()
+        return out_dict
+
+    def save(self, epoch, current_iter):
+        if hasattr(self, 'ema_decay'):
+            self.save_network([self.net_g, self.net_g_ema], 'net_g', current_iter, param_key=['params', 'params_ema'])
+        else:
+            self.save_network(self.net_g, 'net_g', current_iter)
+        self.save_training_state(epoch, current_iter)

basicsr/models/vqgan_model.py

@@ -0,0 +1,285 @@
+import torch
+from collections import OrderedDict
+from os import path as osp
+from tqdm import tqdm
+
+from basicsr.archs import build_network
+from basicsr.losses import build_loss
+from basicsr.metrics import calculate_metric
+from basicsr.utils import get_root_logger, imwrite, tensor2img
+from basicsr.utils.registry import MODEL_REGISTRY
+import torch.nn.functional as F
+from .sr_model import SRModel
+
+
+@MODEL_REGISTRY.register()
+class VQGANModel(SRModel):
+    def feed_data(self, data):
+        self.gt = data['gt'].to(self.device)
+        self.b = self.gt.shape[0]
+
+
+    def init_training_settings(self):
+        logger = get_root_logger()
+        train_opt = self.opt['train']
+
+        self.ema_decay = train_opt.get('ema_decay', 0)
+        if self.ema_decay > 0:
+            logger.info(f'Use Exponential Moving Average with decay: {self.ema_decay}')
+            # define network net_g with Exponential Moving Average (EMA)
+            # net_g_ema is used only for testing on one GPU and saving
+            # There is no need to wrap with DistributedDataParallel
+            self.net_g_ema = build_network(self.opt['network_g']).to(self.device)
+            # load pretrained model
+            load_path = self.opt['path'].get('pretrain_network_g', None)
+            if load_path is not None:
+                self.load_network(self.net_g_ema, load_path, self.opt['path'].get('strict_load_g', True), 'params_ema')
+            else:
+                self.model_ema(0)  # copy net_g weight
+            self.net_g_ema.eval()
+
+        # define network net_d
+        self.net_d = build_network(self.opt['network_d'])
+        self.net_d = self.model_to_device(self.net_d)
+        self.print_network(self.net_d)
+
+        # load pretrained models
+        load_path = self.opt['path'].get('pretrain_network_d', None)
+        if load_path is not None:
+            self.load_network(self.net_d, load_path, self.opt['path'].get('strict_load_d', True))
+
+        self.net_g.train()
+        self.net_d.train()
+
+        # define losses
+        if train_opt.get('pixel_opt'):
+            self.cri_pix = build_loss(train_opt['pixel_opt']).to(self.device)
+        else:
+            self.cri_pix = None
+
+        if train_opt.get('perceptual_opt'):
+            self.cri_perceptual = build_loss(train_opt['perceptual_opt']).to(self.device)
+        else:
+            self.cri_perceptual = None
+
+        if train_opt.get('gan_opt'):
+            self.cri_gan = build_loss(train_opt['gan_opt']).to(self.device)
+
+        if train_opt.get('codebook_opt'):
+            self.l_weight_codebook = train_opt['codebook_opt'].get('loss_weight', 1.0)
+        else:
+            self.l_weight_codebook = 1.0
+        
+        self.vqgan_quantizer = self.opt['network_g']['quantizer']
+        logger.info(f'vqgan_quantizer: {self.vqgan_quantizer}')
+
+        self.net_g_start_iter = train_opt.get('net_g_start_iter', 0)
+        self.net_d_iters = train_opt.get('net_d_iters', 1)
+        self.net_d_start_iter = train_opt.get('net_d_start_iter', 0)
+        self.disc_weight = train_opt.get('disc_weight', 0.8)
+
+        # set up optimizers and schedulers
+        self.setup_optimizers()
+        self.setup_schedulers()
+
+    def calculate_adaptive_weight(self, recon_loss, g_loss, last_layer, disc_weight_max):
+        recon_grads = torch.autograd.grad(recon_loss, last_layer, retain_graph=True)[0]
+        g_grads = torch.autograd.grad(g_loss, last_layer, retain_graph=True)[0]
+
+        d_weight = torch.norm(recon_grads) / (torch.norm(g_grads) + 1e-4)
+        d_weight = torch.clamp(d_weight, 0.0, disc_weight_max).detach()
+        return d_weight
+
+    def adopt_weight(self, weight, global_step, threshold=0, value=0.):
+        if global_step < threshold:
+            weight = value
+        return weight
+
+    def setup_optimizers(self):
+        train_opt = self.opt['train']
+        # optimizer g
+        optim_params_g = []
+        for k, v in self.net_g.named_parameters():
+            if v.requires_grad:
+                optim_params_g.append(v)
+            else:
+                logger = get_root_logger()
+                logger.warning(f'Params {k} will not be optimized.')
+        optim_type = train_opt['optim_g'].pop('type')
+        self.optimizer_g = self.get_optimizer(optim_type, optim_params_g, **train_opt['optim_g'])
+        self.optimizers.append(self.optimizer_g)
+        # optimizer d
+        optim_type = train_opt['optim_d'].pop('type')
+        self.optimizer_d = self.get_optimizer(optim_type, self.net_d.parameters(), **train_opt['optim_d'])
+        self.optimizers.append(self.optimizer_d)
+
+
+    def optimize_parameters(self, current_iter):
+        logger = get_root_logger()
+        loss_dict = OrderedDict()
+        if self.opt['network_g']['quantizer'] == 'gumbel':
+            self.net_g.module.quantize.temperature = max(1/16, ((-1/160000) * current_iter) + 1)
+            if current_iter%1000 == 0:
+                logger.info(f'temperature: {self.net_g.module.quantize.temperature}')
+
+        # optimize net_g
+        for p in self.net_d.parameters():
+            p.requires_grad = False
+
+        self.optimizer_g.zero_grad()
+        self.output, l_codebook, quant_stats = self.net_g(self.gt)
+
+        l_codebook = l_codebook*self.l_weight_codebook
+
+        l_g_total = 0
+        if current_iter % self.net_d_iters == 0 and current_iter > self.net_g_start_iter:
+            # pixel loss
+            if self.cri_pix:
+                l_g_pix = self.cri_pix(self.output, self.gt)
+                l_g_total += l_g_pix
+                loss_dict['l_g_pix'] = l_g_pix
+            # perceptual loss
+            if self.cri_perceptual:
+                l_g_percep = self.cri_perceptual(self.output, self.gt)
+                l_g_total += l_g_percep
+                loss_dict['l_g_percep'] = l_g_percep
+
+            # gan loss
+            if current_iter > self.net_d_start_iter:
+                # fake_g_pred = self.net_d(self.output_1024)
+                fake_g_pred = self.net_d(self.output)
+                l_g_gan = self.cri_gan(fake_g_pred, True, is_disc=False)
+                recon_loss = l_g_total
+                last_layer = self.net_g.module.generator.blocks[-1].weight
+                d_weight = self.calculate_adaptive_weight(recon_loss, l_g_gan, last_layer, disc_weight_max=1.0)
+                d_weight *= self.adopt_weight(1, current_iter, self.net_d_start_iter)
+                d_weight *= self.disc_weight # tamming setting 0.8
+                l_g_total += d_weight * l_g_gan
+                loss_dict['l_g_gan'] = d_weight * l_g_gan
+
+            l_g_total += l_codebook
+            loss_dict['l_codebook'] = l_codebook
+
+            l_g_total.backward()
+            self.optimizer_g.step()
+
+        # optimize net_d
+        if  current_iter > self.net_d_start_iter:
+            for p in self.net_d.parameters():
+                p.requires_grad = True
+
+            self.optimizer_d.zero_grad()
+            # real
+            real_d_pred = self.net_d(self.gt)
+            l_d_real = self.cri_gan(real_d_pred, True, is_disc=True)
+            loss_dict['l_d_real'] = l_d_real
+            loss_dict['out_d_real'] = torch.mean(real_d_pred.detach())
+            l_d_real.backward()
+            # fake
+            fake_d_pred = self.net_d(self.output.detach())
+            l_d_fake = self.cri_gan(fake_d_pred, False, is_disc=True)
+            loss_dict['l_d_fake'] = l_d_fake
+            loss_dict['out_d_fake'] = torch.mean(fake_d_pred.detach())
+            l_d_fake.backward()
+            self.optimizer_d.step()
+
+        self.log_dict = self.reduce_loss_dict(loss_dict)
+
+        if self.ema_decay > 0:
+            self.model_ema(decay=self.ema_decay)
+
+
+    def test(self):
+        with torch.no_grad():
+            if hasattr(self, 'net_g_ema'):
+                self.net_g_ema.eval()
+                self.output, _, _ = self.net_g_ema(self.gt)
+            else:
+                logger = get_root_logger()
+                logger.warning('Do not have self.net_g_ema, use self.net_g.')
+                self.net_g.eval()
+                self.output, _, _ = self.net_g(self.gt)
+                self.net_g.train()
+
+
+    def dist_validation(self, dataloader, current_iter, tb_logger, save_img):
+        if self.opt['rank'] == 0:
+            self.nondist_validation(dataloader, current_iter, tb_logger, save_img)
+
+
+    def nondist_validation(self, dataloader, current_iter, tb_logger, save_img):
+        dataset_name = dataloader.dataset.opt['name']
+        with_metrics = self.opt['val'].get('metrics') is not None
+        if with_metrics:
+            self.metric_results = {metric: 0 for metric in self.opt['val']['metrics'].keys()}
+        pbar = tqdm(total=len(dataloader), unit='image')
+
+        for idx, val_data in enumerate(dataloader):
+            img_name = osp.splitext(osp.basename(val_data['lq_path'][0]))[0]
+            self.feed_data(val_data)
+            self.test()
+
+            visuals = self.get_current_visuals()
+            sr_img = tensor2img([visuals['result']])
+            if 'gt' in visuals:
+                gt_img = tensor2img([visuals['gt']])
+                del self.gt
+
+            # tentative for out of GPU memory
+            del self.lq
+            del self.output
+            torch.cuda.empty_cache()
+
+            if save_img:
+                if self.opt['is_train']:
+                    save_img_path = osp.join(self.opt['path']['visualization'], img_name,
+                                             f'{img_name}_{current_iter}.png')
+                else:
+                    if self.opt['val']['suffix']:
+                        save_img_path = osp.join(self.opt['path']['visualization'], dataset_name,
+                                                 f'{img_name}_{self.opt["val"]["suffix"]}.png')
+                    else:
+                        save_img_path = osp.join(self.opt['path']['visualization'], dataset_name,
+                                                 f'{img_name}_{self.opt["name"]}.png')
+                imwrite(sr_img, save_img_path)
+
+            if with_metrics:
+                # calculate metrics
+                for name, opt_ in self.opt['val']['metrics'].items():
+                    metric_data = dict(img1=sr_img, img2=gt_img)
+                    self.metric_results[name] += calculate_metric(metric_data, opt_)
+            pbar.update(1)
+            pbar.set_description(f'Test {img_name}')
+        pbar.close()
+
+        if with_metrics:
+            for metric in self.metric_results.keys():
+                self.metric_results[metric] /= (idx + 1)
+
+            self._log_validation_metric_values(current_iter, dataset_name, tb_logger)
+
+
+    def _log_validation_metric_values(self, current_iter, dataset_name, tb_logger):
+        log_str = f'Validation {dataset_name}\n'
+        for metric, value in self.metric_results.items():
+            log_str += f'\t # {metric}: {value:.4f}\n'
+        logger = get_root_logger()
+        logger.info(log_str)
+        if tb_logger:
+            for metric, value in self.metric_results.items():
+                tb_logger.add_scalar(f'metrics/{metric}', value, current_iter)
+
+
+    def get_current_visuals(self):
+        out_dict = OrderedDict()
+        out_dict['gt'] = self.gt.detach().cpu()
+        out_dict['result'] = self.output.detach().cpu()
+        return out_dict
+
+    def save(self, epoch, current_iter):
+        if self.ema_decay > 0:
+            self.save_network([self.net_g, self.net_g_ema], 'net_g', current_iter, param_key=['params', 'params_ema'])
+        else:
+            self.save_network(self.net_g, 'net_g', current_iter)
+        self.save_network(self.net_d, 'net_d', current_iter)
+        self.save_training_state(epoch, current_iter)

basicsr/ops/dcn/__init__.py

@@ -0,0 +1,7 @@
+from .deform_conv import (DeformConv, DeformConvPack, ModulatedDeformConv, ModulatedDeformConvPack, deform_conv,
+                          modulated_deform_conv)
+
+__all__ = [
+    'DeformConv', 'DeformConvPack', 'ModulatedDeformConv', 'ModulatedDeformConvPack', 'deform_conv',
+    'modulated_deform_conv'
+]

basicsr/ops/dcn/deform_conv.py

@@ -0,0 +1,377 @@
+import math
+import torch
+from torch import nn as nn
+from torch.autograd import Function
+from torch.autograd.function import once_differentiable
+from torch.nn import functional as F
+from torch.nn.modules.utils import _pair, _single
+
+try:
+    from . import deform_conv_ext
+except ImportError:
+    import os
+    BASICSR_JIT = os.getenv('BASICSR_JIT')
+    if BASICSR_JIT == 'True':
+        from torch.utils.cpp_extension import load
+        module_path = os.path.dirname(__file__)
+        deform_conv_ext = load(
+            'deform_conv',
+            sources=[
+                os.path.join(module_path, 'src', 'deform_conv_ext.cpp'),
+                os.path.join(module_path, 'src', 'deform_conv_cuda.cpp'),
+                os.path.join(module_path, 'src', 'deform_conv_cuda_kernel.cu'),
+            ],
+        )
+
+
+class DeformConvFunction(Function):
+
+    @staticmethod
+    def forward(ctx,
+                input,
+                offset,
+                weight,
+                stride=1,
+                padding=0,
+                dilation=1,
+                groups=1,
+                deformable_groups=1,
+                im2col_step=64):
+        if input is not None and input.dim() != 4:
+            raise ValueError(f'Expected 4D tensor as input, got {input.dim()}' 'D tensor instead.')
+        ctx.stride = _pair(stride)
+        ctx.padding = _pair(padding)
+        ctx.dilation = _pair(dilation)
+        ctx.groups = groups
+        ctx.deformable_groups = deformable_groups
+        ctx.im2col_step = im2col_step
+
+        ctx.save_for_backward(input, offset, weight)
+
+        output = input.new_empty(DeformConvFunction._output_size(input, weight, ctx.padding, ctx.dilation, ctx.stride))
+
+        ctx.bufs_ = [input.new_empty(0), input.new_empty(0)]  # columns, ones
+
+        if not input.is_cuda:
+            raise NotImplementedError
+        else:
+            cur_im2col_step = min(ctx.im2col_step, input.shape[0])
+            assert (input.shape[0] % cur_im2col_step) == 0, 'im2col step must divide batchsize'
+            deform_conv_ext.deform_conv_forward(input, weight,
+                                                offset, output, ctx.bufs_[0], ctx.bufs_[1], weight.size(3),
+                                                weight.size(2), ctx.stride[1], ctx.stride[0], ctx.padding[1],
+                                                ctx.padding[0], ctx.dilation[1], ctx.dilation[0], ctx.groups,
+                                                ctx.deformable_groups, cur_im2col_step)
+        return output
+
+    @staticmethod
+    @once_differentiable
+    def backward(ctx, grad_output):
+        input, offset, weight = ctx.saved_tensors
+
+        grad_input = grad_offset = grad_weight = None
+
+        if not grad_output.is_cuda:
+            raise NotImplementedError
+        else:
+            cur_im2col_step = min(ctx.im2col_step, input.shape[0])
+            assert (input.shape[0] % cur_im2col_step) == 0, 'im2col step must divide batchsize'
+
+            if ctx.needs_input_grad[0] or ctx.needs_input_grad[1]:
+                grad_input = torch.zeros_like(input)
+                grad_offset = torch.zeros_like(offset)
+                deform_conv_ext.deform_conv_backward_input(input, offset, grad_output, grad_input,
+                                                           grad_offset, weight, ctx.bufs_[0], weight.size(3),
+                                                           weight.size(2), ctx.stride[1], ctx.stride[0], ctx.padding[1],
+                                                           ctx.padding[0], ctx.dilation[1], ctx.dilation[0], ctx.groups,
+                                                           ctx.deformable_groups, cur_im2col_step)
+
+            if ctx.needs_input_grad[2]:
+                grad_weight = torch.zeros_like(weight)
+                deform_conv_ext.deform_conv_backward_parameters(input, offset, grad_output, grad_weight,
+                                                                ctx.bufs_[0], ctx.bufs_[1], weight.size(3),
+                                                                weight.size(2), ctx.stride[1], ctx.stride[0],
+                                                                ctx.padding[1], ctx.padding[0], ctx.dilation[1],
+                                                                ctx.dilation[0], ctx.groups, ctx.deformable_groups, 1,
+                                                                cur_im2col_step)
+
+        return (grad_input, grad_offset, grad_weight, None, None, None, None, None)
+
+    @staticmethod
+    def _output_size(input, weight, padding, dilation, stride):
+        channels = weight.size(0)
+        output_size = (input.size(0), channels)
+        for d in range(input.dim() - 2):
+            in_size = input.size(d + 2)
+            pad = padding[d]
+            kernel = dilation[d] * (weight.size(d + 2) - 1) + 1
+            stride_ = stride[d]
+            output_size += ((in_size + (2 * pad) - kernel) // stride_ + 1, )
+        if not all(map(lambda s: s > 0, output_size)):
+            raise ValueError('convolution input is too small (output would be ' f'{"x".join(map(str, output_size))})')
+        return output_size
+
+
+class ModulatedDeformConvFunction(Function):
+
+    @staticmethod
+    def forward(ctx,
+                input,
+                offset,
+                mask,
+                weight,
+                bias=None,
+                stride=1,
+                padding=0,
+                dilation=1,
+                groups=1,
+                deformable_groups=1):
+        ctx.stride = stride
+        ctx.padding = padding
+        ctx.dilation = dilation
+        ctx.groups = groups
+        ctx.deformable_groups = deformable_groups
+        ctx.with_bias = bias is not None
+        if not ctx.with_bias:
+            bias = input.new_empty(1)  # fake tensor
+        if not input.is_cuda:
+            raise NotImplementedError
+        if weight.requires_grad or mask.requires_grad or offset.requires_grad \
+                or input.requires_grad:
+            ctx.save_for_backward(input, offset, mask, weight, bias)
+        output = input.new_empty(ModulatedDeformConvFunction._infer_shape(ctx, input, weight))
+        ctx._bufs = [input.new_empty(0), input.new_empty(0)]
+        deform_conv_ext.modulated_deform_conv_forward(input, weight, bias, ctx._bufs[0], offset, mask, output,
+                                                      ctx._bufs[1], weight.shape[2], weight.shape[3], ctx.stride,
+                                                      ctx.stride, ctx.padding, ctx.padding, ctx.dilation, ctx.dilation,
+                                                      ctx.groups, ctx.deformable_groups, ctx.with_bias)
+        return output
+
+    @staticmethod
+    @once_differentiable
+    def backward(ctx, grad_output):
+        if not grad_output.is_cuda:
+            raise NotImplementedError
+        input, offset, mask, weight, bias = ctx.saved_tensors
+        grad_input = torch.zeros_like(input)
+        grad_offset = torch.zeros_like(offset)
+        grad_mask = torch.zeros_like(mask)
+        grad_weight = torch.zeros_like(weight)
+        grad_bias = torch.zeros_like(bias)
+        deform_conv_ext.modulated_deform_conv_backward(input, weight, bias, ctx._bufs[0], offset, mask, ctx._bufs[1],
+                                                       grad_input, grad_weight, grad_bias, grad_offset, grad_mask,
+                                                       grad_output, weight.shape[2], weight.shape[3], ctx.stride,
+                                                       ctx.stride, ctx.padding, ctx.padding, ctx.dilation, ctx.dilation,
+                                                       ctx.groups, ctx.deformable_groups, ctx.with_bias)
+        if not ctx.with_bias:
+            grad_bias = None
+
+        return (grad_input, grad_offset, grad_mask, grad_weight, grad_bias, None, None, None, None, None)
+
+    @staticmethod
+    def _infer_shape(ctx, input, weight):
+        n = input.size(0)
+        channels_out = weight.size(0)
+        height, width = input.shape[2:4]
+        kernel_h, kernel_w = weight.shape[2:4]
+        height_out = (height + 2 * ctx.padding - (ctx.dilation * (kernel_h - 1) + 1)) // ctx.stride + 1
+        width_out = (width + 2 * ctx.padding - (ctx.dilation * (kernel_w - 1) + 1)) // ctx.stride + 1
+        return n, channels_out, height_out, width_out
+
+
+deform_conv = DeformConvFunction.apply
+modulated_deform_conv = ModulatedDeformConvFunction.apply
+
+
+class DeformConv(nn.Module):
+
+    def __init__(self,
+                 in_channels,
+                 out_channels,
+                 kernel_size,
+                 stride=1,
+                 padding=0,
+                 dilation=1,
+                 groups=1,
+                 deformable_groups=1,
+                 bias=False):
+        super(DeformConv, self).__init__()
+
+        assert not bias
+        assert in_channels % groups == 0, \
+            f'in_channels {in_channels} is not divisible by groups {groups}'
+        assert out_channels % groups == 0, \
+            f'out_channels {out_channels} is not divisible ' \
+            f'by groups {groups}'
+
+        self.in_channels = in_channels
+        self.out_channels = out_channels
+        self.kernel_size = _pair(kernel_size)
+        self.stride = _pair(stride)
+        self.padding = _pair(padding)
+        self.dilation = _pair(dilation)
+        self.groups = groups
+        self.deformable_groups = deformable_groups
+        # enable compatibility with nn.Conv2d
+        self.transposed = False
+        self.output_padding = _single(0)
+
+        self.weight = nn.Parameter(torch.Tensor(out_channels, in_channels // self.groups, *self.kernel_size))
+
+        self.reset_parameters()
+
+    def reset_parameters(self):
+        n = self.in_channels
+        for k in self.kernel_size:
+            n *= k
+        stdv = 1. / math.sqrt(n)
+        self.weight.data.uniform_(-stdv, stdv)
+
+    def forward(self, x, offset):
+        # To fix an assert error in deform_conv_cuda.cpp:128
+        # input image is smaller than kernel
+        input_pad = (x.size(2) < self.kernel_size[0] or x.size(3) < self.kernel_size[1])
+        if input_pad:
+            pad_h = max(self.kernel_size[0] - x.size(2), 0)
+            pad_w = max(self.kernel_size[1] - x.size(3), 0)
+            x = F.pad(x, (0, pad_w, 0, pad_h), 'constant', 0).contiguous()
+            offset = F.pad(offset, (0, pad_w, 0, pad_h), 'constant', 0).contiguous()
+        out = deform_conv(x, offset, self.weight, self.stride, self.padding, self.dilation, self.groups,
+                          self.deformable_groups)
+        if input_pad:
+            out = out[:, :, :out.size(2) - pad_h, :out.size(3) - pad_w].contiguous()
+        return out
+
+
+class DeformConvPack(DeformConv):
+    """A Deformable Conv Encapsulation that acts as normal Conv layers.
+
+    Args:
+        in_channels (int): Same as nn.Conv2d.
+        out_channels (int): Same as nn.Conv2d.
+        kernel_size (int or tuple[int]): Same as nn.Conv2d.
+        stride (int or tuple[int]): Same as nn.Conv2d.
+        padding (int or tuple[int]): Same as nn.Conv2d.
+        dilation (int or tuple[int]): Same as nn.Conv2d.
+        groups (int): Same as nn.Conv2d.
+        bias (bool or str): If specified as `auto`, it will be decided by the
+            norm_cfg. Bias will be set as True if norm_cfg is None, otherwise
+            False.
+    """
+
+    _version = 2
+
+    def __init__(self, *args, **kwargs):
+        super(DeformConvPack, self).__init__(*args, **kwargs)
+
+        self.conv_offset = nn.Conv2d(
+            self.in_channels,
+            self.deformable_groups * 2 * self.kernel_size[0] * self.kernel_size[1],
+            kernel_size=self.kernel_size,
+            stride=_pair(self.stride),
+            padding=_pair(self.padding),
+            dilation=_pair(self.dilation),
+            bias=True)
+        self.init_offset()
+
+    def init_offset(self):
+        self.conv_offset.weight.data.zero_()
+        self.conv_offset.bias.data.zero_()
+
+    def forward(self, x):
+        offset = self.conv_offset(x)
+        return deform_conv(x, offset, self.weight, self.stride, self.padding, self.dilation, self.groups,
+                           self.deformable_groups)
+
+
+class ModulatedDeformConv(nn.Module):
+
+    def __init__(self,
+                 in_channels,
+                 out_channels,
+                 kernel_size,
+                 stride=1,
+                 padding=0,
+                 dilation=1,
+                 groups=1,
+                 deformable_groups=1,
+                 bias=True):
+        super(ModulatedDeformConv, self).__init__()
+        self.in_channels = in_channels
+        self.out_channels = out_channels
+        self.kernel_size = _pair(kernel_size)
+        self.stride = stride
+        self.padding = padding
+        self.dilation = dilation
+        self.groups = groups
+        self.deformable_groups = deformable_groups
+        self.with_bias = bias
+        # enable compatibility with nn.Conv2d
+        self.transposed = False
+        self.output_padding = _single(0)
+
+        self.weight = nn.Parameter(torch.Tensor(out_channels, in_channels // groups, *self.kernel_size))
+        if bias:
+            self.bias = nn.Parameter(torch.Tensor(out_channels))
+        else:
+            self.register_parameter('bias', None)
+        self.init_weights()
+
+    def init_weights(self):
+        n = self.in_channels
+        for k in self.kernel_size:
+            n *= k
+        stdv = 1. / math.sqrt(n)
+        self.weight.data.uniform_(-stdv, stdv)
+        if self.bias is not None:
+            self.bias.data.zero_()
+
+    def forward(self, x, offset, mask):
+        return modulated_deform_conv(x, offset, mask, self.weight, self.bias, self.stride, self.padding, self.dilation,
+                                     self.groups, self.deformable_groups)
+
+
+class ModulatedDeformConvPack(ModulatedDeformConv):
+    """A ModulatedDeformable Conv Encapsulation that acts as normal Conv layers.
+
+    Args:
+        in_channels (int): Same as nn.Conv2d.
+        out_channels (int): Same as nn.Conv2d.
+        kernel_size (int or tuple[int]): Same as nn.Conv2d.
+        stride (int or tuple[int]): Same as nn.Conv2d.
+        padding (int or tuple[int]): Same as nn.Conv2d.
+        dilation (int or tuple[int]): Same as nn.Conv2d.
+        groups (int): Same as nn.Conv2d.
+        bias (bool or str): If specified as `auto`, it will be decided by the
+            norm_cfg. Bias will be set as True if norm_cfg is None, otherwise
+            False.
+    """
+
+    _version = 2
+
+    def __init__(self, *args, **kwargs):
+        super(ModulatedDeformConvPack, self).__init__(*args, **kwargs)
+
+        self.conv_offset = nn.Conv2d(
+            self.in_channels,
+            self.deformable_groups * 3 * self.kernel_size[0] * self.kernel_size[1],
+            kernel_size=self.kernel_size,
+            stride=_pair(self.stride),
+            padding=_pair(self.padding),
+            dilation=_pair(self.dilation),
+            bias=True)
+        self.init_weights()
+
+    def init_weights(self):
+        super(ModulatedDeformConvPack, self).init_weights()
+        if hasattr(self, 'conv_offset'):
+            self.conv_offset.weight.data.zero_()
+            self.conv_offset.bias.data.zero_()
+
+    def forward(self, x):
+        out = self.conv_offset(x)
+        o1, o2, mask = torch.chunk(out, 3, dim=1)
+        offset = torch.cat((o1, o2), dim=1)
+        mask = torch.sigmoid(mask)
+        return modulated_deform_conv(x, offset, mask, self.weight, self.bias, self.stride, self.padding, self.dilation,
+                                     self.groups, self.deformable_groups)

basicsr/ops/dcn/src/deform_conv_cuda.cpp

@@ -0,0 +1,685 @@
+// modify from
+// https://github.com/chengdazhi/Deformable-Convolution-V2-PyTorch/blob/mmdetection/mmdet/ops/dcn/src/deform_conv_cuda.c
+
+#include <torch/extension.h>
+#include <ATen/DeviceGuard.h>
+
+#include <cmath>
+#include <vector>
+
+void deformable_im2col(const at::Tensor data_im, const at::Tensor data_offset,
+                       const int channels, const int height, const int width,
+                       const int ksize_h, const int ksize_w, const int pad_h,
+                       const int pad_w, const int stride_h, const int stride_w,
+                       const int dilation_h, const int dilation_w,
+                       const int parallel_imgs, const int deformable_group,
+                       at::Tensor data_col);
+
+void deformable_col2im(const at::Tensor data_col, const at::Tensor data_offset,
+                       const int channels, const int height, const int width,
+                       const int ksize_h, const int ksize_w, const int pad_h,
+                       const int pad_w, const int stride_h, const int stride_w,
+                       const int dilation_h, const int dilation_w,
+                       const int parallel_imgs, const int deformable_group,
+                       at::Tensor grad_im);
+
+void deformable_col2im_coord(
+    const at::Tensor data_col, const at::Tensor data_im,
+    const at::Tensor data_offset, const int channels, const int height,
+    const int width, const int ksize_h, const int ksize_w, const int pad_h,
+    const int pad_w, const int stride_h, const int stride_w,
+    const int dilation_h, const int dilation_w, const int parallel_imgs,
+    const int deformable_group, at::Tensor grad_offset);
+
+void modulated_deformable_im2col_cuda(
+    const at::Tensor data_im, const at::Tensor data_offset,
+    const at::Tensor data_mask, const int batch_size, const int channels,
+    const int height_im, const int width_im, const int height_col,
+    const int width_col, const int kernel_h, const int kenerl_w,
+    const int pad_h, const int pad_w, const int stride_h, const int stride_w,
+    const int dilation_h, const int dilation_w, const int deformable_group,
+    at::Tensor data_col);
+
+void modulated_deformable_col2im_cuda(
+    const at::Tensor data_col, const at::Tensor data_offset,
+    const at::Tensor data_mask, const int batch_size, const int channels,
+    const int height_im, const int width_im, const int height_col,
+    const int width_col, const int kernel_h, const int kenerl_w,
+    const int pad_h, const int pad_w, const int stride_h, const int stride_w,
+    const int dilation_h, const int dilation_w, const int deformable_group,
+    at::Tensor grad_im);
+
+void modulated_deformable_col2im_coord_cuda(
+    const at::Tensor data_col, const at::Tensor data_im,
+    const at::Tensor data_offset, const at::Tensor data_mask,
+    const int batch_size, const int channels, const int height_im,
+    const int width_im, const int height_col, const int width_col,
+    const int kernel_h, const int kenerl_w, const int pad_h, const int pad_w,
+    const int stride_h, const int stride_w, const int dilation_h,
+    const int dilation_w, const int deformable_group, at::Tensor grad_offset,
+    at::Tensor grad_mask);
+
+void shape_check(at::Tensor input, at::Tensor offset, at::Tensor *gradOutput,
+                 at::Tensor weight, int kH, int kW, int dH, int dW, int padH,
+                 int padW, int dilationH, int dilationW, int group,
+                 int deformable_group) {
+  TORCH_CHECK(weight.ndimension() == 4,
+           "4D weight tensor (nOutputPlane,nInputPlane,kH,kW) expected, "
+           "but got: %s",
+           weight.ndimension());
+
+  TORCH_CHECK(weight.is_contiguous(), "weight tensor has to be contiguous");
+
+  TORCH_CHECK(kW > 0 && kH > 0,
+           "kernel size should be greater than zero, but got kH: %d kW: %d", kH,
+           kW);
+
+  TORCH_CHECK((weight.size(2) == kH && weight.size(3) == kW),
+           "kernel size should be consistent with weight, ",
+           "but got kH: %d kW: %d weight.size(2): %d, weight.size(3): %d", kH,
+           kW, weight.size(2), weight.size(3));
+
+  TORCH_CHECK(dW > 0 && dH > 0,
+           "stride should be greater than zero, but got dH: %d dW: %d", dH, dW);
+
+  TORCH_CHECK(
+      dilationW > 0 && dilationH > 0,
+      "dilation should be greater than 0, but got dilationH: %d dilationW: %d",
+      dilationH, dilationW);
+
+  int ndim = input.ndimension();
+  int dimf = 0;
+  int dimh = 1;
+  int dimw = 2;
+
+  if (ndim == 4) {
+    dimf++;
+    dimh++;
+    dimw++;
+  }
+
+  TORCH_CHECK(ndim == 3 || ndim == 4, "3D or 4D input tensor expected but got: %s",
+           ndim);
+
+  long nInputPlane = weight.size(1) * group;
+  long inputHeight = input.size(dimh);
+  long inputWidth = input.size(dimw);
+  long nOutputPlane = weight.size(0);
+  long outputHeight =
+      (inputHeight + 2 * padH - (dilationH * (kH - 1) + 1)) / dH + 1;
+  long outputWidth =
+      (inputWidth + 2 * padW - (dilationW * (kW - 1) + 1)) / dW + 1;
+
+  TORCH_CHECK(nInputPlane % deformable_group == 0,
+           "input channels must divide deformable group size");
+
+  if (outputWidth < 1 || outputHeight < 1)
+    AT_ERROR(
+        "Given input size: (%ld x %ld x %ld). "
+        "Calculated output size: (%ld x %ld x %ld). Output size is too small",
+        nInputPlane, inputHeight, inputWidth, nOutputPlane, outputHeight,
+        outputWidth);
+
+  TORCH_CHECK(input.size(1) == nInputPlane,
+           "invalid number of input planes, expected: %d, but got: %d",
+           nInputPlane, input.size(1));
+
+  TORCH_CHECK((inputHeight >= kH && inputWidth >= kW),
+           "input image is smaller than kernel");
+
+  TORCH_CHECK((offset.size(2) == outputHeight && offset.size(3) == outputWidth),
+           "invalid spatial size of offset, expected height: %d width: %d, but "
+           "got height: %d width: %d",
+           outputHeight, outputWidth, offset.size(2), offset.size(3));
+
+  TORCH_CHECK((offset.size(1) == deformable_group * 2 * kH * kW),
+           "invalid number of channels of offset");
+
+  if (gradOutput != NULL) {
+    TORCH_CHECK(gradOutput->size(dimf) == nOutputPlane,
+             "invalid number of gradOutput planes, expected: %d, but got: %d",
+             nOutputPlane, gradOutput->size(dimf));
+
+    TORCH_CHECK((gradOutput->size(dimh) == outputHeight &&
+              gradOutput->size(dimw) == outputWidth),
+             "invalid size of gradOutput, expected height: %d width: %d , but "
+             "got height: %d width: %d",
+             outputHeight, outputWidth, gradOutput->size(dimh),
+             gradOutput->size(dimw));
+  }
+}
+
+int deform_conv_forward_cuda(at::Tensor input, at::Tensor weight,
+                             at::Tensor offset, at::Tensor output,
+                             at::Tensor columns, at::Tensor ones, int kW,
+                             int kH, int dW, int dH, int padW, int padH,
+                             int dilationW, int dilationH, int group,
+                             int deformable_group, int im2col_step) {
+  // todo: resize columns to include im2col: done
+  // todo: add im2col_step as input
+  // todo: add new output buffer and transpose it to output (or directly
+  // transpose output) todo: possibly change data indexing because of
+  // parallel_imgs
+
+  shape_check(input, offset, NULL, weight, kH, kW, dH, dW, padH, padW,
+              dilationH, dilationW, group, deformable_group);
+  at::DeviceGuard guard(input.device());
+
+  input = input.contiguous();
+  offset = offset.contiguous();
+  weight = weight.contiguous();
+
+  int batch = 1;
+  if (input.ndimension() == 3) {
+    // Force batch
+    batch = 0;
+    input.unsqueeze_(0);
+    offset.unsqueeze_(0);
+  }
+
+  // todo: assert batchsize dividable by im2col_step
+
+  long batchSize = input.size(0);
+  long nInputPlane = input.size(1);
+  long inputHeight = input.size(2);
+  long inputWidth = input.size(3);
+
+  long nOutputPlane = weight.size(0);
+
+  long outputWidth =
+      (inputWidth + 2 * padW - (dilationW * (kW - 1) + 1)) / dW + 1;
+  long outputHeight =
+      (inputHeight + 2 * padH - (dilationH * (kH - 1) + 1)) / dH + 1;
+
+  TORCH_CHECK((offset.size(0) == batchSize), "invalid batch size of offset");
+
+  output = output.view({batchSize / im2col_step, im2col_step, nOutputPlane,
+                        outputHeight, outputWidth});
+  columns = at::zeros(
+      {nInputPlane * kW * kH, im2col_step * outputHeight * outputWidth},
+      input.options());
+
+  if (ones.ndimension() != 2 ||
+      ones.size(0) * ones.size(1) < outputHeight * outputWidth) {
+    ones = at::ones({outputHeight, outputWidth}, input.options());
+  }
+
+  input = input.view({batchSize / im2col_step, im2col_step, nInputPlane,
+                      inputHeight, inputWidth});
+  offset =
+      offset.view({batchSize / im2col_step, im2col_step,
+                   deformable_group * 2 * kH * kW, outputHeight, outputWidth});
+
+  at::Tensor output_buffer =
+      at::zeros({batchSize / im2col_step, nOutputPlane,
+                 im2col_step * outputHeight, outputWidth},
+                output.options());
+
+  output_buffer = output_buffer.view(
+      {output_buffer.size(0), group, output_buffer.size(1) / group,
+       output_buffer.size(2), output_buffer.size(3)});
+
+  for (int elt = 0; elt < batchSize / im2col_step; elt++) {
+    deformable_im2col(input[elt], offset[elt], nInputPlane, inputHeight,
+                      inputWidth, kH, kW, padH, padW, dH, dW, dilationH,
+                      dilationW, im2col_step, deformable_group, columns);
+
+    columns = columns.view({group, columns.size(0) / group, columns.size(1)});
+    weight = weight.view({group, weight.size(0) / group, weight.size(1),
+                          weight.size(2), weight.size(3)});
+
+    for (int g = 0; g < group; g++) {
+      output_buffer[elt][g] = output_buffer[elt][g]
+                                  .flatten(1)
+                                  .addmm_(weight[g].flatten(1), columns[g])
+                                  .view_as(output_buffer[elt][g]);
+    }
+  }
+
+  output_buffer = output_buffer.view(
+      {output_buffer.size(0), output_buffer.size(1) * output_buffer.size(2),
+       output_buffer.size(3), output_buffer.size(4)});
+
+  output_buffer = output_buffer.view({batchSize / im2col_step, nOutputPlane,
+                                      im2col_step, outputHeight, outputWidth});
+  output_buffer.transpose_(1, 2);
+  output.copy_(output_buffer);
+  output = output.view({batchSize, nOutputPlane, outputHeight, outputWidth});
+
+  input = input.view({batchSize, nInputPlane, inputHeight, inputWidth});
+  offset = offset.view(
+      {batchSize, deformable_group * 2 * kH * kW, outputHeight, outputWidth});
+
+  if (batch == 0) {
+    output = output.view({nOutputPlane, outputHeight, outputWidth});
+    input = input.view({nInputPlane, inputHeight, inputWidth});
+    offset = offset.view({offset.size(1), offset.size(2), offset.size(3)});
+  }
+
+  return 1;
+}
+
+int deform_conv_backward_input_cuda(at::Tensor input, at::Tensor offset,
+                                    at::Tensor gradOutput, at::Tensor gradInput,
+                                    at::Tensor gradOffset, at::Tensor weight,
+                                    at::Tensor columns, int kW, int kH, int dW,
+                                    int dH, int padW, int padH, int dilationW,
+                                    int dilationH, int group,
+                                    int deformable_group, int im2col_step) {
+  shape_check(input, offset, &gradOutput, weight, kH, kW, dH, dW, padH, padW,
+              dilationH, dilationW, group, deformable_group);
+  at::DeviceGuard guard(input.device());
+
+  input = input.contiguous();
+  offset = offset.contiguous();
+  gradOutput = gradOutput.contiguous();
+  weight = weight.contiguous();
+
+  int batch = 1;
+
+  if (input.ndimension() == 3) {
+    // Force batch
+    batch = 0;
+    input = input.view({1, input.size(0), input.size(1), input.size(2)});
+    offset = offset.view({1, offset.size(0), offset.size(1), offset.size(2)});
+    gradOutput = gradOutput.view(
+        {1, gradOutput.size(0), gradOutput.size(1), gradOutput.size(2)});
+  }
+
+  long batchSize = input.size(0);
+  long nInputPlane = input.size(1);
+  long inputHeight = input.size(2);
+  long inputWidth = input.size(3);
+
+  long nOutputPlane = weight.size(0);
+
+  long outputWidth =
+      (inputWidth + 2 * padW - (dilationW * (kW - 1) + 1)) / dW + 1;
+  long outputHeight =
+      (inputHeight + 2 * padH - (dilationH * (kH - 1) + 1)) / dH + 1;
+
+  TORCH_CHECK((offset.size(0) == batchSize), 3, "invalid batch size of offset");
+  gradInput = gradInput.view({batchSize, nInputPlane, inputHeight, inputWidth});
+  columns = at::zeros(
+      {nInputPlane * kW * kH, im2col_step * outputHeight * outputWidth},
+      input.options());
+
+  // change order of grad output
+  gradOutput = gradOutput.view({batchSize / im2col_step, im2col_step,
+                                nOutputPlane, outputHeight, outputWidth});
+  gradOutput.transpose_(1, 2);
+
+  gradInput = gradInput.view({batchSize / im2col_step, im2col_step, nInputPlane,
+                              inputHeight, inputWidth});
+  input = input.view({batchSize / im2col_step, im2col_step, nInputPlane,
+                      inputHeight, inputWidth});
+  gradOffset = gradOffset.view({batchSize / im2col_step, im2col_step,
+                                deformable_group * 2 * kH * kW, outputHeight,
+                                outputWidth});
+  offset =
+      offset.view({batchSize / im2col_step, im2col_step,
+                   deformable_group * 2 * kH * kW, outputHeight, outputWidth});
+
+  for (int elt = 0; elt < batchSize / im2col_step; elt++) {
+    // divide into groups
+    columns = columns.view({group, columns.size(0) / group, columns.size(1)});
+    weight = weight.view({group, weight.size(0) / group, weight.size(1),
+                          weight.size(2), weight.size(3)});
+    gradOutput = gradOutput.view(
+        {gradOutput.size(0), group, gradOutput.size(1) / group,
+         gradOutput.size(2), gradOutput.size(3), gradOutput.size(4)});
+
+    for (int g = 0; g < group; g++) {
+      columns[g] = columns[g].addmm_(weight[g].flatten(1).transpose(0, 1),
+                                     gradOutput[elt][g].flatten(1), 0.0f, 1.0f);
+    }
+
+    columns =
+        columns.view({columns.size(0) * columns.size(1), columns.size(2)});
+    gradOutput = gradOutput.view(
+        {gradOutput.size(0), gradOutput.size(1) * gradOutput.size(2),
+         gradOutput.size(3), gradOutput.size(4), gradOutput.size(5)});
+
+    deformable_col2im_coord(columns, input[elt], offset[elt], nInputPlane,
+                            inputHeight, inputWidth, kH, kW, padH, padW, dH, dW,
+                            dilationH, dilationW, im2col_step, deformable_group,
+                            gradOffset[elt]);
+
+    deformable_col2im(columns, offset[elt], nInputPlane, inputHeight,
+                      inputWidth, kH, kW, padH, padW, dH, dW, dilationH,
+                      dilationW, im2col_step, deformable_group, gradInput[elt]);
+  }
+
+  gradOutput.transpose_(1, 2);
+  gradOutput =
+      gradOutput.view({batchSize, nOutputPlane, outputHeight, outputWidth});
+
+  gradInput = gradInput.view({batchSize, nInputPlane, inputHeight, inputWidth});
+  input = input.view({batchSize, nInputPlane, inputHeight, inputWidth});
+  gradOffset = gradOffset.view(
+      {batchSize, deformable_group * 2 * kH * kW, outputHeight, outputWidth});
+  offset = offset.view(
+      {batchSize, deformable_group * 2 * kH * kW, outputHeight, outputWidth});
+
+  if (batch == 0) {
+    gradOutput = gradOutput.view({nOutputPlane, outputHeight, outputWidth});
+    input = input.view({nInputPlane, inputHeight, inputWidth});
+    gradInput = gradInput.view({nInputPlane, inputHeight, inputWidth});
+    offset = offset.view({offset.size(1), offset.size(2), offset.size(3)});
+    gradOffset =
+        gradOffset.view({offset.size(1), offset.size(2), offset.size(3)});
+  }
+
+  return 1;
+}
+
+int deform_conv_backward_parameters_cuda(
+    at::Tensor input, at::Tensor offset, at::Tensor gradOutput,
+    at::Tensor gradWeight,  // at::Tensor gradBias,
+    at::Tensor columns, at::Tensor ones, int kW, int kH, int dW, int dH,
+    int padW, int padH, int dilationW, int dilationH, int group,
+    int deformable_group, float scale, int im2col_step) {
+  // todo: transpose and reshape outGrad
+  // todo: reshape columns
+  // todo: add im2col_step as input
+
+  shape_check(input, offset, &gradOutput, gradWeight, kH, kW, dH, dW, padH,
+              padW, dilationH, dilationW, group, deformable_group);
+  at::DeviceGuard guard(input.device());
+
+  input = input.contiguous();
+  offset = offset.contiguous();
+  gradOutput = gradOutput.contiguous();
+
+  int batch = 1;
+
+  if (input.ndimension() == 3) {
+    // Force batch
+    batch = 0;
+    input = input.view(
+        at::IntList({1, input.size(0), input.size(1), input.size(2)}));
+    gradOutput = gradOutput.view(
+        {1, gradOutput.size(0), gradOutput.size(1), gradOutput.size(2)});
+  }
+
+  long batchSize = input.size(0);
+  long nInputPlane = input.size(1);
+  long inputHeight = input.size(2);
+  long inputWidth = input.size(3);
+
+  long nOutputPlane = gradWeight.size(0);
+
+  long outputWidth =
+      (inputWidth + 2 * padW - (dilationW * (kW - 1) + 1)) / dW + 1;
+  long outputHeight =
+      (inputHeight + 2 * padH - (dilationH * (kH - 1) + 1)) / dH + 1;
+
+  TORCH_CHECK((offset.size(0) == batchSize), "invalid batch size of offset");
+
+  columns = at::zeros(
+      {nInputPlane * kW * kH, im2col_step * outputHeight * outputWidth},
+      input.options());
+
+  gradOutput = gradOutput.view({batchSize / im2col_step, im2col_step,
+                                nOutputPlane, outputHeight, outputWidth});
+  gradOutput.transpose_(1, 2);
+
+  at::Tensor gradOutputBuffer = at::zeros_like(gradOutput);
+  gradOutputBuffer =
+      gradOutputBuffer.view({batchSize / im2col_step, nOutputPlane, im2col_step,
+                             outputHeight, outputWidth});
+  gradOutputBuffer.copy_(gradOutput);
+  gradOutputBuffer =
+      gradOutputBuffer.view({batchSize / im2col_step, nOutputPlane,
+                             im2col_step * outputHeight, outputWidth});
+
+  gradOutput.transpose_(1, 2);
+  gradOutput =
+      gradOutput.view({batchSize, nOutputPlane, outputHeight, outputWidth});
+
+  input = input.view({batchSize / im2col_step, im2col_step, nInputPlane,
+                      inputHeight, inputWidth});
+  offset =
+      offset.view({batchSize / im2col_step, im2col_step,
+                   deformable_group * 2 * kH * kW, outputHeight, outputWidth});
+
+  for (int elt = 0; elt < batchSize / im2col_step; elt++) {
+    deformable_im2col(input[elt], offset[elt], nInputPlane, inputHeight,
+                      inputWidth, kH, kW, padH, padW, dH, dW, dilationH,
+                      dilationW, im2col_step, deformable_group, columns);
+
+    // divide into group
+    gradOutputBuffer = gradOutputBuffer.view(
+        {gradOutputBuffer.size(0), group, gradOutputBuffer.size(1) / group,
+         gradOutputBuffer.size(2), gradOutputBuffer.size(3)});
+    columns = columns.view({group, columns.size(0) / group, columns.size(1)});
+    gradWeight =
+        gradWeight.view({group, gradWeight.size(0) / group, gradWeight.size(1),
+                         gradWeight.size(2), gradWeight.size(3)});
+
+    for (int g = 0; g < group; g++) {
+      gradWeight[g] = gradWeight[g]
+                          .flatten(1)
+                          .addmm_(gradOutputBuffer[elt][g].flatten(1),
+                                  columns[g].transpose(1, 0), 1.0, scale)
+                          .view_as(gradWeight[g]);
+    }
+    gradOutputBuffer = gradOutputBuffer.view(
+        {gradOutputBuffer.size(0),
+         gradOutputBuffer.size(1) * gradOutputBuffer.size(2),
+         gradOutputBuffer.size(3), gradOutputBuffer.size(4)});
+    columns =
+        columns.view({columns.size(0) * columns.size(1), columns.size(2)});
+    gradWeight = gradWeight.view({gradWeight.size(0) * gradWeight.size(1),
+                                  gradWeight.size(2), gradWeight.size(3),
+                                  gradWeight.size(4)});
+  }
+
+  input = input.view({batchSize, nInputPlane, inputHeight, inputWidth});
+  offset = offset.view(
+      {batchSize, deformable_group * 2 * kH * kW, outputHeight, outputWidth});
+
+  if (batch == 0) {
+    gradOutput = gradOutput.view({nOutputPlane, outputHeight, outputWidth});
+    input = input.view({nInputPlane, inputHeight, inputWidth});
+  }
+
+  return 1;
+}
+
+void modulated_deform_conv_cuda_forward(
+    at::Tensor input, at::Tensor weight, at::Tensor bias, at::Tensor ones,
+    at::Tensor offset, at::Tensor mask, at::Tensor output, at::Tensor columns,
+    int kernel_h, int kernel_w, const int stride_h, const int stride_w,
+    const int pad_h, const int pad_w, const int dilation_h,
+    const int dilation_w, const int group, const int deformable_group,
+    const bool with_bias) {
+  TORCH_CHECK(input.is_contiguous(), "input tensor has to be contiguous");
+  TORCH_CHECK(weight.is_contiguous(), "weight tensor has to be contiguous");
+  at::DeviceGuard guard(input.device());
+
+  const int batch = input.size(0);
+  const int channels = input.size(1);
+  const int height = input.size(2);
+  const int width = input.size(3);
+
+  const int channels_out = weight.size(0);
+  const int channels_kernel = weight.size(1);
+  const int kernel_h_ = weight.size(2);
+  const int kernel_w_ = weight.size(3);
+
+  if (kernel_h_ != kernel_h || kernel_w_ != kernel_w)
+    AT_ERROR("Input shape and kernel shape wont match: (%d x %d vs %d x %d).",
+             kernel_h_, kernel_w, kernel_h_, kernel_w_);
+  if (channels != channels_kernel * group)
+    AT_ERROR("Input shape and kernel channels wont match: (%d vs %d).",
+             channels, channels_kernel * group);
+
+  const int height_out =
+      (height + 2 * pad_h - (dilation_h * (kernel_h - 1) + 1)) / stride_h + 1;
+  const int width_out =
+      (width + 2 * pad_w - (dilation_w * (kernel_w - 1) + 1)) / stride_w + 1;
+
+  if (ones.ndimension() != 2 ||
+      ones.size(0) * ones.size(1) < height_out * width_out) {
+    // Resize plane and fill with ones...
+    ones = at::ones({height_out, width_out}, input.options());
+  }
+
+  // resize output
+  output = output.view({batch, channels_out, height_out, width_out}).zero_();
+  // resize temporary columns
+  columns =
+      at::zeros({channels * kernel_h * kernel_w, 1 * height_out * width_out},
+                input.options());
+
+  output = output.view({output.size(0), group, output.size(1) / group,
+                        output.size(2), output.size(3)});
+
+  for (int b = 0; b < batch; b++) {
+    modulated_deformable_im2col_cuda(
+        input[b], offset[b], mask[b], 1, channels, height, width, height_out,
+        width_out, kernel_h, kernel_w, pad_h, pad_w, stride_h, stride_w,
+        dilation_h, dilation_w, deformable_group, columns);
+
+    // divide into group
+    weight = weight.view({group, weight.size(0) / group, weight.size(1),
+                          weight.size(2), weight.size(3)});
+    columns = columns.view({group, columns.size(0) / group, columns.size(1)});
+
+    for (int g = 0; g < group; g++) {
+      output[b][g] = output[b][g]
+                         .flatten(1)
+                         .addmm_(weight[g].flatten(1), columns[g])
+                         .view_as(output[b][g]);
+    }
+
+    weight = weight.view({weight.size(0) * weight.size(1), weight.size(2),
+                          weight.size(3), weight.size(4)});
+    columns =
+        columns.view({columns.size(0) * columns.size(1), columns.size(2)});
+  }
+
+  output = output.view({output.size(0), output.size(1) * output.size(2),
+                        output.size(3), output.size(4)});
+
+  if (with_bias) {
+    output += bias.view({1, bias.size(0), 1, 1});
+  }
+}
+
+void modulated_deform_conv_cuda_backward(
+    at::Tensor input, at::Tensor weight, at::Tensor bias, at::Tensor ones,
+    at::Tensor offset, at::Tensor mask, at::Tensor columns,
+    at::Tensor grad_input, at::Tensor grad_weight, at::Tensor grad_bias,
+    at::Tensor grad_offset, at::Tensor grad_mask, at::Tensor grad_output,
+    int kernel_h, int kernel_w, int stride_h, int stride_w, int pad_h,
+    int pad_w, int dilation_h, int dilation_w, int group, int deformable_group,
+    const bool with_bias) {
+  TORCH_CHECK(input.is_contiguous(), "input tensor has to be contiguous");
+  TORCH_CHECK(weight.is_contiguous(), "weight tensor has to be contiguous");
+  at::DeviceGuard guard(input.device());
+
+  const int batch = input.size(0);
+  const int channels = input.size(1);
+  const int height = input.size(2);
+  const int width = input.size(3);
+
+  const int channels_kernel = weight.size(1);
+  const int kernel_h_ = weight.size(2);
+  const int kernel_w_ = weight.size(3);
+  if (kernel_h_ != kernel_h || kernel_w_ != kernel_w)
+    AT_ERROR("Input shape and kernel shape wont match: (%d x %d vs %d x %d).",
+             kernel_h_, kernel_w, kernel_h_, kernel_w_);
+  if (channels != channels_kernel * group)
+    AT_ERROR("Input shape and kernel channels wont match: (%d vs %d).",
+             channels, channels_kernel * group);
+
+  const int height_out =
+      (height + 2 * pad_h - (dilation_h * (kernel_h - 1) + 1)) / stride_h + 1;
+  const int width_out =
+      (width + 2 * pad_w - (dilation_w * (kernel_w - 1) + 1)) / stride_w + 1;
+
+  if (ones.ndimension() != 2 ||
+      ones.size(0) * ones.size(1) < height_out * width_out) {
+    // Resize plane and fill with ones...
+    ones = at::ones({height_out, width_out}, input.options());
+  }
+
+  grad_input = grad_input.view({batch, channels, height, width});
+  columns = at::zeros({channels * kernel_h * kernel_w, height_out * width_out},
+                      input.options());
+
+  grad_output =
+      grad_output.view({grad_output.size(0), group, grad_output.size(1) / group,
+                        grad_output.size(2), grad_output.size(3)});
+
+  for (int b = 0; b < batch; b++) {
+    // divide int group
+    columns = columns.view({group, columns.size(0) / group, columns.size(1)});
+    weight = weight.view({group, weight.size(0) / group, weight.size(1),
+                          weight.size(2), weight.size(3)});
+
+    for (int g = 0; g < group; g++) {
+      columns[g].addmm_(weight[g].flatten(1).transpose(0, 1),
+                        grad_output[b][g].flatten(1), 0.0f, 1.0f);
+    }
+
+    columns =
+        columns.view({columns.size(0) * columns.size(1), columns.size(2)});
+    weight = weight.view({weight.size(0) * weight.size(1), weight.size(2),
+                          weight.size(3), weight.size(4)});
+
+    // gradient w.r.t. input coordinate data
+    modulated_deformable_col2im_coord_cuda(
+        columns, input[b], offset[b], mask[b], 1, channels, height, width,
+        height_out, width_out, kernel_h, kernel_w, pad_h, pad_w, stride_h,
+        stride_w, dilation_h, dilation_w, deformable_group, grad_offset[b],
+        grad_mask[b]);
+    // gradient w.r.t. input data
+    modulated_deformable_col2im_cuda(
+        columns, offset[b], mask[b], 1, channels, height, width, height_out,
+        width_out, kernel_h, kernel_w, pad_h, pad_w, stride_h, stride_w,
+        dilation_h, dilation_w, deformable_group, grad_input[b]);
+
+    // gradient w.r.t. weight, dWeight should accumulate across the batch and
+    // group
+    modulated_deformable_im2col_cuda(
+        input[b], offset[b], mask[b], 1, channels, height, width, height_out,
+        width_out, kernel_h, kernel_w, pad_h, pad_w, stride_h, stride_w,
+        dilation_h, dilation_w, deformable_group, columns);
+
+    columns = columns.view({group, columns.size(0) / group, columns.size(1)});
+    grad_weight = grad_weight.view({group, grad_weight.size(0) / group,
+                                    grad_weight.size(1), grad_weight.size(2),
+                                    grad_weight.size(3)});
+    if (with_bias)
+      grad_bias = grad_bias.view({group, grad_bias.size(0) / group});
+
+    for (int g = 0; g < group; g++) {
+      grad_weight[g] =
+          grad_weight[g]
+              .flatten(1)
+              .addmm_(grad_output[b][g].flatten(1), columns[g].transpose(0, 1))
+              .view_as(grad_weight[g]);
+      if (with_bias) {
+        grad_bias[g] =
+            grad_bias[g]
+                .view({-1, 1})
+                .addmm_(grad_output[b][g].flatten(1), ones.view({-1, 1}))
+                .view(-1);
+      }
+    }
+
+    columns =
+        columns.view({columns.size(0) * columns.size(1), columns.size(2)});
+    grad_weight = grad_weight.view({grad_weight.size(0) * grad_weight.size(1),
+                                    grad_weight.size(2), grad_weight.size(3),
+                                    grad_weight.size(4)});
+    if (with_bias)
+      grad_bias = grad_bias.view({grad_bias.size(0) * grad_bias.size(1)});
+  }
+  grad_output = grad_output.view({grad_output.size(0) * grad_output.size(1),
+                                  grad_output.size(2), grad_output.size(3),
+                                  grad_output.size(4)});
+}

basicsr/ops/dcn/src/deform_conv_cuda_kernel.cu

@@ -0,0 +1,867 @@
+/*!
+ ******************* BEGIN Caffe Copyright Notice and Disclaimer ****************
+ *
+ * COPYRIGHT
+ *
+ * All contributions by the University of California:
+ * Copyright (c) 2014-2017 The Regents of the University of California (Regents)
+ * All rights reserved.
+ *
+ * All other contributions:
+ * Copyright (c) 2014-2017, the respective contributors
+ * All rights reserved.
+ *
+ * Caffe uses a shared copyright model: each contributor holds copyright over
+ * their contributions to Caffe. The project versioning records all such
+ * contribution and copyright details. If a contributor wants to further mark
+ * their specific copyright on a particular contribution, they should indicate
+ * their copyright solely in the commit message of the change when it is
+ * committed.
+ *
+ * LICENSE
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * CONTRIBUTION AGREEMENT
+ *
+ * By contributing to the BVLC/caffe repository through pull-request, comment,
+ * or otherwise, the contributor releases their content to the
+ * license and copyright terms herein.
+ *
+ ***************** END Caffe Copyright Notice and Disclaimer ********************
+ *
+ * Copyright (c) 2018 Microsoft
+ * Licensed under The MIT License [see LICENSE for details]
+ * \file modulated_deformable_im2col.cuh
+ * \brief Function definitions of converting an image to
+ * column matrix based on kernel, padding, dilation, and offset.
+ * These functions are mainly used in deformable convolution operators.
+ * \ref: https://arxiv.org/abs/1703.06211
+ * \author Yuwen Xiong, Haozhi Qi, Jifeng Dai, Xizhou Zhu, Han Hu, Dazhi Cheng
+ */
+
+// modified from https://github.com/chengdazhi/Deformable-Convolution-V2-PyTorch/blob/mmdetection/mmdet/ops/dcn/src/deform_conv_cuda_kernel.cu
+
+#include <ATen/ATen.h>
+#include <ATen/cuda/CUDAContext.h>
+#include <THC/THCAtomics.cuh>
+#include <stdio.h>
+#include <math.h>
+#include <float.h>
+
+using namespace at;
+
+#define CUDA_KERNEL_LOOP(i, n)                                 \
+  for (int i = blockIdx.x * blockDim.x + threadIdx.x; i < (n); \
+       i += blockDim.x * gridDim.x)
+
+const int CUDA_NUM_THREADS = 1024;
+const int kMaxGridNum = 65535;
+
+inline int GET_BLOCKS(const int N)
+{
+  return std::min(kMaxGridNum, (N + CUDA_NUM_THREADS - 1) / CUDA_NUM_THREADS);
+}
+
+template <typename scalar_t>
+__device__ scalar_t deformable_im2col_bilinear(const scalar_t *bottom_data, const int data_width,
+                                               const int height, const int width, scalar_t h, scalar_t w)
+{
+
+  int h_low = floor(h);
+  int w_low = floor(w);
+  int h_high = h_low + 1;
+  int w_high = w_low + 1;
+
+  scalar_t lh = h - h_low;
+  scalar_t lw = w - w_low;
+  scalar_t hh = 1 - lh, hw = 1 - lw;
+
+  scalar_t v1 = 0;
+  if (h_low >= 0 && w_low >= 0)
+    v1 = bottom_data[h_low * data_width + w_low];
+  scalar_t v2 = 0;
+  if (h_low >= 0 && w_high <= width - 1)
+    v2 = bottom_data[h_low * data_width + w_high];
+  scalar_t v3 = 0;
+  if (h_high <= height - 1 && w_low >= 0)
+    v3 = bottom_data[h_high * data_width + w_low];
+  scalar_t v4 = 0;
+  if (h_high <= height - 1 && w_high <= width - 1)
+    v4 = bottom_data[h_high * data_width + w_high];
+
+  scalar_t w1 = hh * hw, w2 = hh * lw, w3 = lh * hw, w4 = lh * lw;
+
+  scalar_t val = (w1 * v1 + w2 * v2 + w3 * v3 + w4 * v4);
+  return val;
+}
+
+template <typename scalar_t>
+__device__ scalar_t get_gradient_weight(scalar_t argmax_h, scalar_t argmax_w,
+                                        const int h, const int w, const int height, const int width)
+{
+
+  if (argmax_h <= -1 || argmax_h >= height || argmax_w <= -1 || argmax_w >= width)
+  {
+    //empty
+    return 0;
+  }
+
+  int argmax_h_low = floor(argmax_h);
+  int argmax_w_low = floor(argmax_w);
+  int argmax_h_high = argmax_h_low + 1;
+  int argmax_w_high = argmax_w_low + 1;
+
+  scalar_t weight = 0;
+  if (h == argmax_h_low && w == argmax_w_low)
+    weight = (h + 1 - argmax_h) * (w + 1 - argmax_w);
+  if (h == argmax_h_low && w == argmax_w_high)
+    weight = (h + 1 - argmax_h) * (argmax_w + 1 - w);
+  if (h == argmax_h_high && w == argmax_w_low)
+    weight = (argmax_h + 1 - h) * (w + 1 - argmax_w);
+  if (h == argmax_h_high && w == argmax_w_high)
+    weight = (argmax_h + 1 - h) * (argmax_w + 1 - w);
+  return weight;
+}
+
+template <typename scalar_t>
+__device__ scalar_t get_coordinate_weight(scalar_t argmax_h, scalar_t argmax_w,
+                                          const int height, const int width, const scalar_t *im_data,
+                                          const int data_width, const int bp_dir)
+{
+
+  if (argmax_h <= -1 || argmax_h >= height || argmax_w <= -1 || argmax_w >= width)
+  {
+    //empty
+    return 0;
+  }
+
+  int argmax_h_low = floor(argmax_h);
+  int argmax_w_low = floor(argmax_w);
+  int argmax_h_high = argmax_h_low + 1;
+  int argmax_w_high = argmax_w_low + 1;
+
+  scalar_t weight = 0;
+
+  if (bp_dir == 0)
+  {
+    if (argmax_h_low >= 0 && argmax_w_low >= 0)
+      weight += -1 * (argmax_w_low + 1 - argmax_w) * im_data[argmax_h_low * data_width + argmax_w_low];
+    if (argmax_h_low >= 0 && argmax_w_high <= width - 1)
+      weight += -1 * (argmax_w - argmax_w_low) * im_data[argmax_h_low * data_width + argmax_w_high];
+    if (argmax_h_high <= height - 1 && argmax_w_low >= 0)
+      weight += (argmax_w_low + 1 - argmax_w) * im_data[argmax_h_high * data_width + argmax_w_low];
+    if (argmax_h_high <= height - 1 && argmax_w_high <= width - 1)
+      weight += (argmax_w - argmax_w_low) * im_data[argmax_h_high * data_width + argmax_w_high];
+  }
+  else if (bp_dir == 1)
+  {
+    if (argmax_h_low >= 0 && argmax_w_low >= 0)
+      weight += -1 * (argmax_h_low + 1 - argmax_h) * im_data[argmax_h_low * data_width + argmax_w_low];
+    if (argmax_h_low >= 0 && argmax_w_high <= width - 1)
+      weight += (argmax_h_low + 1 - argmax_h) * im_data[argmax_h_low * data_width + argmax_w_high];
+    if (argmax_h_high <= height - 1 && argmax_w_low >= 0)
+      weight += -1 * (argmax_h - argmax_h_low) * im_data[argmax_h_high * data_width + argmax_w_low];
+    if (argmax_h_high <= height - 1 && argmax_w_high <= width - 1)
+      weight += (argmax_h - argmax_h_low) * im_data[argmax_h_high * data_width + argmax_w_high];
+  }
+
+  return weight;
+}
+
+template <typename scalar_t>
+__global__ void deformable_im2col_gpu_kernel(const int n, const scalar_t *data_im, const scalar_t *data_offset,
+                                             const int height, const int width, const int kernel_h, const int kernel_w,
+                                             const int pad_h, const int pad_w, const int stride_h, const int stride_w,
+                                             const int dilation_h, const int dilation_w, const int channel_per_deformable_group,
+                                             const int batch_size, const int num_channels, const int deformable_group,
+                                             const int height_col, const int width_col,
+                                             scalar_t *data_col)
+{
+  CUDA_KERNEL_LOOP(index, n)
+  {
+    // index index of output matrix
+    const int w_col = index % width_col;
+    const int h_col = (index / width_col) % height_col;
+    const int b_col = (index / width_col / height_col) % batch_size;
+    const int c_im = (index / width_col / height_col) / batch_size;
+    const int c_col = c_im * kernel_h * kernel_w;
+
+    // compute deformable group index
+    const int deformable_group_index = c_im / channel_per_deformable_group;
+
+    const int h_in = h_col * stride_h - pad_h;
+    const int w_in = w_col * stride_w - pad_w;
+    scalar_t *data_col_ptr = data_col + ((c_col * batch_size + b_col) * height_col + h_col) * width_col + w_col;
+    //const scalar_t* data_im_ptr = data_im + ((b_col * num_channels + c_im) * height + h_in) * width + w_in;
+    const scalar_t *data_im_ptr = data_im + (b_col * num_channels + c_im) * height * width;
+    const scalar_t *data_offset_ptr = data_offset + (b_col * deformable_group + deformable_group_index) * 2 * kernel_h * kernel_w * height_col * width_col;
+
+    for (int i = 0; i < kernel_h; ++i)
+    {
+      for (int j = 0; j < kernel_w; ++j)
+      {
+        const int data_offset_h_ptr = ((2 * (i * kernel_w + j)) * height_col + h_col) * width_col + w_col;
+        const int data_offset_w_ptr = ((2 * (i * kernel_w + j) + 1) * height_col + h_col) * width_col + w_col;
+        const scalar_t offset_h = data_offset_ptr[data_offset_h_ptr];
+        const scalar_t offset_w = data_offset_ptr[data_offset_w_ptr];
+        scalar_t val = static_cast<scalar_t>(0);
+        const scalar_t h_im = h_in + i * dilation_h + offset_h;
+        const scalar_t w_im = w_in + j * dilation_w + offset_w;
+        if (h_im > -1 && w_im > -1 && h_im < height && w_im < width)
+        {
+          //const scalar_t map_h = i * dilation_h + offset_h;
+          //const scalar_t map_w = j * dilation_w + offset_w;
+          //const int cur_height = height - h_in;
+          //const int cur_width = width - w_in;
+          //val = deformable_im2col_bilinear(data_im_ptr, width, cur_height, cur_width, map_h, map_w);
+          val = deformable_im2col_bilinear(data_im_ptr, width, height, width, h_im, w_im);
+        }
+        *data_col_ptr = val;
+        data_col_ptr += batch_size * height_col * width_col;
+      }
+    }
+  }
+}
+
+void deformable_im2col(
+    const at::Tensor data_im, const at::Tensor data_offset, const int channels,
+    const int height, const int width, const int ksize_h, const int ksize_w,
+    const int pad_h, const int pad_w, const int stride_h, const int stride_w,
+    const int dilation_h, const int dilation_w, const int parallel_imgs,
+    const int deformable_group, at::Tensor data_col)
+{
+  // num_axes should be smaller than block size
+  // todo: check parallel_imgs is correctly passed in
+  int height_col = (height + 2 * pad_h - (dilation_h * (ksize_h - 1) + 1)) / stride_h + 1;
+  int width_col = (width + 2 * pad_w - (dilation_w * (ksize_w - 1) + 1)) / stride_w + 1;
+  int num_kernels = channels * height_col * width_col * parallel_imgs;
+  int channel_per_deformable_group = channels / deformable_group;
+
+  AT_DISPATCH_FLOATING_TYPES_AND_HALF(
+      data_im.scalar_type(), "deformable_im2col_gpu", ([&] {
+        const scalar_t *data_im_ = data_im.data_ptr<scalar_t>();
+        const scalar_t *data_offset_ = data_offset.data_ptr<scalar_t>();
+        scalar_t *data_col_ = data_col.data_ptr<scalar_t>();
+
+        deformable_im2col_gpu_kernel<<<GET_BLOCKS(num_kernels), CUDA_NUM_THREADS, 0, at::cuda::getCurrentCUDAStream()>>>(
+            num_kernels, data_im_, data_offset_, height, width, ksize_h, ksize_w,
+            pad_h, pad_w, stride_h, stride_w, dilation_h, dilation_w,
+            channel_per_deformable_group, parallel_imgs, channels, deformable_group,
+            height_col, width_col, data_col_);
+      }));
+
+  cudaError_t err = cudaGetLastError();
+  if (err != cudaSuccess)
+  {
+    printf("error in deformable_im2col: %s\n", cudaGetErrorString(err));
+  }
+}
+
+template <typename scalar_t>
+__global__ void deformable_col2im_gpu_kernel(
+    const int n, const scalar_t *data_col, const scalar_t *data_offset,
+    const int channels, const int height, const int width,
+    const int kernel_h, const int kernel_w,
+    const int pad_h, const int pad_w,
+    const int stride_h, const int stride_w,
+    const int dilation_h, const int dilation_w,
+    const int channel_per_deformable_group,
+    const int batch_size, const int deformable_group,
+    const int height_col, const int width_col,
+    scalar_t *grad_im)
+{
+  CUDA_KERNEL_LOOP(index, n)
+  {
+    const int j = (index / width_col / height_col / batch_size) % kernel_w;
+    const int i = (index / width_col / height_col / batch_size / kernel_w) % kernel_h;
+    const int c = index / width_col / height_col / batch_size / kernel_w / kernel_h;
+    // compute the start and end of the output
+
+    const int deformable_group_index = c / channel_per_deformable_group;
+
+    int w_out = index % width_col;
+    int h_out = (index / width_col) % height_col;
+    int b = (index / width_col / height_col) % batch_size;
+    int w_in = w_out * stride_w - pad_w;
+    int h_in = h_out * stride_h - pad_h;
+
+    const scalar_t *data_offset_ptr = data_offset + (b * deformable_group + deformable_group_index) *
+                                                        2 * kernel_h * kernel_w * height_col * width_col;
+    const int data_offset_h_ptr = ((2 * (i * kernel_w + j)) * height_col + h_out) * width_col + w_out;
+    const int data_offset_w_ptr = ((2 * (i * kernel_w + j) + 1) * height_col + h_out) * width_col + w_out;
+    const scalar_t offset_h = data_offset_ptr[data_offset_h_ptr];
+    const scalar_t offset_w = data_offset_ptr[data_offset_w_ptr];
+    const scalar_t cur_inv_h_data = h_in + i * dilation_h + offset_h;
+    const scalar_t cur_inv_w_data = w_in + j * dilation_w + offset_w;
+
+    const scalar_t cur_top_grad = data_col[index];
+    const int cur_h = (int)cur_inv_h_data;
+    const int cur_w = (int)cur_inv_w_data;
+    for (int dy = -2; dy <= 2; dy++)
+    {
+      for (int dx = -2; dx <= 2; dx++)
+      {
+        if (cur_h + dy >= 0 && cur_h + dy < height &&
+            cur_w + dx >= 0 && cur_w + dx < width &&
+            abs(cur_inv_h_data - (cur_h + dy)) < 1 &&
+            abs(cur_inv_w_data - (cur_w + dx)) < 1)
+        {
+          int cur_bottom_grad_pos = ((b * channels + c) * height + cur_h + dy) * width + cur_w + dx;
+          scalar_t weight = get_gradient_weight(cur_inv_h_data, cur_inv_w_data, cur_h + dy, cur_w + dx, height, width);
+          atomicAdd(grad_im + cur_bottom_grad_pos, weight * cur_top_grad);
+        }
+      }
+    }
+  }
+}
+
+void deformable_col2im(
+    const at::Tensor data_col, const at::Tensor data_offset, const int channels,
+    const int height, const int width, const int ksize_h,
+    const int ksize_w, const int pad_h, const int pad_w,
+    const int stride_h, const int stride_w,
+    const int dilation_h, const int dilation_w,
+    const int parallel_imgs, const int deformable_group,
+    at::Tensor grad_im)
+{
+
+  // todo: make sure parallel_imgs is passed in correctly
+  int height_col = (height + 2 * pad_h - (dilation_h * (ksize_h - 1) + 1)) / stride_h + 1;
+  int width_col = (width + 2 * pad_w - (dilation_w * (ksize_w - 1) + 1)) / stride_w + 1;
+  int num_kernels = channels * ksize_h * ksize_w * height_col * width_col * parallel_imgs;
+  int channel_per_deformable_group = channels / deformable_group;
+
+  AT_DISPATCH_FLOATING_TYPES_AND_HALF(
+      data_col.scalar_type(), "deformable_col2im_gpu", ([&] {
+        const scalar_t *data_col_ = data_col.data_ptr<scalar_t>();
+        const scalar_t *data_offset_ = data_offset.data_ptr<scalar_t>();
+        scalar_t *grad_im_ = grad_im.data_ptr<scalar_t>();
+
+        deformable_col2im_gpu_kernel<<<GET_BLOCKS(num_kernels), CUDA_NUM_THREADS, 0, at::cuda::getCurrentCUDAStream()>>>(
+            num_kernels, data_col_, data_offset_, channels, height, width, ksize_h,
+            ksize_w, pad_h, pad_w, stride_h, stride_w,
+            dilation_h, dilation_w, channel_per_deformable_group,
+            parallel_imgs, deformable_group, height_col, width_col, grad_im_);
+      }));
+
+  cudaError_t err = cudaGetLastError();
+  if (err != cudaSuccess)
+  {
+    printf("error in deformable_col2im: %s\n", cudaGetErrorString(err));
+  }
+}
+
+template <typename scalar_t>
+__global__ void deformable_col2im_coord_gpu_kernel(const int n, const scalar_t *data_col,
+                                                   const scalar_t *data_im, const scalar_t *data_offset,
+                                                   const int channels, const int height, const int width,
+                                                   const int kernel_h, const int kernel_w,
+                                                   const int pad_h, const int pad_w,
+                                                   const int stride_h, const int stride_w,
+                                                   const int dilation_h, const int dilation_w,
+                                                   const int channel_per_deformable_group,
+                                                   const int batch_size, const int offset_channels, const int deformable_group,
+                                                   const int height_col, const int width_col, scalar_t *grad_offset)
+{
+  CUDA_KERNEL_LOOP(index, n)
+  {
+    scalar_t val = 0;
+    int w = index % width_col;
+    int h = (index / width_col) % height_col;
+    int c = (index / width_col / height_col) % offset_channels;
+    int b = (index / width_col / height_col) / offset_channels;
+    // compute the start and end of the output
+
+    const int deformable_group_index = c / (2 * kernel_h * kernel_w);
+    const int col_step = kernel_h * kernel_w;
+    int cnt = 0;
+    const scalar_t *data_col_ptr = data_col + deformable_group_index * channel_per_deformable_group *
+                                                  batch_size * width_col * height_col;
+    const scalar_t *data_im_ptr = data_im + (b * deformable_group + deformable_group_index) *
+                                                channel_per_deformable_group / kernel_h / kernel_w * height * width;
+    const scalar_t *data_offset_ptr = data_offset + (b * deformable_group + deformable_group_index) * 2 *
+                                                        kernel_h * kernel_w * height_col * width_col;
+
+    const int offset_c = c - deformable_group_index * 2 * kernel_h * kernel_w;
+
+    for (int col_c = (offset_c / 2); col_c < channel_per_deformable_group; col_c += col_step)
+    {
+      const int col_pos = (((col_c * batch_size + b) * height_col) + h) * width_col + w;
+      const int bp_dir = offset_c % 2;
+
+      int j = (col_pos / width_col / height_col / batch_size) % kernel_w;
+      int i = (col_pos / width_col / height_col / batch_size / kernel_w) % kernel_h;
+      int w_out = col_pos % width_col;
+      int h_out = (col_pos / width_col) % height_col;
+      int w_in = w_out * stride_w - pad_w;
+      int h_in = h_out * stride_h - pad_h;
+      const int data_offset_h_ptr = (((2 * (i * kernel_w + j)) * height_col + h_out) * width_col + w_out);
+      const int data_offset_w_ptr = (((2 * (i * kernel_w + j) + 1) * height_col + h_out) * width_col + w_out);
+      const scalar_t offset_h = data_offset_ptr[data_offset_h_ptr];
+      const scalar_t offset_w = data_offset_ptr[data_offset_w_ptr];
+      scalar_t inv_h = h_in + i * dilation_h + offset_h;
+      scalar_t inv_w = w_in + j * dilation_w + offset_w;
+      if (inv_h <= -1 || inv_w <= -1 || inv_h >= height || inv_w >= width)
+      {
+        inv_h = inv_w = -2;
+      }
+      const scalar_t weight = get_coordinate_weight(
+          inv_h, inv_w,
+          height, width, data_im_ptr + cnt * height * width, width, bp_dir);
+      val += weight * data_col_ptr[col_pos];
+      cnt += 1;
+    }
+
+    grad_offset[index] = val;
+  }
+}
+
+void deformable_col2im_coord(
+    const at::Tensor data_col, const at::Tensor data_im, const at::Tensor data_offset,
+    const int channels, const int height, const int width, const int ksize_h,
+    const int ksize_w, const int pad_h, const int pad_w, const int stride_h,
+    const int stride_w, const int dilation_h, const int dilation_w,
+    const int parallel_imgs, const int deformable_group, at::Tensor grad_offset)
+{
+
+  int height_col = (height + 2 * pad_h - (dilation_h * (ksize_h - 1) + 1)) / stride_h + 1;
+  int width_col = (width + 2 * pad_w - (dilation_w * (ksize_w - 1) + 1)) / stride_w + 1;
+  int num_kernels = height_col * width_col * 2 * ksize_h * ksize_w * deformable_group * parallel_imgs;
+  int channel_per_deformable_group = channels * ksize_h * ksize_w / deformable_group;
+
+  AT_DISPATCH_FLOATING_TYPES_AND_HALF(
+      data_col.scalar_type(), "deformable_col2im_coord_gpu", ([&] {
+        const scalar_t *data_col_ = data_col.data_ptr<scalar_t>();
+        const scalar_t *data_im_ = data_im.data_ptr<scalar_t>();
+        const scalar_t *data_offset_ = data_offset.data_ptr<scalar_t>();
+        scalar_t *grad_offset_ = grad_offset.data_ptr<scalar_t>();
+
+        deformable_col2im_coord_gpu_kernel<<<GET_BLOCKS(num_kernels), CUDA_NUM_THREADS, 0, at::cuda::getCurrentCUDAStream()>>>(
+            num_kernels, data_col_, data_im_, data_offset_, channels, height, width,
+            ksize_h, ksize_w, pad_h, pad_w, stride_h, stride_w,
+            dilation_h, dilation_w, channel_per_deformable_group,
+            parallel_imgs, 2 * ksize_h * ksize_w * deformable_group, deformable_group,
+            height_col, width_col, grad_offset_);
+      }));
+}
+
+template <typename scalar_t>
+__device__ scalar_t dmcn_im2col_bilinear(const scalar_t *bottom_data, const int data_width,
+                                         const int height, const int width, scalar_t h, scalar_t w)
+{
+  int h_low = floor(h);
+  int w_low = floor(w);
+  int h_high = h_low + 1;
+  int w_high = w_low + 1;
+
+  scalar_t lh = h - h_low;
+  scalar_t lw = w - w_low;
+  scalar_t hh = 1 - lh, hw = 1 - lw;
+
+  scalar_t v1 = 0;
+  if (h_low >= 0 && w_low >= 0)
+    v1 = bottom_data[h_low * data_width + w_low];
+  scalar_t v2 = 0;
+  if (h_low >= 0 && w_high <= width - 1)
+    v2 = bottom_data[h_low * data_width + w_high];
+  scalar_t v3 = 0;
+  if (h_high <= height - 1 && w_low >= 0)
+    v3 = bottom_data[h_high * data_width + w_low];
+  scalar_t v4 = 0;
+  if (h_high <= height - 1 && w_high <= width - 1)
+    v4 = bottom_data[h_high * data_width + w_high];
+
+  scalar_t w1 = hh * hw, w2 = hh * lw, w3 = lh * hw, w4 = lh * lw;
+
+  scalar_t val = (w1 * v1 + w2 * v2 + w3 * v3 + w4 * v4);
+  return val;
+}
+
+template <typename scalar_t>
+__device__ scalar_t dmcn_get_gradient_weight(scalar_t argmax_h, scalar_t argmax_w,
+                                             const int h, const int w, const int height, const int width)
+{
+  if (argmax_h <= -1 || argmax_h >= height || argmax_w <= -1 || argmax_w >= width)
+  {
+    //empty
+    return 0;
+  }
+
+  int argmax_h_low = floor(argmax_h);
+  int argmax_w_low = floor(argmax_w);
+  int argmax_h_high = argmax_h_low + 1;
+  int argmax_w_high = argmax_w_low + 1;
+
+  scalar_t weight = 0;
+  if (h == argmax_h_low && w == argmax_w_low)
+    weight = (h + 1 - argmax_h) * (w + 1 - argmax_w);
+  if (h == argmax_h_low && w == argmax_w_high)
+    weight = (h + 1 - argmax_h) * (argmax_w + 1 - w);
+  if (h == argmax_h_high && w == argmax_w_low)
+    weight = (argmax_h + 1 - h) * (w + 1 - argmax_w);
+  if (h == argmax_h_high && w == argmax_w_high)
+    weight = (argmax_h + 1 - h) * (argmax_w + 1 - w);
+  return weight;
+}
+
+template <typename scalar_t>
+__device__ scalar_t dmcn_get_coordinate_weight(scalar_t argmax_h, scalar_t argmax_w,
+                                               const int height, const int width, const scalar_t *im_data,
+                                               const int data_width, const int bp_dir)
+{
+  if (argmax_h <= -1 || argmax_h >= height || argmax_w <= -1 || argmax_w >= width)
+  {
+    //empty
+    return 0;
+  }
+
+  int argmax_h_low = floor(argmax_h);
+  int argmax_w_low = floor(argmax_w);
+  int argmax_h_high = argmax_h_low + 1;
+  int argmax_w_high = argmax_w_low + 1;
+
+  scalar_t weight = 0;
+
+  if (bp_dir == 0)
+  {
+    if (argmax_h_low >= 0 && argmax_w_low >= 0)
+      weight += -1 * (argmax_w_low + 1 - argmax_w) * im_data[argmax_h_low * data_width + argmax_w_low];
+    if (argmax_h_low >= 0 && argmax_w_high <= width - 1)
+      weight += -1 * (argmax_w - argmax_w_low) * im_data[argmax_h_low * data_width + argmax_w_high];
+    if (argmax_h_high <= height - 1 && argmax_w_low >= 0)
+      weight += (argmax_w_low + 1 - argmax_w) * im_data[argmax_h_high * data_width + argmax_w_low];
+    if (argmax_h_high <= height - 1 && argmax_w_high <= width - 1)
+      weight += (argmax_w - argmax_w_low) * im_data[argmax_h_high * data_width + argmax_w_high];
+  }
+  else if (bp_dir == 1)
+  {
+    if (argmax_h_low >= 0 && argmax_w_low >= 0)
+      weight += -1 * (argmax_h_low + 1 - argmax_h) * im_data[argmax_h_low * data_width + argmax_w_low];
+    if (argmax_h_low >= 0 && argmax_w_high <= width - 1)
+      weight += (argmax_h_low + 1 - argmax_h) * im_data[argmax_h_low * data_width + argmax_w_high];
+    if (argmax_h_high <= height - 1 && argmax_w_low >= 0)
+      weight += -1 * (argmax_h - argmax_h_low) * im_data[argmax_h_high * data_width + argmax_w_low];
+    if (argmax_h_high <= height - 1 && argmax_w_high <= width - 1)
+      weight += (argmax_h - argmax_h_low) * im_data[argmax_h_high * data_width + argmax_w_high];
+  }
+
+  return weight;
+}
+
+template <typename scalar_t>
+__global__ void modulated_deformable_im2col_gpu_kernel(const int n,
+                                                       const scalar_t *data_im, const scalar_t *data_offset, const scalar_t *data_mask,
+                                                       const int height, const int width, const int kernel_h, const int kernel_w,
+                                                       const int pad_h, const int pad_w,
+                                                       const int stride_h, const int stride_w,
+                                                       const int dilation_h, const int dilation_w,
+                                                       const int channel_per_deformable_group,
+                                                       const int batch_size, const int num_channels, const int deformable_group,
+                                                       const int height_col, const int width_col,
+                                                       scalar_t *data_col)
+{
+  CUDA_KERNEL_LOOP(index, n)
+  {
+    // index index of output matrix
+    const int w_col = index % width_col;
+    const int h_col = (index / width_col) % height_col;
+    const int b_col = (index / width_col / height_col) % batch_size;
+    const int c_im = (index / width_col / height_col) / batch_size;
+    const int c_col = c_im * kernel_h * kernel_w;
+
+    // compute deformable group index
+    const int deformable_group_index = c_im / channel_per_deformable_group;
+
+    const int h_in = h_col * stride_h - pad_h;
+    const int w_in = w_col * stride_w - pad_w;
+
+    scalar_t *data_col_ptr = data_col + ((c_col * batch_size + b_col) * height_col + h_col) * width_col + w_col;
+    //const float* data_im_ptr = data_im + ((b_col * num_channels + c_im) * height + h_in) * width + w_in;
+    const scalar_t *data_im_ptr = data_im + (b_col * num_channels + c_im) * height * width;
+    const scalar_t *data_offset_ptr = data_offset + (b_col * deformable_group + deformable_group_index) * 2 * kernel_h * kernel_w * height_col * width_col;
+
+    const scalar_t *data_mask_ptr = data_mask + (b_col * deformable_group + deformable_group_index) * kernel_h * kernel_w * height_col * width_col;
+
+    for (int i = 0; i < kernel_h; ++i)
+    {
+      for (int j = 0; j < kernel_w; ++j)
+      {
+        const int data_offset_h_ptr = ((2 * (i * kernel_w + j)) * height_col + h_col) * width_col + w_col;
+        const int data_offset_w_ptr = ((2 * (i * kernel_w + j) + 1) * height_col + h_col) * width_col + w_col;
+        const int data_mask_hw_ptr = ((i * kernel_w + j) * height_col + h_col) * width_col + w_col;
+        const scalar_t offset_h = data_offset_ptr[data_offset_h_ptr];
+        const scalar_t offset_w = data_offset_ptr[data_offset_w_ptr];
+        const scalar_t mask = data_mask_ptr[data_mask_hw_ptr];
+        scalar_t val = static_cast<scalar_t>(0);
+        const scalar_t h_im = h_in + i * dilation_h + offset_h;
+        const scalar_t w_im = w_in + j * dilation_w + offset_w;
+        //if (h_im >= 0 && w_im >= 0 && h_im < height && w_im < width) {
+        if (h_im > -1 && w_im > -1 && h_im < height && w_im < width)
+        {
+          //const float map_h = i * dilation_h + offset_h;
+          //const float map_w = j * dilation_w + offset_w;
+          //const int cur_height = height - h_in;
+          //const int cur_width = width - w_in;
+          //val = dmcn_im2col_bilinear(data_im_ptr, width, cur_height, cur_width, map_h, map_w);
+          val = dmcn_im2col_bilinear(data_im_ptr, width, height, width, h_im, w_im);
+        }
+        *data_col_ptr = val * mask;
+        data_col_ptr += batch_size * height_col * width_col;
+        //data_col_ptr += height_col * width_col;
+      }
+    }
+  }
+}
+
+template <typename scalar_t>
+__global__ void modulated_deformable_col2im_gpu_kernel(const int n,
+                                                       const scalar_t *data_col, const scalar_t *data_offset, const scalar_t *data_mask,
+                                                       const int channels, const int height, const int width,
+                                                       const int kernel_h, const int kernel_w,
+                                                       const int pad_h, const int pad_w,
+                                                       const int stride_h, const int stride_w,
+                                                       const int dilation_h, const int dilation_w,
+                                                       const int channel_per_deformable_group,
+                                                       const int batch_size, const int deformable_group,
+                                                       const int height_col, const int width_col,
+                                                       scalar_t *grad_im)
+{
+  CUDA_KERNEL_LOOP(index, n)
+  {
+    const int j = (index / width_col / height_col / batch_size) % kernel_w;
+    const int i = (index / width_col / height_col / batch_size / kernel_w) % kernel_h;
+    const int c = index / width_col / height_col / batch_size / kernel_w / kernel_h;
+    // compute the start and end of the output
+
+    const int deformable_group_index = c / channel_per_deformable_group;
+
+    int w_out = index % width_col;
+    int h_out = (index / width_col) % height_col;
+    int b = (index / width_col / height_col) % batch_size;
+    int w_in = w_out * stride_w - pad_w;
+    int h_in = h_out * stride_h - pad_h;
+
+    const scalar_t *data_offset_ptr = data_offset + (b * deformable_group + deformable_group_index) * 2 * kernel_h * kernel_w * height_col * width_col;
+    const scalar_t *data_mask_ptr = data_mask + (b * deformable_group + deformable_group_index) * kernel_h * kernel_w * height_col * width_col;
+    const int data_offset_h_ptr = ((2 * (i * kernel_w + j)) * height_col + h_out) * width_col + w_out;
+    const int data_offset_w_ptr = ((2 * (i * kernel_w + j) + 1) * height_col + h_out) * width_col + w_out;
+    const int data_mask_hw_ptr = ((i * kernel_w + j) * height_col + h_out) * width_col + w_out;
+    const scalar_t offset_h = data_offset_ptr[data_offset_h_ptr];
+    const scalar_t offset_w = data_offset_ptr[data_offset_w_ptr];
+    const scalar_t mask = data_mask_ptr[data_mask_hw_ptr];
+    const scalar_t cur_inv_h_data = h_in + i * dilation_h + offset_h;
+    const scalar_t cur_inv_w_data = w_in + j * dilation_w + offset_w;
+
+    const scalar_t cur_top_grad = data_col[index] * mask;
+    const int cur_h = (int)cur_inv_h_data;
+    const int cur_w = (int)cur_inv_w_data;
+    for (int dy = -2; dy <= 2; dy++)
+    {
+      for (int dx = -2; dx <= 2; dx++)
+      {
+        if (cur_h + dy >= 0 && cur_h + dy < height &&
+            cur_w + dx >= 0 && cur_w + dx < width &&
+            abs(cur_inv_h_data - (cur_h + dy)) < 1 &&
+            abs(cur_inv_w_data - (cur_w + dx)) < 1)
+        {
+          int cur_bottom_grad_pos = ((b * channels + c) * height + cur_h + dy) * width + cur_w + dx;
+          scalar_t weight = dmcn_get_gradient_weight(cur_inv_h_data, cur_inv_w_data, cur_h + dy, cur_w + dx, height, width);
+          atomicAdd(grad_im + cur_bottom_grad_pos, weight * cur_top_grad);
+        }
+      }
+    }
+  }
+}
+
+template <typename scalar_t>
+__global__ void modulated_deformable_col2im_coord_gpu_kernel(const int n,
+                                                             const scalar_t *data_col, const scalar_t *data_im,
+                                                             const scalar_t *data_offset, const scalar_t *data_mask,
+                                                             const int channels, const int height, const int width,
+                                                             const int kernel_h, const int kernel_w,
+                                                             const int pad_h, const int pad_w,
+                                                             const int stride_h, const int stride_w,
+                                                             const int dilation_h, const int dilation_w,
+                                                             const int channel_per_deformable_group,
+                                                             const int batch_size, const int offset_channels, const int deformable_group,
+                                                             const int height_col, const int width_col,
+                                                             scalar_t *grad_offset, scalar_t *grad_mask)
+{
+  CUDA_KERNEL_LOOP(index, n)
+  {
+    scalar_t val = 0, mval = 0;
+    int w = index % width_col;
+    int h = (index / width_col) % height_col;
+    int c = (index / width_col / height_col) % offset_channels;
+    int b = (index / width_col / height_col) / offset_channels;
+    // compute the start and end of the output
+
+    const int deformable_group_index = c / (2 * kernel_h * kernel_w);
+    const int col_step = kernel_h * kernel_w;
+    int cnt = 0;
+    const scalar_t *data_col_ptr = data_col + deformable_group_index * channel_per_deformable_group * batch_size * width_col * height_col;
+    const scalar_t *data_im_ptr = data_im + (b * deformable_group + deformable_group_index) * channel_per_deformable_group / kernel_h / kernel_w * height * width;
+    const scalar_t *data_offset_ptr = data_offset + (b * deformable_group + deformable_group_index) * 2 * kernel_h * kernel_w * height_col * width_col;
+    const scalar_t *data_mask_ptr = data_mask + (b * deformable_group + deformable_group_index) * kernel_h * kernel_w * height_col * width_col;
+
+    const int offset_c = c - deformable_group_index * 2 * kernel_h * kernel_w;
+
+    for (int col_c = (offset_c / 2); col_c < channel_per_deformable_group; col_c += col_step)
+    {
+      const int col_pos = (((col_c * batch_size + b) * height_col) + h) * width_col + w;
+      const int bp_dir = offset_c % 2;
+
+      int j = (col_pos / width_col / height_col / batch_size) % kernel_w;
+      int i = (col_pos / width_col / height_col / batch_size / kernel_w) % kernel_h;
+      int w_out = col_pos % width_col;
+      int h_out = (col_pos / width_col) % height_col;
+      int w_in = w_out * stride_w - pad_w;
+      int h_in = h_out * stride_h - pad_h;
+      const int data_offset_h_ptr = (((2 * (i * kernel_w + j)) * height_col + h_out) * width_col + w_out);
+      const int data_offset_w_ptr = (((2 * (i * kernel_w + j) + 1) * height_col + h_out) * width_col + w_out);
+      const int data_mask_hw_ptr = (((i * kernel_w + j) * height_col + h_out) * width_col + w_out);
+      const scalar_t offset_h = data_offset_ptr[data_offset_h_ptr];
+      const scalar_t offset_w = data_offset_ptr[data_offset_w_ptr];
+      const scalar_t mask = data_mask_ptr[data_mask_hw_ptr];
+      scalar_t inv_h = h_in + i * dilation_h + offset_h;
+      scalar_t inv_w = w_in + j * dilation_w + offset_w;
+      if (inv_h <= -1 || inv_w <= -1 || inv_h >= height || inv_w >= width)
+      {
+        inv_h = inv_w = -2;
+      }
+      else
+      {
+        mval += data_col_ptr[col_pos] * dmcn_im2col_bilinear(data_im_ptr + cnt * height * width, width, height, width, inv_h, inv_w);
+      }
+      const scalar_t weight = dmcn_get_coordinate_weight(
+          inv_h, inv_w,
+          height, width, data_im_ptr + cnt * height * width, width, bp_dir);
+      val += weight * data_col_ptr[col_pos] * mask;
+      cnt += 1;
+    }
+    // KERNEL_ASSIGN(grad_offset[index], offset_req, val);
+    grad_offset[index] = val;
+    if (offset_c % 2 == 0)
+      // KERNEL_ASSIGN(grad_mask[(((b * deformable_group + deformable_group_index) * kernel_h * kernel_w + offset_c / 2) * height_col + h) * width_col + w], mask_req, mval);
+      grad_mask[(((b * deformable_group + deformable_group_index) * kernel_h * kernel_w + offset_c / 2) * height_col + h) * width_col + w] = mval;
+  }
+}
+
+void modulated_deformable_im2col_cuda(
+    const at::Tensor data_im, const at::Tensor data_offset, const at::Tensor data_mask,
+    const int batch_size, const int channels, const int height_im, const int width_im,
+    const int height_col, const int width_col, const int kernel_h, const int kenerl_w,
+    const int pad_h, const int pad_w, const int stride_h, const int stride_w,
+    const int dilation_h, const int dilation_w,
+    const int deformable_group, at::Tensor data_col)
+{
+  // num_axes should be smaller than block size
+  const int channel_per_deformable_group = channels / deformable_group;
+  const int num_kernels = channels * batch_size * height_col * width_col;
+
+  AT_DISPATCH_FLOATING_TYPES_AND_HALF(
+      data_im.scalar_type(), "modulated_deformable_im2col_gpu", ([&] {
+        const scalar_t *data_im_ = data_im.data_ptr<scalar_t>();
+        const scalar_t *data_offset_ = data_offset.data_ptr<scalar_t>();
+        const scalar_t *data_mask_ = data_mask.data_ptr<scalar_t>();
+        scalar_t *data_col_ = data_col.data_ptr<scalar_t>();
+
+        modulated_deformable_im2col_gpu_kernel<<<GET_BLOCKS(num_kernels), CUDA_NUM_THREADS, 0, at::cuda::getCurrentCUDAStream()>>>(
+            num_kernels, data_im_, data_offset_, data_mask_, height_im, width_im, kernel_h, kenerl_w,
+            pad_h, pad_w, stride_h, stride_w, dilation_h, dilation_w, channel_per_deformable_group,
+            batch_size, channels, deformable_group, height_col, width_col, data_col_);
+      }));
+
+  cudaError_t err = cudaGetLastError();
+  if (err != cudaSuccess)
+  {
+    printf("error in modulated_deformable_im2col_cuda: %s\n", cudaGetErrorString(err));
+  }
+}
+
+void modulated_deformable_col2im_cuda(
+    const at::Tensor data_col, const at::Tensor data_offset, const at::Tensor data_mask,
+    const int batch_size, const int channels, const int height_im, const int width_im,
+    const int height_col, const int width_col, const int kernel_h, const int kernel_w,
+    const int pad_h, const int pad_w, const int stride_h, const int stride_w,
+    const int dilation_h, const int dilation_w,
+    const int deformable_group, at::Tensor grad_im)
+{
+
+  const int channel_per_deformable_group = channels / deformable_group;
+  const int num_kernels = channels * kernel_h * kernel_w * batch_size * height_col * width_col;
+
+  AT_DISPATCH_FLOATING_TYPES_AND_HALF(
+      data_col.scalar_type(), "modulated_deformable_col2im_gpu", ([&] {
+        const scalar_t *data_col_ = data_col.data_ptr<scalar_t>();
+        const scalar_t *data_offset_ = data_offset.data_ptr<scalar_t>();
+        const scalar_t *data_mask_ = data_mask.data_ptr<scalar_t>();
+        scalar_t *grad_im_ = grad_im.data_ptr<scalar_t>();
+
+        modulated_deformable_col2im_gpu_kernel<<<GET_BLOCKS(num_kernels), CUDA_NUM_THREADS, 0, at::cuda::getCurrentCUDAStream()>>>(
+            num_kernels, data_col_, data_offset_, data_mask_, channels, height_im, width_im,
+            kernel_h, kernel_w, pad_h, pad_w, stride_h, stride_w,
+            dilation_h, dilation_w, channel_per_deformable_group,
+            batch_size, deformable_group, height_col, width_col, grad_im_);
+      }));
+
+  cudaError_t err = cudaGetLastError();
+  if (err != cudaSuccess)
+  {
+    printf("error in modulated_deformable_col2im_cuda: %s\n", cudaGetErrorString(err));
+  }
+}
+
+void modulated_deformable_col2im_coord_cuda(
+    const at::Tensor data_col, const at::Tensor data_im, const at::Tensor data_offset, const at::Tensor data_mask,
+    const int batch_size, const int channels, const int height_im, const int width_im,
+    const int height_col, const int width_col, const int kernel_h, const int kernel_w,
+    const int pad_h, const int pad_w, const int stride_h, const int stride_w,
+    const int dilation_h, const int dilation_w,
+    const int deformable_group,
+    at::Tensor grad_offset, at::Tensor grad_mask)
+{
+  const int num_kernels = batch_size * height_col * width_col * 2 * kernel_h * kernel_w * deformable_group;
+  const int channel_per_deformable_group = channels * kernel_h * kernel_w / deformable_group;
+
+  AT_DISPATCH_FLOATING_TYPES_AND_HALF(
+      data_col.scalar_type(), "modulated_deformable_col2im_coord_gpu", ([&] {
+        const scalar_t *data_col_ = data_col.data_ptr<scalar_t>();
+        const scalar_t *data_im_ = data_im.data_ptr<scalar_t>();
+        const scalar_t *data_offset_ = data_offset.data_ptr<scalar_t>();
+        const scalar_t *data_mask_ = data_mask.data_ptr<scalar_t>();
+        scalar_t *grad_offset_ = grad_offset.data_ptr<scalar_t>();
+        scalar_t *grad_mask_ = grad_mask.data_ptr<scalar_t>();
+
+        modulated_deformable_col2im_coord_gpu_kernel<<<GET_BLOCKS(num_kernels), CUDA_NUM_THREADS, 0, at::cuda::getCurrentCUDAStream()>>>(
+            num_kernels, data_col_, data_im_, data_offset_, data_mask_, channels, height_im, width_im,
+            kernel_h, kernel_w, pad_h, pad_w, stride_h, stride_w,
+            dilation_h, dilation_w, channel_per_deformable_group,
+            batch_size, 2 * kernel_h * kernel_w * deformable_group, deformable_group, height_col, width_col,
+            grad_offset_, grad_mask_);
+      }));
+  cudaError_t err = cudaGetLastError();
+  if (err != cudaSuccess)
+  {
+    printf("error in modulated_deformable_col2im_coord_cuda: %s\n", cudaGetErrorString(err));
+  }
+}

basicsr/ops/dcn/src/deform_conv_ext.cpp

@@ -0,0 +1,164 @@
+// modify from
+// https://github.com/chengdazhi/Deformable-Convolution-V2-PyTorch/blob/mmdetection/mmdet/ops/dcn/src/deform_conv_cuda.c
+
+#include <torch/extension.h>
+#include <ATen/DeviceGuard.h>
+
+#include <cmath>
+#include <vector>
+
+#define WITH_CUDA  // always use cuda
+#ifdef WITH_CUDA
+int deform_conv_forward_cuda(at::Tensor input, at::Tensor weight,
+                             at::Tensor offset, at::Tensor output,
+                             at::Tensor columns, at::Tensor ones, int kW,
+                             int kH, int dW, int dH, int padW, int padH,
+                             int dilationW, int dilationH, int group,
+                             int deformable_group, int im2col_step);
+
+int deform_conv_backward_input_cuda(at::Tensor input, at::Tensor offset,
+                                    at::Tensor gradOutput, at::Tensor gradInput,
+                                    at::Tensor gradOffset, at::Tensor weight,
+                                    at::Tensor columns, int kW, int kH, int dW,
+                                    int dH, int padW, int padH, int dilationW,
+                                    int dilationH, int group,
+                                    int deformable_group, int im2col_step);
+
+int deform_conv_backward_parameters_cuda(
+    at::Tensor input, at::Tensor offset, at::Tensor gradOutput,
+    at::Tensor gradWeight,  // at::Tensor gradBias,
+    at::Tensor columns, at::Tensor ones, int kW, int kH, int dW, int dH,
+    int padW, int padH, int dilationW, int dilationH, int group,
+    int deformable_group, float scale, int im2col_step);
+
+void modulated_deform_conv_cuda_forward(
+    at::Tensor input, at::Tensor weight, at::Tensor bias, at::Tensor ones,
+    at::Tensor offset, at::Tensor mask, at::Tensor output, at::Tensor columns,
+    int kernel_h, int kernel_w, const int stride_h, const int stride_w,
+    const int pad_h, const int pad_w, const int dilation_h,
+    const int dilation_w, const int group, const int deformable_group,
+    const bool with_bias);
+
+void modulated_deform_conv_cuda_backward(
+    at::Tensor input, at::Tensor weight, at::Tensor bias, at::Tensor ones,
+    at::Tensor offset, at::Tensor mask, at::Tensor columns,
+    at::Tensor grad_input, at::Tensor grad_weight, at::Tensor grad_bias,
+    at::Tensor grad_offset, at::Tensor grad_mask, at::Tensor grad_output,
+    int kernel_h, int kernel_w, int stride_h, int stride_w, int pad_h,
+    int pad_w, int dilation_h, int dilation_w, int group, int deformable_group,
+    const bool with_bias);
+#endif
+
+int deform_conv_forward(at::Tensor input, at::Tensor weight,
+                             at::Tensor offset, at::Tensor output,
+                             at::Tensor columns, at::Tensor ones, int kW,
+                             int kH, int dW, int dH, int padW, int padH,
+                             int dilationW, int dilationH, int group,
+                             int deformable_group, int im2col_step) {
+  if (input.device().is_cuda()) {
+#ifdef WITH_CUDA
+    return deform_conv_forward_cuda(input, weight, offset, output, columns,
+        ones, kW, kH, dW, dH, padW, padH, dilationW, dilationH, group,
+        deformable_group, im2col_step);
+#else
+    AT_ERROR("deform conv is not compiled with GPU support");
+#endif
+  }
+  AT_ERROR("deform conv is not implemented on CPU");
+}
+
+int deform_conv_backward_input(at::Tensor input, at::Tensor offset,
+                                    at::Tensor gradOutput, at::Tensor gradInput,
+                                    at::Tensor gradOffset, at::Tensor weight,
+                                    at::Tensor columns, int kW, int kH, int dW,
+                                    int dH, int padW, int padH, int dilationW,
+                                    int dilationH, int group,
+                                    int deformable_group, int im2col_step) {
+  if (input.device().is_cuda()) {
+#ifdef WITH_CUDA
+    return deform_conv_backward_input_cuda(input, offset, gradOutput,
+        gradInput, gradOffset, weight, columns, kW, kH, dW, dH, padW, padH,
+        dilationW, dilationH, group, deformable_group, im2col_step);
+#else
+    AT_ERROR("deform conv is not compiled with GPU support");
+#endif
+  }
+  AT_ERROR("deform conv is not implemented on CPU");
+}
+
+int deform_conv_backward_parameters(
+    at::Tensor input, at::Tensor offset, at::Tensor gradOutput,
+    at::Tensor gradWeight,  // at::Tensor gradBias,
+    at::Tensor columns, at::Tensor ones, int kW, int kH, int dW, int dH,
+    int padW, int padH, int dilationW, int dilationH, int group,
+    int deformable_group, float scale, int im2col_step) {
+  if (input.device().is_cuda()) {
+#ifdef WITH_CUDA
+    return deform_conv_backward_parameters_cuda(input, offset, gradOutput,
+        gradWeight, columns, ones, kW, kH, dW, dH, padW, padH, dilationW,
+        dilationH, group, deformable_group, scale, im2col_step);
+#else
+    AT_ERROR("deform conv is not compiled with GPU support");
+#endif
+  }
+  AT_ERROR("deform conv is not implemented on CPU");
+}
+
+void modulated_deform_conv_forward(
+    at::Tensor input, at::Tensor weight, at::Tensor bias, at::Tensor ones,
+    at::Tensor offset, at::Tensor mask, at::Tensor output, at::Tensor columns,
+    int kernel_h, int kernel_w, const int stride_h, const int stride_w,
+    const int pad_h, const int pad_w, const int dilation_h,
+    const int dilation_w, const int group, const int deformable_group,
+    const bool with_bias) {
+  if (input.device().is_cuda()) {
+#ifdef WITH_CUDA
+    return modulated_deform_conv_cuda_forward(input, weight, bias, ones,
+        offset, mask, output, columns, kernel_h, kernel_w, stride_h,
+        stride_w, pad_h, pad_w, dilation_h, dilation_w, group,
+        deformable_group, with_bias);
+#else
+    AT_ERROR("modulated deform conv is not compiled with GPU support");
+#endif
+  }
+  AT_ERROR("modulated deform conv is not implemented on CPU");
+}
+
+void modulated_deform_conv_backward(
+    at::Tensor input, at::Tensor weight, at::Tensor bias, at::Tensor ones,
+    at::Tensor offset, at::Tensor mask, at::Tensor columns,
+    at::Tensor grad_input, at::Tensor grad_weight, at::Tensor grad_bias,
+    at::Tensor grad_offset, at::Tensor grad_mask, at::Tensor grad_output,
+    int kernel_h, int kernel_w, int stride_h, int stride_w, int pad_h,
+    int pad_w, int dilation_h, int dilation_w, int group, int deformable_group,
+    const bool with_bias) {
+  if (input.device().is_cuda()) {
+#ifdef WITH_CUDA
+    return modulated_deform_conv_cuda_backward(input, weight, bias, ones,
+        offset, mask, columns, grad_input, grad_weight, grad_bias, grad_offset,
+        grad_mask, grad_output, kernel_h, kernel_w, stride_h, stride_w,
+        pad_h, pad_w, dilation_h, dilation_w, group, deformable_group,
+        with_bias);
+#else
+    AT_ERROR("modulated deform conv is not compiled with GPU support");
+#endif
+  }
+  AT_ERROR("modulated deform conv is not implemented on CPU");
+}
+
+
+PYBIND11_MODULE(TORCH_EXTENSION_NAME, m) {
+  m.def("deform_conv_forward", &deform_conv_forward,
+        "deform forward");
+  m.def("deform_conv_backward_input", &deform_conv_backward_input,
+        "deform_conv_backward_input");
+  m.def("deform_conv_backward_parameters",
+        &deform_conv_backward_parameters,
+        "deform_conv_backward_parameters");
+  m.def("modulated_deform_conv_forward",
+        &modulated_deform_conv_forward,
+        "modulated deform conv forward");
+  m.def("modulated_deform_conv_backward",
+        &modulated_deform_conv_backward,
+        "modulated deform conv backward");
+}

basicsr/ops/fused_act/__init__.py

@@ -0,0 +1,3 @@
+from .fused_act import FusedLeakyReLU, fused_leaky_relu
+
+__all__ = ['FusedLeakyReLU', 'fused_leaky_relu']

basicsr/ops/fused_act/fused_act.py

@@ -0,0 +1,89 @@
+# modify from https://github.com/rosinality/stylegan2-pytorch/blob/master/op/fused_act.py # noqa:E501
+
+import torch
+from torch import nn
+from torch.autograd import Function
+
+try:
+    from . import fused_act_ext
+except ImportError:
+    import os
+    BASICSR_JIT = os.getenv('BASICSR_JIT')
+    if BASICSR_JIT == 'True':
+        from torch.utils.cpp_extension import load
+        module_path = os.path.dirname(__file__)
+        fused_act_ext = load(
+            'fused',
+            sources=[
+                os.path.join(module_path, 'src', 'fused_bias_act.cpp'),
+                os.path.join(module_path, 'src', 'fused_bias_act_kernel.cu'),
+            ],
+        )
+
+
+class FusedLeakyReLUFunctionBackward(Function):
+
+    @staticmethod
+    def forward(ctx, grad_output, out, negative_slope, scale):
+        ctx.save_for_backward(out)
+        ctx.negative_slope = negative_slope
+        ctx.scale = scale
+
+        empty = grad_output.new_empty(0)
+
+        grad_input = fused_act_ext.fused_bias_act(grad_output, empty, out, 3, 1, negative_slope, scale)
+
+        dim = [0]
+
+        if grad_input.ndim > 2:
+            dim += list(range(2, grad_input.ndim))
+
+        grad_bias = grad_input.sum(dim).detach()
+
+        return grad_input, grad_bias
+
+    @staticmethod
+    def backward(ctx, gradgrad_input, gradgrad_bias):
+        out, = ctx.saved_tensors
+        gradgrad_out = fused_act_ext.fused_bias_act(gradgrad_input, gradgrad_bias, out, 3, 1, ctx.negative_slope,
+                                                    ctx.scale)
+
+        return gradgrad_out, None, None, None
+
+
+class FusedLeakyReLUFunction(Function):
+
+    @staticmethod
+    def forward(ctx, input, bias, negative_slope, scale):
+        empty = input.new_empty(0)
+        out = fused_act_ext.fused_bias_act(input, bias, empty, 3, 0, negative_slope, scale)
+        ctx.save_for_backward(out)
+        ctx.negative_slope = negative_slope
+        ctx.scale = scale
+
+        return out
+
+    @staticmethod
+    def backward(ctx, grad_output):
+        out, = ctx.saved_tensors
+
+        grad_input, grad_bias = FusedLeakyReLUFunctionBackward.apply(grad_output, out, ctx.negative_slope, ctx.scale)
+
+        return grad_input, grad_bias, None, None
+
+
+class FusedLeakyReLU(nn.Module):
+
+    def __init__(self, channel, negative_slope=0.2, scale=2**0.5):
+        super().__init__()
+
+        self.bias = nn.Parameter(torch.zeros(channel))
+        self.negative_slope = negative_slope
+        self.scale = scale
+
+    def forward(self, input):
+        return fused_leaky_relu(input, self.bias, self.negative_slope, self.scale)
+
+
+def fused_leaky_relu(input, bias, negative_slope=0.2, scale=2**0.5):
+    return FusedLeakyReLUFunction.apply(input, bias, negative_slope, scale)

basicsr/ops/fused_act/src/fused_bias_act.cpp

@@ -0,0 +1,26 @@
+// from https://github.com/rosinality/stylegan2-pytorch/blob/master/op/fused_bias_act.cpp
+#include <torch/extension.h>
+
+
+torch::Tensor fused_bias_act_op(const torch::Tensor& input,
+                                const torch::Tensor& bias,
+                                const torch::Tensor& refer,
+                                int act, int grad, float alpha, float scale);
+
+#define CHECK_CUDA(x) TORCH_CHECK(x.type().is_cuda(), #x " must be a CUDA tensor")
+#define CHECK_CONTIGUOUS(x) TORCH_CHECK(x.is_contiguous(), #x " must be contiguous")
+#define CHECK_INPUT(x) CHECK_CUDA(x); CHECK_CONTIGUOUS(x)
+
+torch::Tensor fused_bias_act(const torch::Tensor& input,
+                             const torch::Tensor& bias,
+                             const torch::Tensor& refer,
+                             int act, int grad, float alpha, float scale) {
+    CHECK_CUDA(input);
+    CHECK_CUDA(bias);
+
+    return fused_bias_act_op(input, bias, refer, act, grad, alpha, scale);
+}
+
+PYBIND11_MODULE(TORCH_EXTENSION_NAME, m) {
+    m.def("fused_bias_act", &fused_bias_act, "fused bias act (CUDA)");
+}