add: detailed dataset card.

README.md

@@ -42,6 +42,7 @@ dataset_info:
   - [Data Instances](#data-instances)
   - [Data Fields](#data-fields)
   - [Data Splits](#data-splits)
+- [Visualization](#visualization)
 - [Dataset Creation](#dataset-creation)
   - [Curation Rationale](#curation-rationale)
   - [Source Data](#source-data)
@@ -62,7 +63,7 @@ dataset_info:
 
 - **Homepage:** [NYU Depth Dataset V2 homepage](https://cs.nyu.edu/~silberman/datasets/nyu_depth_v2.html)
 - **Repository:** Fast Depth [repository](https://github.com/dwofk/fast-depth) which was used to source the dataset in this repository. It is a preprocessed version of the original NYU Depth V2 dataset linked above. It is also used in [TensorFlow Datasets](https://www.tensorflow.org/datasets/catalog/nyu_depth_v2).
-- **Paper:** [Indoor Segmentation and Support Inference from RGBD Images](http://cs.nyu.edu/~silberman/papers/indoor_seg_support.pdf) and [FastDepth: Fast Monocular Depth Estimation on Embedded Systems](https://arxiv.org/abs/1903.03273)
+- **Papers:** [Indoor Segmentation and Support Inference from RGBD Images](http://cs.nyu.edu/~silberman/papers/indoor_seg_support.pdf) and [FastDepth: Fast Monocular Depth Estimation on Embedded Systems](https://arxiv.org/abs/1903.03273)
 - **Point of Contact:** [Nathan Silberman](mailto:silberman@@cs.nyu.edu) and [Diana Wofk](mailto:dwofk@alum.mit.edu)
 
 ### Dataset Summary
@@ -84,4 +85,163 @@ The dataset has several components:
 
 ### Supported Tasks
 
-- `depth-estimation`: Depth estimation is the task of approximating the perceived depth of a given image. In other words, it's about measuring the distance of each image pixel from the camera.
+- `depth-estimation`: Depth estimation is the task of approximating the perceived depth of a given image. In other words, it's about measuring the distance of each image pixel from the camera.
+
+
+### Languages
+
+English.
+
+## Dataset Structure
+
+### Data Instances
+
+A data point comprises an image and its annotation depth map for both the `train` and `validation` splits. 
+
+```
+{
+  'image': <PIL.JpegImagePlugin.JpegImageFile image mode=RGB at 0x1FF32A3EDA0>,
+  'depth_map': <PIL.PngImagePlugin.PngImageFile image mode=L at 0x1FF32E5B978>,
+}
+```
+
+### Data Fields
+
+- `image`: A `PIL.Image.Image` object containing the image. Note that when accessing the image column: `dataset[0]["image"]` the image file is automatically decoded. Decoding of a large number of image files might take a significant amount of time. Thus it is important to first query the sample index before the `"image"` column, *i.e.* `dataset[0]["image"]` should **always** be preferred over `dataset["image"][0]`.
+- `depth_map`: A `PIL.Image.Image` object containing the annotation depth map.
+
+### Data Splits
+
+The data is split into training, and validation splits. The training data contains 47584 images, and the validation data contains 654 images.
+
+## Visualization
+
+You can use the following code snippet to visualize samples from the dataset:
+
+```py
+from datasets import load_dataset
+import numpy as np
+import matplotlib.pyplot as plt
+
+
+cmap = plt.cm.viridis
+
+ds = load_dataset("sayakpaul/nyu_depth_v2")
+
+
+def colored_depthmap(depth, d_min=None, d_max=None):
+    if d_min is None:
+        d_min = np.min(depth)
+    if d_max is None:
+        d_max = np.max(depth)
+    depth_relative = (depth - d_min) / (d_max - d_min)
+    return 255 * cmap(depth_relative)[:,:,:3] # H, W, C
+
+
+def merge_into_row(input, depth_target):
+    input = np.array(input)
+    depth_target = np.squeeze(np.array(depth_target))
+
+    d_min = np.min(depth_target)
+    d_max = np.max(depth_target)
+    depth_target_col = colored_depthmap(depth_target, d_min, d_max)
+    img_merge = np.hstack([input, depth_target_col])
+    
+    return img_merge
+
+
+random_indices = np.random.choice(len(ds["train"]), 9).tolist()
+train_set = ds["train"]
+
+plt.figure(figsize=(15, 6))
+
+for i, idx in enumerate(random_indices):
+    ax = plt.subplot(3, 3, i + 1)
+    image_viz = merge_into_row(
+        train_set[idx]["image"], train_set[idx]["depth_map"]
+    )
+    plt.imshow(image_viz.astype("uint8"))
+    plt.axis("off")
+```
+
+## Dataset Creation
+
+### Curation Rationale
+
+The rationale from [the paper](http://cs.nyu.edu/~silberman/papers/indoor_seg_support.pdf) that introduced the NYU Depth V2 dataset:
+
+> We present an approach to interpret the major surfaces, objects, and support relations of an indoor scene from an RGBD image. Most existing work ignores physical interactions or is applied only to tidy rooms and hallways. Our goal is to parse typical, often messy, indoor scenes into floor, walls, supporting surfaces, and object regions, and to recover support relationships. One of our main interests is to better understand how 3D cues can best inform a structured 3D interpretation.
+
+### Source Data
+
+#### Initial Data Collection 
+
+> The dataset consists of 1449 RGBD images, gathered from a wide range
+of commercial and residential buildings in three different US cities, comprising
+464 different indoor scenes across 26 scene classes.A dense per-pixel labeling was
+obtained for each image using Amazon Mechanical Turk.
+
+#### Who are the source language producers?
+
+[TODO]
+
+### Annotations
+
+#### Annotation process
+
+This is an involved process. Interested readers are referred to Sections 2, 3, and 4 of the [original paper](http://cs.nyu.edu/~silberman/papers/indoor_seg_support.pdf). 
+
+#### Who are the annotators?
+
+AMT annotators.
+
+### Personal and Sensitive Information
+
+[More Information Needed]
+
+## Considerations for Using the Data
+
+### Social Impact of Dataset
+
+[More Information Needed]
+
+### Discussion of Biases
+
+[More Information Needed]
+
+### Other Known Limitations
+
+[More Information Needed]
+
+## Additional Information
+
+### Dataset Curators
+
+* Original NYU Depth V2 dataset: Nathan Silberman, Derek Hoiem, Pushmeet Kohli, Rob Fergus
+* Preprocessed version: Diana Wofk, Fangchang Ma, Tien-Ju Yang, Sertac Karaman, Vivienne Sze
+
+### Licensing Information
+
+The preprocessed NYU Depth V2 dataset is licensed under a [MIT License](https://github.com/dwofk/fast-depth/blob/master/LICENSE).
+
+### Citation Information
+
+```bibtex
+@inproceedings{Silberman:ECCV12,
+  author    = {Nathan Silberman, Derek Hoiem, Pushmeet Kohli and Rob Fergus},
+  title     = {Indoor Segmentation and Support Inference from RGBD Images},
+  booktitle = {ECCV},
+  year      = {2012}
+}
+
+@inproceedings{icra_2019_fastdepth,
+	author      = {{Wofk, Diana and Ma, Fangchang and Yang, Tien-Ju and Karaman, Sertac and Sze, Vivienne}},
+	title       = {{FastDepth: Fast Monocular Depth Estimation on Embedded Systems}},
+	booktitle   = {{IEEE International Conference on Robotics and Automation (ICRA)}},
+	year        = {{2019}}
+}
+```
+
+### Contributions
+
+Thanks to [@sayakpaul](https://huggingface.co/sayakpaul) for adding this dataset.