Source code for transformers.models.detr.feature_extraction_detr

# coding=utf-8
# Copyright 2021 The HuggingFace Inc. team. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Feature extractor class for DETR."""

import io
import pathlib
from collections import defaultdict
from typing import Dict, List, Optional, Union

import numpy as np
from PIL import Image

from ...feature_extraction_utils import BatchFeature, FeatureExtractionMixin
from ...file_utils import TensorType, is_torch_available
from ...image_utils import ImageFeatureExtractionMixin, is_torch_tensor
from ...utils import logging


if is_torch_available():
    import torch
    from torch import nn

logger = logging.get_logger(__name__)


ImageInput = Union[Image.Image, np.ndarray, "torch.Tensor", List[Image.Image], List[np.ndarray], List["torch.Tensor"]]


# 2 functions below inspired by https://github.com/facebookresearch/detr/blob/master/util/box_ops.py
def center_to_corners_format(x):
    """
    Converts a PyTorch tensor of bounding boxes of center format (center_x, center_y, width, height) to corners format
    (x_0, y_0, x_1, y_1).
    """
    x_c, y_c, w, h = x.unbind(-1)
    b = [(x_c - 0.5 * w), (y_c - 0.5 * h), (x_c + 0.5 * w), (y_c + 0.5 * h)]
    return torch.stack(b, dim=-1)


def corners_to_center_format(x):
    """
    Converts a NumPy array of bounding boxes of shape (number of bounding boxes, 4) of corners format (x_0, y_0, x_1,
    y_1) to center format (center_x, center_y, width, height).
    """
    x_transposed = x.T
    x0, y0, x1, y1 = x_transposed[0], x_transposed[1], x_transposed[2], x_transposed[3]
    b = [(x0 + x1) / 2, (y0 + y1) / 2, (x1 - x0), (y1 - y0)]
    return np.stack(b, axis=-1)


def masks_to_boxes(masks):
    """
    Compute the bounding boxes around the provided panoptic segmentation masks.

    The masks should be in format [N, H, W] where N is the number of masks, (H, W) are the spatial dimensions.

    Returns a [N, 4] tensor, with the boxes in corner (xyxy) format.
    """
    if masks.size == 0:
        return np.zeros((0, 4))

    h, w = masks.shape[-2:]

    y = np.arange(0, h, dtype=np.float32)
    x = np.arange(0, w, dtype=np.float32)
    # see https://github.com/pytorch/pytorch/issues/50276
    y, x = np.meshgrid(y, x, indexing="ij")

    x_mask = masks * np.expand_dims(x, axis=0)
    x_max = x_mask.reshape(x_mask.shape[0], -1).max(-1)
    x = np.ma.array(x_mask, mask=~(np.array(masks, dtype=bool)))
    x_min = x.filled(fill_value=1e8)
    x_min = x_min.reshape(x_min.shape[0], -1).min(-1)

    y_mask = masks * np.expand_dims(y, axis=0)
    y_max = y_mask.reshape(x_mask.shape[0], -1).max(-1)
    y = np.ma.array(y_mask, mask=~(np.array(masks, dtype=bool)))
    y_min = y.filled(fill_value=1e8)
    y_min = y_min.reshape(y_min.shape[0], -1).min(-1)

    return np.stack([x_min, y_min, x_max, y_max], 1)


# 2 functions below copied from https://github.com/cocodataset/panopticapi/blob/master/panopticapi/utils.py
# Copyright (c) 2018, Alexander Kirillov
# All rights reserved.
def rgb_to_id(color):
    if isinstance(color, np.ndarray) and len(color.shape) == 3:
        if color.dtype == np.uint8:
            color = color.astype(np.int32)
        return color[:, :, 0] + 256 * color[:, :, 1] + 256 * 256 * color[:, :, 2]
    return int(color[0] + 256 * color[1] + 256 * 256 * color[2])


def id_to_rgb(id_map):
    if isinstance(id_map, np.ndarray):
        id_map_copy = id_map.copy()
        rgb_shape = tuple(list(id_map.shape) + [3])
        rgb_map = np.zeros(rgb_shape, dtype=np.uint8)
        for i in range(3):
            rgb_map[..., i] = id_map_copy % 256
            id_map_copy //= 256
        return rgb_map
    color = []
    for _ in range(3):
        color.append(id_map % 256)
        id_map //= 256
    return color


[docs]class DetrFeatureExtractor(FeatureExtractionMixin, ImageFeatureExtractionMixin): r""" Constructs a DETR feature extractor. This feature extractor inherits from :class:`~transformers.FeatureExtractionMixin` which contains most of the main methods. Users should refer to this superclass for more information regarding those methods. Args: format (:obj:`str`, `optional`, defaults to :obj:`"coco_detection"`): Data format of the annotations. One of "coco_detection" or "coco_panoptic". do_resize (:obj:`bool`, `optional`, defaults to :obj:`True`): Whether to resize the input to a certain :obj:`size`. size (:obj:`int`, `optional`, defaults to 800): Resize the input to the given size. Only has an effect if :obj:`do_resize` is set to :obj:`True`. If size is a sequence like :obj:`(width, height)`, output size will be matched to this. If size is an int, smaller edge of the image will be matched to this number. i.e, if :obj:`height > width`, then image will be rescaled to :obj:`(size * height / width, size)`. max_size (:obj:`int`, `optional`, defaults to :obj:`1333`): The largest size an image dimension can have (otherwise it's capped). Only has an effect if :obj:`do_resize` is set to :obj:`True`. do_normalize (:obj:`bool`, `optional`, defaults to :obj:`True`): Whether or not to normalize the input with mean and standard deviation. image_mean (:obj:`int`, `optional`, defaults to :obj:`[0.485, 0.456, 0.406]`): The sequence of means for each channel, to be used when normalizing images. Defaults to the ImageNet mean. image_std (:obj:`int`, `optional`, defaults to :obj:`[0.229, 0.224, 0.225]`): The sequence of standard deviations for each channel, to be used when normalizing images. Defaults to the ImageNet std. """ model_input_names = ["pixel_values", "pixel_mask"] def __init__( self, format="coco_detection", do_resize=True, size=800, max_size=1333, do_normalize=True, image_mean=None, image_std=None, **kwargs ): super().__init__(**kwargs) self.format = self._is_valid_format(format) self.do_resize = do_resize self.size = size self.max_size = max_size self.do_normalize = do_normalize self.image_mean = image_mean if image_mean is not None else [0.485, 0.456, 0.406] # ImageNet mean self.image_std = image_std if image_std is not None else [0.229, 0.224, 0.225] # ImageNet std def _is_valid_format(self, format): if format not in ["coco_detection", "coco_panoptic"]: raise ValueError(f"Format {format} not supported") return format def prepare(self, image, target, return_segmentation_masks=False, masks_path=None): if self.format == "coco_detection": image, target = self.prepare_coco_detection(image, target, return_segmentation_masks) return image, target elif self.format == "coco_panoptic": image, target = self.prepare_coco_panoptic(image, target, masks_path) return image, target else: raise ValueError(f"Format {self.format} not supported") # inspired by https://github.com/facebookresearch/detr/blob/master/datasets/coco.py#L33 def convert_coco_poly_to_mask(self, segmentations, height, width): try: from pycocotools import mask as coco_mask except ImportError: raise ImportError("Pycocotools is not installed in your environment.") masks = [] for polygons in segmentations: rles = coco_mask.frPyObjects(polygons, height, width) mask = coco_mask.decode(rles) if len(mask.shape) < 3: mask = mask[..., None] mask = np.asarray(mask, dtype=np.uint8) mask = np.any(mask, axis=2) masks.append(mask) if masks: masks = np.stack(masks, axis=0) else: masks = np.zeros((0, height, width), dtype=np.uint8) return masks # inspired by https://github.com/facebookresearch/detr/blob/master/datasets/coco.py#L50 def prepare_coco_detection(self, image, target, return_segmentation_masks=False): """ Convert the target in COCO format into the format expected by DETR. """ w, h = image.size image_id = target["image_id"] image_id = np.asarray([image_id], dtype=np.int64) # get all COCO annotations for the given image anno = target["annotations"] anno = [obj for obj in anno if "iscrowd" not in obj or obj["iscrowd"] == 0] boxes = [obj["bbox"] for obj in anno] # guard against no boxes via resizing boxes = np.asarray(boxes, dtype=np.float32).reshape(-1, 4) boxes[:, 2:] += boxes[:, :2] boxes[:, 0::2] = boxes[:, 0::2].clip(min=0, max=w) boxes[:, 1::2] = boxes[:, 1::2].clip(min=0, max=h) classes = [obj["category_id"] for obj in anno] classes = np.asarray(classes, dtype=np.int64) if return_segmentation_masks: segmentations = [obj["segmentation"] for obj in anno] masks = self.convert_coco_poly_to_mask(segmentations, h, w) keypoints = None if anno and "keypoints" in anno[0]: keypoints = [obj["keypoints"] for obj in anno] keypoints = np.asarray(keypoints, dtype=np.float32) num_keypoints = keypoints.shape[0] if num_keypoints: keypoints = keypoints.reshape((-1, 3)) keep = (boxes[:, 3] > boxes[:, 1]) & (boxes[:, 2] > boxes[:, 0]) boxes = boxes[keep] classes = classes[keep] if return_segmentation_masks: masks = masks[keep] if keypoints is not None: keypoints = keypoints[keep] target = {} target["boxes"] = boxes target["class_labels"] = classes if return_segmentation_masks: target["masks"] = masks target["image_id"] = image_id if keypoints is not None: target["keypoints"] = keypoints # for conversion to coco api area = np.asarray([obj["area"] for obj in anno], dtype=np.float32) iscrowd = np.asarray([obj["iscrowd"] if "iscrowd" in obj else 0 for obj in anno], dtype=np.int64) target["area"] = area[keep] target["iscrowd"] = iscrowd[keep] target["orig_size"] = np.asarray([int(h), int(w)], dtype=np.int64) target["size"] = np.asarray([int(h), int(w)], dtype=np.int64) return image, target def prepare_coco_panoptic(self, image, target, masks_path, return_masks=True): w, h = image.size ann_info = target.copy() ann_path = pathlib.Path(masks_path) / ann_info["file_name"] if "segments_info" in ann_info: masks = np.asarray(Image.open(ann_path), dtype=np.uint32) masks = rgb_to_id(masks) ids = np.array([ann["id"] for ann in ann_info["segments_info"]]) masks = masks == ids[:, None, None] masks = np.asarray(masks, dtype=np.uint8) labels = np.asarray([ann["category_id"] for ann in ann_info["segments_info"]], dtype=np.int64) target = {} target["image_id"] = np.asarray( [ann_info["image_id"] if "image_id" in ann_info else ann_info["id"]], dtype=np.int64 ) if return_masks: target["masks"] = masks target["class_labels"] = labels target["boxes"] = masks_to_boxes(masks) target["size"] = np.asarray([int(h), int(w)], dtype=np.int64) target["orig_size"] = np.asarray([int(h), int(w)], dtype=np.int64) if "segments_info" in ann_info: target["iscrowd"] = np.asarray([ann["iscrowd"] for ann in ann_info["segments_info"]], dtype=np.int64) target["area"] = np.asarray([ann["area"] for ann in ann_info["segments_info"]], dtype=np.float32) return image, target def _resize(self, image, size, target=None, max_size=None): """ Resize the image to the given size. Size can be min_size (scalar) or (w, h) tuple. If size is an int, smaller edge of the image will be matched to this number. If given, also resize the target accordingly. """ if not isinstance(image, Image.Image): image = self.to_pil_image(image) def get_size_with_aspect_ratio(image_size, size, max_size=None): w, h = image_size if max_size is not None: min_original_size = float(min((w, h))) max_original_size = float(max((w, h))) if max_original_size / min_original_size * size > max_size: size = int(round(max_size * min_original_size / max_original_size)) if (w <= h and w == size) or (h <= w and h == size): return (h, w) if w < h: ow = size oh = int(size * h / w) else: oh = size ow = int(size * w / h) return (oh, ow) def get_size(image_size, size, max_size=None): if isinstance(size, (list, tuple)): return size else: # size returned must be (w, h) since we use PIL to resize images # so we revert the tuple return get_size_with_aspect_ratio(image_size, size, max_size)[::-1] size = get_size(image.size, size, max_size) rescaled_image = self.resize(image, size=size) if target is None: return rescaled_image, None ratios = tuple(float(s) / float(s_orig) for s, s_orig in zip(rescaled_image.size, image.size)) ratio_width, ratio_height = ratios target = target.copy() if "boxes" in target: boxes = target["boxes"] scaled_boxes = boxes * np.asarray([ratio_width, ratio_height, ratio_width, ratio_height], dtype=np.float32) target["boxes"] = scaled_boxes if "area" in target: area = target["area"] scaled_area = area * (ratio_width * ratio_height) target["area"] = scaled_area w, h = size target["size"] = np.asarray([h, w], dtype=np.int64) if "masks" in target: # use PyTorch as current workaround # TODO replace by self.resize masks = torch.from_numpy(target["masks"][:, None]).float() interpolated_masks = nn.functional.interpolate(masks, size=(h, w), mode="nearest")[:, 0] > 0.5 target["masks"] = interpolated_masks.numpy() return rescaled_image, target def _normalize(self, image, mean, std, target=None): """ Normalize the image with a certain mean and std. If given, also normalize the target bounding boxes based on the size of the image. """ image = self.normalize(image, mean=mean, std=std) if target is None: return image, None target = target.copy() h, w = image.shape[-2:] if "boxes" in target: boxes = target["boxes"] boxes = corners_to_center_format(boxes) boxes = boxes / np.asarray([w, h, w, h], dtype=np.float32) target["boxes"] = boxes return image, target
[docs] def __call__( self, images: ImageInput, annotations: Union[List[Dict], List[List[Dict]]] = None, return_segmentation_masks: Optional[bool] = False, masks_path: Optional[pathlib.Path] = None, pad_and_return_pixel_mask: Optional[bool] = True, return_tensors: Optional[Union[str, TensorType]] = None, **kwargs, ) -> BatchFeature: """ Main method to prepare for the model one or several image(s) and optional annotations. Images are by default padded up to the largest image in a batch, and a pixel mask is created that indicates which pixels are real/which are padding. .. warning:: NumPy arrays and PyTorch tensors are converted to PIL images when resizing, so the most efficient is to pass PIL images. Args: images (:obj:`PIL.Image.Image`, :obj:`np.ndarray`, :obj:`torch.Tensor`, :obj:`List[PIL.Image.Image]`, :obj:`List[np.ndarray]`, :obj:`List[torch.Tensor]`): The image or batch of images to be prepared. Each image can be a PIL image, NumPy array or PyTorch tensor. In case of a NumPy array/PyTorch tensor, each image should be of shape (C, H, W), where C is a number of channels, H and W are image height and width. annotations (:obj:`Dict`, :obj:`List[Dict]`, `optional`): The corresponding annotations in COCO format. In case :class:`~transformers.DetrFeatureExtractor` was initialized with :obj:`format = "coco_detection"`, the annotations for each image should have the following format: {'image_id': int, 'annotations': [annotation]}, with the annotations being a list of COCO object annotations. In case :class:`~transformers.DetrFeatureExtractor` was initialized with :obj:`format = "coco_panoptic"`, the annotations for each image should have the following format: {'image_id': int, 'file_name': str, 'segments_info': [segment_info]} with segments_info being a list of COCO panoptic annotations. return_segmentation_masks (:obj:`Dict`, :obj:`List[Dict]`, `optional`, defaults to :obj:`False`): Whether to also include instance segmentation masks as part of the labels in case :obj:`format = "coco_detection"`. masks_path (:obj:`pathlib.Path`, `optional`): Path to the directory containing the PNG files that store the class-agnostic image segmentations. Only relevant in case :class:`~transformers.DetrFeatureExtractor` was initialized with :obj:`format = "coco_panoptic"`. pad_and_return_pixel_mask (:obj:`bool`, `optional`, defaults to :obj:`True`): Whether or not to pad images up to the largest image in a batch and create a pixel mask. If left to the default, will return a pixel mask that is: - 1 for pixels that are real (i.e. **not masked**), - 0 for pixels that are padding (i.e. **masked**). return_tensors (:obj:`str` or :class:`~transformers.file_utils.TensorType`, `optional`): If set, will return tensors instead of NumPy arrays. If set to :obj:`'pt'`, return PyTorch :obj:`torch.Tensor` objects. Returns: :class:`~transformers.BatchFeature`: A :class:`~transformers.BatchFeature` with the following fields: - **pixel_values** -- Pixel values to be fed to a model. - **pixel_mask** -- Pixel mask to be fed to a model (when :obj:`pad_and_return_pixel_mask=True` or if `"pixel_mask"` is in :obj:`self.model_input_names`). - **labels** -- Optional labels to be fed to a model (when :obj:`annotations` are provided) """ # Input type checking for clearer error valid_images = False valid_annotations = False valid_masks_path = False # Check that images has a valid type if isinstance(images, (Image.Image, np.ndarray)) or is_torch_tensor(images): valid_images = True elif isinstance(images, (list, tuple)): if len(images) == 0 or isinstance(images[0], (Image.Image, np.ndarray)) or is_torch_tensor(images[0]): valid_images = True if not valid_images: raise ValueError( "Images must of type `PIL.Image.Image`, `np.ndarray` or `torch.Tensor` (single example)," "`List[PIL.Image.Image]`, `List[np.ndarray]` or `List[torch.Tensor]` (batch of examples)." ) is_batched = bool( isinstance(images, (list, tuple)) and (isinstance(images[0], (Image.Image, np.ndarray)) or is_torch_tensor(images[0])) ) # Check that annotations has a valid type if annotations is not None: if not is_batched: if self.format == "coco_detection": if isinstance(annotations, dict) and "image_id" in annotations and "annotations" in annotations: if isinstance(annotations["annotations"], (list, tuple)): # an image can have no annotations if len(annotations["annotations"]) == 0 or isinstance(annotations["annotations"][0], dict): valid_annotations = True elif self.format == "coco_panoptic": if isinstance(annotations, dict) and "image_id" in annotations and "segments_info" in annotations: if isinstance(annotations["segments_info"], (list, tuple)): # an image can have no segments (?) if len(annotations["segments_info"]) == 0 or isinstance( annotations["segments_info"][0], dict ): valid_annotations = True else: if isinstance(annotations, (list, tuple)): assert len(images) == len(annotations), "There must be as many annotations as there are images" if isinstance(annotations[0], Dict): if self.format == "coco_detection": if isinstance(annotations[0]["annotations"], (list, tuple)): valid_annotations = True elif self.format == "coco_panoptic": if isinstance(annotations[0]["segments_info"], (list, tuple)): valid_annotations = True if not valid_annotations: raise ValueError( """ Annotations must of type `Dict` (single image) or `List[Dict]` (batch of images). In case of object detection, each dictionary should contain the keys 'image_id' and 'annotations', with the latter being a list of annotations in COCO format. In case of panoptic segmentation, each dictionary should contain the keys 'file_name', 'image_id' and 'segments_info', with the latter being a list of annotations in COCO format. """ ) # Check that masks_path has a valid type if masks_path is not None: if self.format == "coco_panoptic": if isinstance(masks_path, pathlib.Path): valid_masks_path = True if not valid_masks_path: raise ValueError( "The path to the directory containing the mask PNG files should be provided as a `pathlib.Path` object." ) if not is_batched: images = [images] if annotations is not None: annotations = [annotations] # prepare (COCO annotations as a list of Dict -> DETR target as a single Dict per image) if annotations is not None: for idx, (image, target) in enumerate(zip(images, annotations)): if not isinstance(image, Image.Image): image = self.to_pil_image(image) image, target = self.prepare(image, target, return_segmentation_masks, masks_path) images[idx] = image annotations[idx] = target # transformations (resizing + normalization) if self.do_resize and self.size is not None: if annotations is not None: for idx, (image, target) in enumerate(zip(images, annotations)): image, target = self._resize(image=image, target=target, size=self.size, max_size=self.max_size) images[idx] = image annotations[idx] = target else: for idx, image in enumerate(images): images[idx] = self._resize(image=image, target=None, size=self.size, max_size=self.max_size)[0] if self.do_normalize: if annotations is not None: for idx, (image, target) in enumerate(zip(images, annotations)): image, target = self._normalize( image=image, mean=self.image_mean, std=self.image_std, target=target ) images[idx] = image annotations[idx] = target else: images = [ self._normalize(image=image, mean=self.image_mean, std=self.image_std)[0] for image in images ] if pad_and_return_pixel_mask: # pad images up to largest image in batch and create pixel_mask max_size = self._max_by_axis([list(image.shape) for image in images]) c, h, w = max_size padded_images = [] pixel_mask = [] for image in images: # create padded image padded_image = np.zeros((c, h, w), dtype=np.float32) padded_image[: image.shape[0], : image.shape[1], : image.shape[2]] = np.copy(image) padded_images.append(padded_image) # create pixel mask mask = np.zeros((h, w), dtype=np.int64) mask[: image.shape[1], : image.shape[2]] = True pixel_mask.append(mask) images = padded_images # return as BatchFeature data = {} data["pixel_values"] = images if pad_and_return_pixel_mask: data["pixel_mask"] = pixel_mask encoded_inputs = BatchFeature(data=data, tensor_type=return_tensors) if annotations is not None: # Convert to TensorType tensor_type = return_tensors if not isinstance(tensor_type, TensorType): tensor_type = TensorType(tensor_type) if not tensor_type == TensorType.PYTORCH: raise ValueError("Only PyTorch is supported for the moment.") else: if not is_torch_available(): raise ImportError("Unable to convert output to PyTorch tensors format, PyTorch is not installed.") encoded_inputs["labels"] = [ {k: torch.from_numpy(v) for k, v in target.items()} for target in annotations ] return encoded_inputs
def _max_by_axis(self, the_list): # type: (List[List[int]]) -> List[int] maxes = the_list[0] for sublist in the_list[1:]: for index, item in enumerate(sublist): maxes[index] = max(maxes[index], item) return maxes
[docs] def pad_and_create_pixel_mask( self, pixel_values_list: List["torch.Tensor"], return_tensors: Optional[Union[str, TensorType]] = None ): """ Pad images up to the largest image in a batch and create a corresponding :obj:`pixel_mask`. Args: pixel_values_list (:obj:`List[torch.Tensor]`): List of images (pixel values) to be padded. Each image should be a tensor of shape (C, H, W). return_tensors (:obj:`str` or :class:`~transformers.file_utils.TensorType`, `optional`): If set, will return tensors instead of NumPy arrays. If set to :obj:`'pt'`, return PyTorch :obj:`torch.Tensor` objects. Returns: :class:`~transformers.BatchFeature`: A :class:`~transformers.BatchFeature` with the following fields: - **pixel_values** -- Pixel values to be fed to a model. - **pixel_mask** -- Pixel mask to be fed to a model (when :obj:`pad_and_return_pixel_mask=True` or if `"pixel_mask"` is in :obj:`self.model_input_names`). """ max_size = self._max_by_axis([list(image.shape) for image in pixel_values_list]) c, h, w = max_size padded_images = [] pixel_mask = [] for image in pixel_values_list: # create padded image padded_image = np.zeros((c, h, w), dtype=np.float32) padded_image[: image.shape[0], : image.shape[1], : image.shape[2]] = np.copy(image) padded_images.append(padded_image) # create pixel mask mask = np.zeros((h, w), dtype=np.int64) mask[: image.shape[1], : image.shape[2]] = True pixel_mask.append(mask) # return as BatchFeature data = {"pixel_values": padded_images, "pixel_mask": pixel_mask} encoded_inputs = BatchFeature(data=data, tensor_type=return_tensors) return encoded_inputs
# POSTPROCESSING METHODS # inspired by https://github.com/facebookresearch/detr/blob/master/models/detr.py#L258
[docs] def post_process(self, outputs, target_sizes): """ Converts the output of :class:`~transformers.DetrForObjectDetection` into the format expected by the COCO api. Only supports PyTorch. Args: outputs (:class:`~transformers.DetrObjectDetectionOutput`): Raw outputs of the model. target_sizes (:obj:`torch.Tensor` of shape :obj:`(batch_size, 2)`, `optional`): Tensor containing the size (h, w) of each image of the batch. For evaluation, this must be the original image size (before any data augmentation). For visualization, this should be the image size after data augment, but before padding. Returns: :obj:`List[Dict]`: A list of dictionaries, each dictionary containing the scores, labels and boxes for an image in the batch as predicted by the model. """ out_logits, out_bbox = outputs.logits, outputs.pred_boxes assert len(out_logits) == len( target_sizes ), "Make sure that you pass in as many target sizes as the batch dimension of the logits" assert ( target_sizes.shape[1] == 2 ), "Each element of target_sizes must contain the size (h, w) of each image of the batch" prob = nn.functional.softmax(out_logits, -1) scores, labels = prob[..., :-1].max(-1) # convert to [x0, y0, x1, y1] format boxes = center_to_corners_format(out_bbox) # and from relative [0, 1] to absolute [0, height] coordinates img_h, img_w = target_sizes.unbind(1) scale_fct = torch.stack([img_w, img_h, img_w, img_h], dim=1) boxes = boxes * scale_fct[:, None, :] results = [{"scores": s, "labels": l, "boxes": b} for s, l, b in zip(scores, labels, boxes)] return results
# inspired by https://github.com/facebookresearch/detr/blob/master/models/segmentation.py#L218
[docs] def post_process_segmentation(self, results, outputs, orig_target_sizes, max_target_sizes, threshold=0.5): """ Converts the output of :class:`~transformers.DetrForSegmentation` into actual instance segmentation predictions. Only supports PyTorch. Args: results (:obj:`List[Dict]`): Results list obtained by :meth:`~transformers.DetrFeatureExtractor.post_process`, to which "masks" results will be added. outputs (:class:`~transformers.DetrSegmentationOutput`): Raw outputs of the model. orig_target_sizes (:obj:`torch.Tensor` of shape :obj:`(batch_size, 2)`): Tensor containing the size (h, w) of each image of the batch. For evaluation, this must be the original image size (before any data augmentation). max_target_sizes (:obj:`torch.Tensor` of shape :obj:`(batch_size, 2)`): Tensor containing the maximum size (h, w) of each image of the batch. For evaluation, this must be the original image size (before any data augmentation). threshold (:obj:`float`, `optional`, defaults to 0.5): Threshold to use when turning the predicted masks into binary values. Returns: :obj:`List[Dict]`: A list of dictionaries, each dictionary containing the scores, labels, boxes and masks for an image in the batch as predicted by the model. """ assert len(orig_target_sizes) == len( max_target_sizes ), "Make sure to pass in as many orig_target_sizes as max_target_sizes" max_h, max_w = max_target_sizes.max(0)[0].tolist() outputs_masks = outputs.pred_masks.squeeze(2) outputs_masks = nn.functional.interpolate( outputs_masks, size=(max_h, max_w), mode="bilinear", align_corners=False ) outputs_masks = (outputs_masks.sigmoid() > threshold).cpu() for i, (cur_mask, t, tt) in enumerate(zip(outputs_masks, max_target_sizes, orig_target_sizes)): img_h, img_w = t[0], t[1] results[i]["masks"] = cur_mask[:, :img_h, :img_w].unsqueeze(1) results[i]["masks"] = nn.functional.interpolate( results[i]["masks"].float(), size=tuple(tt.tolist()), mode="nearest" ).byte() return results
# inspired by https://github.com/facebookresearch/detr/blob/master/models/segmentation.py#L241
[docs] def post_process_panoptic(self, outputs, processed_sizes, target_sizes=None, is_thing_map=None, threshold=0.85): """ Converts the output of :class:`~transformers.DetrForSegmentation` into actual panoptic predictions. Only supports PyTorch. Parameters: outputs (:class:`~transformers.DetrSegmentationOutput`): Raw outputs of the model. processed_sizes (:obj:`torch.Tensor` of shape :obj:`(batch_size, 2)` or :obj:`List[Tuple]` of length :obj:`batch_size`): Torch Tensor (or list) containing the size (h, w) of each image of the batch, i.e. the size after data augmentation but before batching. target_sizes (:obj:`torch.Tensor` of shape :obj:`(batch_size, 2)` or :obj:`List[Tuple]` of length :obj:`batch_size`, `optional`): Torch Tensor (or list) corresponding to the requested final size (h, w) of each prediction. If left to None, it will default to the :obj:`processed_sizes`. is_thing_map (:obj:`torch.Tensor` of shape :obj:`(batch_size, 2)`, `optional`): Dictionary mapping class indices to either True or False, depending on whether or not they are a thing. If not set, defaults to the :obj:`is_thing_map` of COCO panoptic. threshold (:obj:`float`, `optional`, defaults to 0.85): Threshold to use to filter out queries. Returns: :obj:`List[Dict]`: A list of dictionaries, each dictionary containing a PNG string and segments_info values for an image in the batch as predicted by the model. """ if target_sizes is None: target_sizes = processed_sizes assert len(processed_sizes) == len( target_sizes ), "Make sure to pass in as many processed_sizes as target_sizes" if is_thing_map is None: # default to is_thing_map of COCO panoptic is_thing_map = {i: i <= 90 for i in range(201)} out_logits, raw_masks, raw_boxes = outputs.logits, outputs.pred_masks, outputs.pred_boxes assert ( len(out_logits) == len(raw_masks) == len(target_sizes) ), "Make sure that you pass in as many target sizes as the batch dimension of the logits and masks" preds = [] def to_tuple(tup): if isinstance(tup, tuple): return tup return tuple(tup.cpu().tolist()) for cur_logits, cur_masks, cur_boxes, size, target_size in zip( out_logits, raw_masks, raw_boxes, processed_sizes, target_sizes ): # we filter empty queries and detection below threshold scores, labels = cur_logits.softmax(-1).max(-1) keep = labels.ne(outputs.logits.shape[-1] - 1) & (scores > threshold) cur_scores, cur_classes = cur_logits.softmax(-1).max(-1) cur_scores = cur_scores[keep] cur_classes = cur_classes[keep] cur_masks = cur_masks[keep] cur_masks = nn.functional.interpolate(cur_masks[:, None], to_tuple(size), mode="bilinear").squeeze(1) cur_boxes = center_to_corners_format(cur_boxes[keep]) h, w = cur_masks.shape[-2:] assert len(cur_boxes) == len(cur_classes), "Not as many boxes as there are classes" # It may be that we have several predicted masks for the same stuff class. # In the following, we track the list of masks ids for each stuff class (they are merged later on) cur_masks = cur_masks.flatten(1) stuff_equiv_classes = defaultdict(lambda: []) for k, label in enumerate(cur_classes): if not is_thing_map[label.item()]: stuff_equiv_classes[label.item()].append(k) def get_ids_area(masks, scores, dedup=False): # This helper function creates the final panoptic segmentation image # It also returns the area of the masks that appears on the image m_id = masks.transpose(0, 1).softmax(-1) if m_id.shape[-1] == 0: # We didn't detect any mask :( m_id = torch.zeros((h, w), dtype=torch.long, device=m_id.device) else: m_id = m_id.argmax(-1).view(h, w) if dedup: # Merge the masks corresponding to the same stuff class for equiv in stuff_equiv_classes.values(): if len(equiv) > 1: for eq_id in equiv: m_id.masked_fill_(m_id.eq(eq_id), equiv[0]) final_h, final_w = to_tuple(target_size) seg_img = Image.fromarray(id_to_rgb(m_id.view(h, w).cpu().numpy())) seg_img = seg_img.resize(size=(final_w, final_h), resample=Image.NEAREST) np_seg_img = torch.ByteTensor(torch.ByteStorage.from_buffer(seg_img.tobytes())) np_seg_img = np_seg_img.view(final_h, final_w, 3) np_seg_img = np_seg_img.numpy() m_id = torch.from_numpy(rgb_to_id(np_seg_img)) area = [] for i in range(len(scores)): area.append(m_id.eq(i).sum().item()) return area, seg_img area, seg_img = get_ids_area(cur_masks, cur_scores, dedup=True) if cur_classes.numel() > 0: # We know filter empty masks as long as we find some while True: filtered_small = torch.as_tensor( [area[i] <= 4 for i, c in enumerate(cur_classes)], dtype=torch.bool, device=keep.device ) if filtered_small.any().item(): cur_scores = cur_scores[~filtered_small] cur_classes = cur_classes[~filtered_small] cur_masks = cur_masks[~filtered_small] area, seg_img = get_ids_area(cur_masks, cur_scores) else: break else: cur_classes = torch.ones(1, dtype=torch.long, device=cur_classes.device) segments_info = [] for i, a in enumerate(area): cat = cur_classes[i].item() segments_info.append({"id": i, "isthing": is_thing_map[cat], "category_id": cat, "area": a}) del cur_classes with io.BytesIO() as out: seg_img.save(out, format="PNG") predictions = {"png_string": out.getvalue(), "segments_info": segments_info} preds.append(predictions) return preds