Add HungarianMatcher (#2)

- added conditional_detr hungarian matcher (6da1a70d484731a1f9182e8d786f2aa5efed4f05)


Co-authored-by: Emanuele Vivoli <[email protected]>

conditional_detr_utils.py

@@ -0,0 +1,179 @@
+# coding=utf-8
+# Copyright 2022 Microsoft Research Asia and 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.
+""" PyTorch Conditional DETR model."""
+
+from transformers.utils import (
+    is_scipy_available,
+    is_vision_available,
+    logging
+)
+
+import torch
+from torch import Tensor, nn
+
+if is_scipy_available():
+    from scipy.optimize import linear_sum_assignment
+
+if is_vision_available():
+    from transformers.image_transforms import center_to_corners_format
+
+logger = logging.get_logger(__name__)
+
+# Copied from transformers.models.deformable_detr.modeling_deformable_detr.DeformableDetrHungarianMatcher with DeformableDetr->ConditionalDetr
+class ConditionalDetrHungarianMatcher(nn.Module):
+    """
+    This class computes an assignment between the targets and the predictions of the network.
+
+    For efficiency reasons, the targets don't include the no_object. Because of this, in general, there are more
+    predictions than targets. In this case, we do a 1-to-1 matching of the best predictions, while the others are
+    un-matched (and thus treated as non-objects).
+
+    Args:
+        class_cost:
+            The relative weight of the classification error in the matching cost.
+        bbox_cost:
+            The relative weight of the L1 error of the bounding box coordinates in the matching cost.
+        giou_cost:
+            The relative weight of the giou loss of the bounding box in the matching cost.
+    """
+
+    def __init__(self, class_cost: float = 1, bbox_cost: float = 1, giou_cost: float = 1):
+        super().__init__()
+
+        self.class_cost = class_cost
+        self.bbox_cost = bbox_cost
+        self.giou_cost = giou_cost
+        if class_cost == 0 and bbox_cost == 0 and giou_cost == 0:
+            raise ValueError("All costs of the Matcher can't be 0")
+
+    @torch.no_grad()
+    def forward(self, outputs, targets):
+        """
+        Args:
+            outputs (`dict`):
+                A dictionary that contains at least these entries:
+                * "logits": Tensor of dim [batch_size, num_queries, num_classes] with the classification logits
+                * "pred_boxes": Tensor of dim [batch_size, num_queries, 4] with the predicted box coordinates.
+            targets (`List[dict]`):
+                A list of targets (len(targets) = batch_size), where each target is a dict containing:
+                * "class_labels": Tensor of dim [num_target_boxes] (where num_target_boxes is the number of
+                  ground-truth
+                 objects in the target) containing the class labels
+                * "boxes": Tensor of dim [num_target_boxes, 4] containing the target box coordinates.
+
+        Returns:
+            `List[Tuple]`: A list of size `batch_size`, containing tuples of (index_i, index_j) where:
+            - index_i is the indices of the selected predictions (in order)
+            - index_j is the indices of the corresponding selected targets (in order)
+            For each batch element, it holds: len(index_i) = len(index_j) = min(num_queries, num_target_boxes)
+        """
+        batch_size, num_queries = outputs["logits"].shape[:2]
+
+        # We flatten to compute the cost matrices in a batch
+        out_prob = outputs["logits"].flatten(0, 1).sigmoid()  # [batch_size * num_queries, num_classes]
+        out_bbox = outputs["pred_boxes"].flatten(0, 1)  # [batch_size * num_queries, 4]
+
+        # Also concat the target labels and boxes
+        target_ids = torch.cat([v["class_labels"] for v in targets])
+        target_bbox = torch.cat([v["boxes"] for v in targets])
+
+        # Compute the classification cost.
+        alpha = 0.25
+        gamma = 2.0
+        neg_cost_class = (1 - alpha) * (out_prob**gamma) * (-(1 - out_prob + 1e-8).log())
+        pos_cost_class = alpha * ((1 - out_prob) ** gamma) * (-(out_prob + 1e-8).log())
+        class_cost = pos_cost_class[:, target_ids] - neg_cost_class[:, target_ids]
+
+        # Compute the L1 cost between boxes
+        bbox_cost = torch.cdist(out_bbox, target_bbox, p=1)
+
+        # Compute the giou cost between boxes
+        giou_cost = -generalized_box_iou(center_to_corners_format(out_bbox), center_to_corners_format(target_bbox))
+
+        # Final cost matrix
+        cost_matrix = self.bbox_cost * bbox_cost + self.class_cost * class_cost + self.giou_cost * giou_cost
+        cost_matrix = cost_matrix.view(batch_size, num_queries, -1).cpu()
+
+        sizes = [len(v["boxes"]) for v in targets]
+        indices = [linear_sum_assignment(c[i]) for i, c in enumerate(cost_matrix.split(sizes, -1))]
+        return [(torch.as_tensor(i, dtype=torch.int64), torch.as_tensor(j, dtype=torch.int64)) for i, j in indices]
+
+
+# Copied from transformers.models.detr.modeling_detr._upcast
+def _upcast(t: Tensor) -> Tensor:
+    # Protects from numerical overflows in multiplications by upcasting to the equivalent higher type
+    if t.is_floating_point():
+        return t if t.dtype in (torch.float32, torch.float64) else t.float()
+    else:
+        return t if t.dtype in (torch.int32, torch.int64) else t.int()
+
+
+# Copied from transformers.models.detr.modeling_detr.box_area
+def box_area(boxes: Tensor) -> Tensor:
+    """
+    Computes the area of a set of bounding boxes, which are specified by its (x1, y1, x2, y2) coordinates.
+
+    Args:
+        boxes (`torch.FloatTensor` of shape `(number_of_boxes, 4)`):
+            Boxes for which the area will be computed. They are expected to be in (x1, y1, x2, y2) format with `0 <= x1
+            < x2` and `0 <= y1 < y2`.
+
+    Returns:
+        `torch.FloatTensor`: a tensor containing the area for each box.
+    """
+    boxes = _upcast(boxes)
+    return (boxes[:, 2] - boxes[:, 0]) * (boxes[:, 3] - boxes[:, 1])
+
+
+# Copied from transformers.models.detr.modeling_detr.box_iou
+def box_iou(boxes1, boxes2):
+    area1 = box_area(boxes1)
+    area2 = box_area(boxes2)
+
+    left_top = torch.max(boxes1[:, None, :2], boxes2[:, :2])  # [N,M,2]
+    right_bottom = torch.min(boxes1[:, None, 2:], boxes2[:, 2:])  # [N,M,2]
+
+    width_height = (right_bottom - left_top).clamp(min=0)  # [N,M,2]
+    inter = width_height[:, :, 0] * width_height[:, :, 1]  # [N,M]
+
+    union = area1[:, None] + area2 - inter
+
+    iou = inter / union
+    return iou, union
+
+
+# Copied from transformers.models.detr.modeling_detr.generalized_box_iou
+def generalized_box_iou(boxes1, boxes2):
+    """
+    Generalized IoU from https://giou.stanford.edu/. The boxes should be in [x0, y0, x1, y1] (corner) format.
+
+    Returns:
+        `torch.FloatTensor`: a [N, M] pairwise matrix, where N = len(boxes1) and M = len(boxes2)
+    """
+    # degenerate boxes gives inf / nan results
+    # so do an early check
+    if not (boxes1[:, 2:] >= boxes1[:, :2]).all():
+        raise ValueError(f"boxes1 must be in [x0, y0, x1, y1] (corner) format, but got {boxes1}")
+    if not (boxes2[:, 2:] >= boxes2[:, :2]).all():
+        raise ValueError(f"boxes2 must be in [x0, y0, x1, y1] (corner) format, but got {boxes2}")
+    iou, union = box_iou(boxes1, boxes2)
+
+    top_left = torch.min(boxes1[:, None, :2], boxes2[:, :2])
+    bottom_right = torch.max(boxes1[:, None, 2:], boxes2[:, 2:])
+
+    width_height = (bottom_right - top_left).clamp(min=0)  # [N,M,2]
+    area = width_height[:, :, 0] * width_height[:, :, 1]
+
+    return iou - (area - union) / area

modelling_magi.py

@@ -2,15 +2,15 @@ from transformers import PreTrainedModel, VisionEncoderDecoderModel, ViTMAEModel
 from transformers.models.conditional_detr.modeling_conditional_detr import (
     ConditionalDetrMLPPredictionHead, 
     ConditionalDetrModelOutput,
-    ConditionalDetrHungarianMatcher,
     inverse_sigmoid,
 )
+from .conditional_detr_utils import ConditionalDetrHungarianMatcher
 from .configuration_magi import MagiConfig
 from .processing_magi import MagiProcessor
 from torch import nn
 from typing import Optional, List
 import torch
-from einops import rearrange, repeat, einsum
+from einops import rearrange, repeat
 from .utils import move_to_device, visualise_single_image_prediction, sort_panels, sort_text_boxes_in_reading_order
 
 class MagiModel(PreTrainedModel):
@@ -498,4 +498,5 @@ class MagiModel(PreTrainedModel):
             if apply_sigmoid:
                 text_character_affinities = text_character_affinities.sigmoid()
             affinity_matrices.append(text_character_affinities)
-        return affinity_matrices
+        return affinity_matrices
+