fix

research/object_detection/box_coders/detr_box_coder.py

+# Copyright 2017 The TensorFlow Authors. 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.
+# ==============================================================================
+
+"""Faster RCNN box coder.
+
+Faster RCNN box coder follows the coding schema described below:
+  ty = (y - ya) / ha
+  tx = (x - xa) / wa
+  th = log(h / ha)
+  tw = log(w / wa)
+  where x, y, w, h denote the box's center coordinates, width and height
+  respectively. Similarly, xa, ya, wa, ha denote the anchor's center
+  coordinates, width and height. tx, ty, tw and th denote the anchor-encoded
+  center, width and height respectively.
+
+  See http://arxiv.org/abs/1506.01497 for details.
+"""
+
+import tensorflow.compat.v1 as tf
+
+from object_detection.core import box_coder
+from object_detection.core import box_list
+
+EPSILON = 1e-8
+
+
+class DETRBoxCoder(box_coder.BoxCoder):
+  """Faster RCNN box coder."""
+
+  def __init__(self, scale_factors=None):
+    """Constructor for FasterRcnnBoxCoder.
+
+    Args:
+      scale_factors: List of 4 positive scalars to scale ty, tx, th and tw.
+        If set to None, does not perform scaling. For Faster RCNN,
+        the open-source implementation recommends using [10.0, 10.0, 5.0, 5.0].
+    """
+    if None:
+      assert len(scale_factors) == 4
+      for scalar in scale_factors:
+        assert scalar > 0
+    self._scale_factors = scale_factors
+
+  @property
+  def code_size(self):
+    return 4
+
+  def _encode(self, boxes, anchors):
+    """Encode a box collection with respect to anchor collection.
+
+    Args:
+      boxes: BoxList holding N boxes to be encoded.
+      anchors: BoxList of anchors.
+
+    Returns:
+      a tensor representing N anchor-encoded boxes of the format
+      [ty, tx, th, tw].
+    """
+    # Convert anchors to the center coordinate representation.
+    ycenter, xcenter, h, w = boxes.get_center_coordinates_and_sizes()
+    # Avoid NaN in division and log below.
+    h += EPSILON
+    w += EPSILON
+
+    tx = xcenter
+    ty = ycenter
+    tw = w #tf.log(w)
+    th = h #tf.log(h)
+    
+    return tf.transpose(tf.stack([ty, tx, th, tw]))
+
+  def _decode(self, rel_codes, anchors):
+    """Decode relative codes to boxes.
+
+    Args:
+      rel_codes: a tensor representing N anchor-encoded boxes.
+      anchors: BoxList of anchors.
+
+    Returns:
+      boxes: BoxList holding N bounding boxes.
+    """
+    ty, tx, th, tw = tf.unstack(tf.transpose(rel_codes))
+
+    w = tw
+    h = th 
+    ycenter = ty
+    xcenter = tx
+    ymin = ycenter - h / 2.
+    xmin = xcenter - w / 2.
+    ymax = ycenter + h / 2.
+    xmax = xcenter + w / 2.
+    return box_list.BoxList(tf.transpose(tf.stack([ymin, xmin, ymax, xmax])))
+

research/object_detection/core/target_assigner.py

@@ -446,7 +446,7 @@ def create_target_assigner(reference, stage=None,
   elif reference == 'DETR':
     similarity_calc = sim_calc.DETRSimilarity()
     matcher = hungarian_matcher.HungarianBipartiteMatcher()
-    box_coder_instance = None
+    box_coder_instance = detr_box_coder.DETRBoxCoder()
 
   else:
     raise ValueError('No valid combination of reference and stage.')
@@ -481,6 +481,7 @@ def batch_assign(target_assigner,
       function (which have shape [num_gt_boxes, d_1, d_2, ..., d_k]).
     gt_weights_batch: A list of 1-D tf.float32 tensors of shape
       [num_boxes] containing weights for groundtruth boxes.
+    class_predictions: A 
 
   Returns:
     batch_cls_targets: a tensor with shape [batch_size, num_anchors,
@@ -521,7 +522,10 @@ def batch_assign(target_assigner,
   match_list = []
   if gt_weights_batch is None:
     gt_weights_batch = [None] * len(gt_class_targets_batch)
-  class_predictions = tf.unstack(class_predictions)
+  if class_predictions:
+    class_predictions = tf.unstack(class_predictions)
+  else:
+    class_predictions = [None] * len(gt_class_targets_batch)
   for anchors, gt_boxes, gt_class_targets, gt_weights, class_preds in zip(
       anchors_batch, gt_box_batch, gt_class_targets_batch, gt_weights_batch,
       class_predictions):

research/object_detection/core/target_assigner_test.py

@@ -19,6 +19,7 @@ import tensorflow.compat.v1 as tf
 
 from object_detection.box_coders import keypoint_box_coder
 from object_detection.box_coders import mean_stddev_box_coder
+from object_detection.box_coders import detr_box_coder
 from object_detection.core import box_list
 from object_detection.core import region_similarity_calculator
 from object_detection.core import standard_fields as fields
@@ -1927,7 +1928,7 @@ class CenterNetMaskTargetAssignerTest(test_case.TestCase):
                  groundtruth_labels, predicted_labels):
       similarity_calc = region_similarity_calculator.DETRSimilarity()
       matcher = hungarian_matcher.HungarianBipartiteMatcher()
-      box_coder = box
+      box_coder = detr_box_coder.DETRBoxCoder()
       target_assigner = targetassigner.TargetAssigner(
           similarity_calc, matcher, box_coder)
       anchors_boxlist = box_list.BoxList(anchor_means)