Exemplo n.º 1
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 def test_raise_value_error_on_empty_anchor_genertor(self):
     anchor_generator_text_proto = """
 """
     anchor_generator_proto = anchor_generator_pb2.AnchorGenerator()
     text_format.Merge(anchor_generator_text_proto, anchor_generator_proto)
     with self.assertRaises(ValueError):
         anchor_generator_builder.build(anchor_generator_proto)
Exemplo n.º 2
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    def test_build_ssd_anchor_generator_with_defaults(self):
        anchor_generator_text_proto = """
      ssd_anchor_generator {
        aspect_ratios: [1.0]
      }
    """
        anchor_generator_proto = anchor_generator_pb2.AnchorGenerator()
        text_format.Merge(anchor_generator_text_proto, anchor_generator_proto)
        anchor_generator_object = anchor_generator_builder.build(
            anchor_generator_proto)
        self.assertTrue(
            isinstance(
                anchor_generator_object,
                multiple_grid_anchor_generator.MultipleGridAnchorGenerator))
        for actual_scales, expected_scales in zip(
                list(anchor_generator_object._scales), [(0.1, 0.2, 0.2),
                                                        (0.35, 0.418),
                                                        (0.499, 0.570),
                                                        (0.649, 0.721),
                                                        (0.799, 0.871),
                                                        (0.949, 0.974)]):
            self.assert_almost_list_equal(expected_scales,
                                          actual_scales,
                                          delta=1e-2)
        # noinspection PyTypeChecker
        for actual_aspect_ratio, expected_aspect_ratio in zip(
                list(anchor_generator_object._aspect_ratios),
            [(1.0, 2.0, 0.5)] + 5 * [(1.0, 1.0)]):
            self.assert_almost_list_equal(expected_aspect_ratio,
                                          actual_aspect_ratio)

        with self.test_session() as sess:
            base_anchor_size = sess.run(
                anchor_generator_object._base_anchor_size)
        self.assertAllClose(base_anchor_size, [1.0, 1.0])
Exemplo n.º 3
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 def test_build_grid_anchor_generator_with_non_default_parameters(self):
     anchor_generator_text_proto = """
   grid_anchor_generator {
     height: 128
     width: 512
     height_stride: 10
     width_stride: 20
     height_offset: 30
     width_offset: 40
     scales: [0.4, 2.2]
     aspect_ratios: [0.3, 4.5]
   }
  """
     anchor_generator_proto = anchor_generator_pb2.AnchorGenerator()
     text_format.Merge(anchor_generator_text_proto, anchor_generator_proto)
     anchor_generator_object = anchor_generator_builder.build(
         anchor_generator_proto)
     self.assertTrue(
         isinstance(anchor_generator_object,
                    grid_anchor_generator.GridAnchorGenerator))
     self.assert_almost_list_equal(anchor_generator_object._scales,
                                   [0.4, 2.2])
     self.assert_almost_list_equal(anchor_generator_object._aspect_ratios,
                                   [0.3, 4.5])
     with self.test_session() as sess:
         base_anchor_size, anchor_offset, anchor_stride = sess.run([
             anchor_generator_object._base_anchor_size,
             anchor_generator_object._anchor_offset,
             anchor_generator_object._anchor_stride
         ])
     self.assertAllEqual(anchor_offset, [30, 40])
     self.assertAllEqual(anchor_stride, [10, 20])
     self.assertAllEqual(base_anchor_size, [128, 512])
Exemplo n.º 4
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 def test_build_multiscale_anchor_generator_custom_aspect_ratios(self):
     anchor_generator_text_proto = """
   multiscale_anchor_generator {
     aspect_ratios: [1.0]
   }
 """
     anchor_generator_proto = anchor_generator_pb2.AnchorGenerator()
     text_format.Merge(anchor_generator_text_proto, anchor_generator_proto)
     anchor_generator_object = anchor_generator_builder.build(
         anchor_generator_proto)
     self.assertTrue(
         isinstance(
             anchor_generator_object, multiscale_grid_anchor_generator.
             MultiscaleGridAnchorGenerator))
     for level, anchor_grid_info in zip(
             range(3, 8), anchor_generator_object._anchor_grid_info):
         self.assertEqual(set(anchor_grid_info.keys()), {'level', 'info'})
         self.assertTrue(level, anchor_grid_info['level'])
         self.assertEqual(len(anchor_grid_info['info']), 4)
         self.assertAllClose(anchor_grid_info['info'][0], [2**0, 2**0.5])
         self.assertTrue(anchor_grid_info['info'][1], 1.0)
         self.assertAllClose(anchor_grid_info['info'][2],
                             [4.0 * 2**level, 4.0 * 2**level])
         self.assertAllClose(anchor_grid_info['info'][3],
                             [2**level, 2**level])
         self.assertTrue(anchor_generator_object._normalize_coordinates)
Exemplo n.º 5
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    def test_build_ssd_anchor_generator_with_non_default_parameters(self):
        anchor_generator_text_proto = """
      ssd_anchor_generator {
        num_layers: 2
        min_scale: 0.3
        max_scale: 0.8
        aspect_ratios: [2.0]
        height_stride: 16
        height_stride: 32
        width_stride: 20
        width_stride: 30
        height_offset: 8
        height_offset: 16
        width_offset: 0
        width_offset: 10
      }
    """
        anchor_generator_proto = anchor_generator_pb2.AnchorGenerator()
        text_format.Merge(anchor_generator_text_proto, anchor_generator_proto)
        anchor_generator_object = anchor_generator_builder.build(
            anchor_generator_proto)
        self.assertTrue(
            isinstance(
                anchor_generator_object,
                multiple_grid_anchor_generator.MultipleGridAnchorGenerator))

        for actual_scales, expected_scales in zip(
                list(anchor_generator_object._scales), [(0.1, 0.3, 0.3),
                                                        (0.8, 0.894)]):
            self.assert_almost_list_equal(expected_scales,
                                          actual_scales,
                                          delta=1e-2)

        for actual_aspect_ratio, expected_aspect_ratio in zip(
                list(anchor_generator_object._aspect_ratios), [(1.0, 2.0, 0.5),
                                                               (2.0, 1.0)]):
            self.assert_almost_list_equal(expected_aspect_ratio,
                                          actual_aspect_ratio)

        for actual_strides, expected_strides in zip(
                list(anchor_generator_object._anchor_strides), [(16, 20),
                                                                (32, 30)]):
            self.assert_almost_list_equal(expected_strides, actual_strides)

        for actual_offsets, expected_offsets in zip(
                list(anchor_generator_object._anchor_offsets), [(8, 0),
                                                                (16, 10)]):
            self.assert_almost_list_equal(expected_offsets, actual_offsets)

        with self.test_session() as sess:
            base_anchor_size = sess.run(
                anchor_generator_object._base_anchor_size)
        self.assertAllClose(base_anchor_size, [1.0, 1.0])
Exemplo n.º 6
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 def test_build_multiscale_anchor_generator_with_anchors_in_pixel_coordinates(
         self):
     anchor_generator_text_proto = """
   multiscale_anchor_generator {
     aspect_ratios: [1.0]
     normalize_coordinates: false
   }
 """
     anchor_generator_proto = anchor_generator_pb2.AnchorGenerator()
     text_format.Merge(anchor_generator_text_proto, anchor_generator_proto)
     anchor_generator_object = anchor_generator_builder.build(
         anchor_generator_proto)
     self.assertTrue(
         isinstance(
             anchor_generator_object, multiscale_grid_anchor_generator.
             MultiscaleGridAnchorGenerator))
     self.assertFalse(anchor_generator_object._normalize_coordinates)
Exemplo n.º 7
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 def test_build_ssd_anchor_generator_with_custom_interpolated_scale(self):
     anchor_generator_text_proto = """
   ssd_anchor_generator {
     aspect_ratios: [0.5]
     interpolated_scale_aspect_ratio: 0.5
     reduce_boxes_in_lowest_layer: false
   }
 """
     anchor_generator_proto = anchor_generator_pb2.AnchorGenerator()
     text_format.Merge(anchor_generator_text_proto, anchor_generator_proto)
     anchor_generator_object = anchor_generator_builder.build(
         anchor_generator_proto)
     self.assertTrue(
         isinstance(
             anchor_generator_object,
             multiple_grid_anchor_generator.MultipleGridAnchorGenerator))
     for actual_aspect_ratio, expected_aspect_ratio in zip(
             list(anchor_generator_object._aspect_ratios),
             6 * [(0.5, 0.5)]):
         self.assert_almost_list_equal(expected_aspect_ratio,
                                       actual_aspect_ratio)
Exemplo n.º 8
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 def test_build_grid_anchor_generator_with_defaults(self):
     anchor_generator_text_proto = """
   grid_anchor_generator {
   }
  """
     anchor_generator_proto = anchor_generator_pb2.AnchorGenerator()
     text_format.Merge(anchor_generator_text_proto, anchor_generator_proto)
     anchor_generator_object = anchor_generator_builder.build(
         anchor_generator_proto)
     self.assertTrue(
         isinstance(anchor_generator_object,
                    grid_anchor_generator.GridAnchorGenerator))
     self.assertListEqual(anchor_generator_object._scales, [])
     self.assertListEqual(anchor_generator_object._aspect_ratios, [])
     with self.test_session() as sess:
         base_anchor_size, anchor_offset, anchor_stride = sess.run([
             anchor_generator_object._base_anchor_size,
             anchor_generator_object._anchor_offset,
             anchor_generator_object._anchor_stride
         ])
     self.assertAllEqual(anchor_offset, [0, 0])
     self.assertAllEqual(anchor_stride, [16, 16])
     self.assertAllEqual(base_anchor_size, [256, 256])
Exemplo n.º 9
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    def test_build_ssd_anchor_generator_without_reduced_boxes(self):
        anchor_generator_text_proto = """
      ssd_anchor_generator {
        aspect_ratios: [1.0]
        reduce_boxes_in_lowest_layer: false
      }
    """
        anchor_generator_proto = anchor_generator_pb2.AnchorGenerator()
        text_format.Merge(anchor_generator_text_proto, anchor_generator_proto)
        anchor_generator_object = anchor_generator_builder.build(
            anchor_generator_proto)
        self.assertTrue(
            isinstance(
                anchor_generator_object,
                multiple_grid_anchor_generator.MultipleGridAnchorGenerator))

        for actual_scales, expected_scales in zip(
                list(anchor_generator_object._scales), [(0.2, 0.264),
                                                        (0.35, 0.418),
                                                        (0.499, 0.570),
                                                        (0.649, 0.721),
                                                        (0.799, 0.871),
                                                        (0.949, 0.974)]):
            self.assert_almost_list_equal(expected_scales,
                                          actual_scales,
                                          delta=1e-2)

        for actual_aspect_ratio, expected_aspect_ratio in zip(
                list(anchor_generator_object._aspect_ratios),
                6 * [(1.0, 1.0)]):
            self.assert_almost_list_equal(expected_aspect_ratio,
                                          actual_aspect_ratio)

        with self.test_session() as sess:
            base_anchor_size = sess.run(
                anchor_generator_object._base_anchor_size)
        self.assertAllClose(base_anchor_size, [1.0, 1.0])
Exemplo n.º 10
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 def test_build_ssd_anchor_generator_with_custom_scales(self):
     anchor_generator_text_proto = """
   ssd_anchor_generator {
     aspect_ratios: [1.0]
     scales: [0.1, 0.15, 0.2, 0.4, 0.6, 0.8]
     reduce_boxes_in_lowest_layer: false
   }
 """
     anchor_generator_proto = anchor_generator_pb2.AnchorGenerator()
     text_format.Merge(anchor_generator_text_proto, anchor_generator_proto)
     anchor_generator_object = anchor_generator_builder.build(
         anchor_generator_proto)
     self.assertTrue(
         isinstance(
             anchor_generator_object,
             multiple_grid_anchor_generator.MultipleGridAnchorGenerator))
     for actual_scales, expected_scales in zip(
             list(anchor_generator_object._scales),
         [(0.1, math.sqrt(0.1 * 0.15)), (0.15, math.sqrt(0.15 * 0.2)),
          (0.2, math.sqrt(0.2 * 0.4)), (0.4, math.sqrt(0.4 * 0.6)),
          (0.6, math.sqrt(0.6 * 0.8)), (0.8, math.sqrt(0.8 * 1.0))]):
         self.assert_almost_list_equal(expected_scales,
                                       actual_scales,
                                       delta=1e-2)
Exemplo n.º 11
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def _build_faster_rcnn_model(frcnn_config, is_training, add_summaries):
    """Builds a Faster R-CNN or R-FCN detection model based on the model config.

  Builds R-FCN model if the second_stage_box_predictor in the config is of type
  `rfcn_box_predictor` else builds a Faster R-CNN model.

  Args:
    frcnn_config: A faster_rcnn.proto object containing the config for the
      desired FasterRCNNMetaArch or RFCNMetaArch.
    is_training: True if this model is being built for training purposes.
    add_summaries: Whether to add tf summaries in the model.

  Returns:
    FasterRCNNMetaArch based on the config.

  Raises:
    ValueError: If frcnn_config.type is not recognized (i.e. not registered in
      model_class_map).
  """
    num_classes = frcnn_config.num_classes
    image_resizer_fn = image_resizer_builder.build(frcnn_config.image_resizer)

    feature_extractor = _build_faster_rcnn_feature_extractor(
        frcnn_config.feature_extractor, is_training,
        frcnn_config.inplace_batchnorm_update)

    number_of_stages = frcnn_config.number_of_stages
    first_stage_anchor_generator = anchor_generator_builder.build(
        frcnn_config.first_stage_anchor_generator)

    first_stage_atrous_rate = frcnn_config.first_stage_atrous_rate
    first_stage_box_predictor_arg_scope_fn = hyperparams_builder.build(
        frcnn_config.first_stage_box_predictor_conv_hyperparams, is_training)
    first_stage_box_predictor_kernel_size = (
        frcnn_config.first_stage_box_predictor_kernel_size)
    first_stage_box_predictor_depth = frcnn_config.first_stage_box_predictor_depth
    first_stage_minibatch_size = frcnn_config.first_stage_minibatch_size
    first_stage_positive_balance_fraction = (
        frcnn_config.first_stage_positive_balance_fraction)
    first_stage_nms_score_threshold = frcnn_config.first_stage_nms_score_threshold
    first_stage_nms_iou_threshold = frcnn_config.first_stage_nms_iou_threshold
    first_stage_max_proposals = frcnn_config.first_stage_max_proposals
    first_stage_loc_loss_weight = (
        frcnn_config.first_stage_localization_loss_weight)
    first_stage_obj_loss_weight = frcnn_config.first_stage_objectness_loss_weight

    initial_crop_size = frcnn_config.initial_crop_size
    maxpool_kernel_size = frcnn_config.maxpool_kernel_size
    maxpool_stride = frcnn_config.maxpool_stride

    second_stage_box_predictor = box_predictor_builder.build(
        hyperparams_builder.build,
        frcnn_config.second_stage_box_predictor,
        is_training=is_training,
        num_classes=num_classes)
    second_stage_batch_size = frcnn_config.second_stage_batch_size
    second_stage_balance_fraction = frcnn_config.second_stage_balance_fraction
    (second_stage_non_max_suppression_fn,
     second_stage_score_conversion_fn) = post_processing_builder.build(
         frcnn_config.second_stage_post_processing)
    second_stage_localization_loss_weight = (
        frcnn_config.second_stage_localization_loss_weight)
    second_stage_classification_loss = (
        losses_builder.build_faster_rcnn_classification_loss(
            frcnn_config.second_stage_classification_loss))
    second_stage_classification_loss_weight = (
        frcnn_config.second_stage_classification_loss_weight)
    second_stage_mask_prediction_loss_weight = (
        frcnn_config.second_stage_mask_prediction_loss_weight)

    hard_example_miner = None
    if frcnn_config.HasField('hard_example_miner'):
        hard_example_miner = losses_builder.build_hard_example_miner(
            frcnn_config.hard_example_miner,
            second_stage_classification_loss_weight,
            second_stage_localization_loss_weight)

    common_kwargs = {
        'is_training': is_training,
        'num_classes': num_classes,
        'image_resizer_fn': image_resizer_fn,
        'feature_extractor': feature_extractor,
        'number_of_stages': number_of_stages,
        'first_stage_anchor_generator': first_stage_anchor_generator,
        'first_stage_atrous_rate': first_stage_atrous_rate,
        'first_stage_box_predictor_arg_scope_fn':
        first_stage_box_predictor_arg_scope_fn,
        'first_stage_box_predictor_kernel_size':
        first_stage_box_predictor_kernel_size,
        'first_stage_box_predictor_depth': first_stage_box_predictor_depth,
        'first_stage_minibatch_size': first_stage_minibatch_size,
        'first_stage_positive_balance_fraction':
        first_stage_positive_balance_fraction,
        'first_stage_nms_score_threshold': first_stage_nms_score_threshold,
        'first_stage_nms_iou_threshold': first_stage_nms_iou_threshold,
        'first_stage_max_proposals': first_stage_max_proposals,
        'first_stage_localization_loss_weight': first_stage_loc_loss_weight,
        'first_stage_objectness_loss_weight': first_stage_obj_loss_weight,
        'second_stage_batch_size': second_stage_batch_size,
        'second_stage_balance_fraction': second_stage_balance_fraction,
        'second_stage_non_max_suppression_fn':
        second_stage_non_max_suppression_fn,
        'second_stage_score_conversion_fn': second_stage_score_conversion_fn,
        'second_stage_localization_loss_weight':
        second_stage_localization_loss_weight,
        'second_stage_classification_loss': second_stage_classification_loss,
        'second_stage_classification_loss_weight':
        second_stage_classification_loss_weight,
        'hard_example_miner': hard_example_miner,
        'add_summaries': add_summaries
    }

    if isinstance(second_stage_box_predictor, box_predictor.RfcnBoxPredictor):
        return rfcn_meta_arch.RFCNMetaArch(
            second_stage_rfcn_box_predictor=second_stage_box_predictor,
            **common_kwargs)
    else:
        return faster_rcnn_meta_arch.FasterRCNNMetaArch(
            initial_crop_size=initial_crop_size,
            maxpool_kernel_size=maxpool_kernel_size,
            maxpool_stride=maxpool_stride,
            second_stage_mask_rcnn_box_predictor=second_stage_box_predictor,
            second_stage_mask_prediction_loss_weight=(
                second_stage_mask_prediction_loss_weight),
            **common_kwargs)
Exemplo n.º 12
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def _build_ssd_model(ssd_config,
                     is_training,
                     add_summaries,
                     add_background_class=True):
    """Builds an SSD detection model based on the model config.

  Args:
    ssd_config: A ssd.proto object containing the config for the desired
      SSDMetaArch.
    is_training: True if this model is being built for training purposes.
    add_summaries: Whether to add tf summaries in the model.
    add_background_class: Whether to add an implicit background class to one-hot
      encodings of groundtruth labels. Set to false if using groundtruth labels
      with an explicit background class or using multiclass scores instead of
      truth in the case of distillation.
  Returns:
    SSDMetaArch based on the config.

  Raises:
    ValueError: If ssd_config.type is not recognized (i.e. not registered in
      model_class_map).
  """
    num_classes = ssd_config.num_classes

    # Feature extractor
    feature_extractor = _build_ssd_feature_extractor(
        feature_extractor_config=ssd_config.feature_extractor,
        is_training=is_training)

    box_coder = box_coder_builder.build(ssd_config.box_coder)
    matcher = matcher_builder.build(ssd_config.matcher)
    region_similarity_calculator = sim_calc.build(
        ssd_config.similarity_calculator)
    encode_background_as_zeros = ssd_config.encode_background_as_zeros
    negative_class_weight = ssd_config.negative_class_weight
    ssd_box_predictor = box_predictor_builder.build(hyperparams_builder.build,
                                                    ssd_config.box_predictor,
                                                    is_training, num_classes)
    anchor_generator = anchor_generator_builder.build(
        ssd_config.anchor_generator)
    image_resizer_fn = image_resizer_builder.build(ssd_config.image_resizer)
    non_max_suppression_fn, score_conversion_fn = post_processing_builder.build(
        ssd_config.post_processing)
    (classification_loss, localization_loss, classification_weight,
     localization_weight, hard_example_miner,
     random_example_sampler) = losses_builder.build(ssd_config.loss)
    normalize_loss_by_num_matches = ssd_config.normalize_loss_by_num_matches
    normalize_loc_loss_by_codesize = ssd_config.normalize_loc_loss_by_codesize

    return ssd_meta_arch.SSDMetaArch(
        is_training,
        anchor_generator,
        ssd_box_predictor,
        box_coder,
        feature_extractor,
        matcher,
        region_similarity_calculator,
        encode_background_as_zeros,
        negative_class_weight,
        image_resizer_fn,
        non_max_suppression_fn,
        score_conversion_fn,
        classification_loss,
        localization_loss,
        classification_weight,
        localization_weight,
        normalize_loss_by_num_matches,
        hard_example_miner,
        add_summaries=add_summaries,
        normalize_loc_loss_by_codesize=normalize_loc_loss_by_codesize,
        freeze_batchnorm=ssd_config.freeze_batchnorm,
        inplace_batchnorm_update=ssd_config.inplace_batchnorm_update,
        add_background_class=add_background_class,
        random_example_sampler=random_example_sampler)
Exemplo n.º 13
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def _build_faster_rcnn_model(frcnn_config, is_training, add_summaries):
    """Builds a Faster R-CNN or R-FCN detection model based on the model config.

  Builds R-FCN model if the second_stage_box_predictor in the config is of type
  `rfcn_box_predictor` else builds a Faster R-CNN model.

  Args:
    frcnn_config: A faster_rcnn.proto object containing the config for the
      desired FasterRCNNMetaArch or RFCNMetaArch.
    is_training: True if this model is being built for training purposes.
    add_summaries: Whether to add tf summaries in the model.

  Returns:
    FasterRCNNMetaArch based on the config.

  Raises:
    ValueError: If frcnn_config.type is not recognized (i.e. not registered in
      model_class_map).
  """
    num_classes = frcnn_config.num_classes
    image_resizer_fn = image_resizer_builder.build(frcnn_config.image_resizer)

    feature_extractor = _build_faster_rcnn_feature_extractor(
        frcnn_config.feature_extractor, is_training,
        frcnn_config.inplace_batchnorm_update)

    number_of_stages = frcnn_config.number_of_stages
    first_stage_anchor_generator = anchor_generator_builder.build(
        frcnn_config.first_stage_anchor_generator)

    first_stage_target_assigner = target_assigner.create_target_assigner(
        'FasterRCNN',
        'proposal',
        use_matmul_gather=frcnn_config.use_matmul_gather_in_matcher)
    first_stage_atrous_rate = frcnn_config.first_stage_atrous_rate
    first_stage_box_predictor_arg_scope_fn = hyperparams_builder.build(
        frcnn_config.first_stage_box_predictor_conv_hyperparams, is_training)
    first_stage_box_predictor_kernel_size = (
        frcnn_config.first_stage_box_predictor_kernel_size)
    first_stage_box_predictor_depth = frcnn_config.first_stage_box_predictor_depth
    first_stage_minibatch_size = frcnn_config.first_stage_minibatch_size
    # TODO(bhattad): When eval is supported using static shapes, add separate
    # use_static_shapes_for_trainig and use_static_shapes_for_evaluation.
    use_static_shapes = frcnn_config.use_static_shapes and is_training
    first_stage_sampler = sampler.BalancedPositiveNegativeSampler(
        positive_fraction=frcnn_config.first_stage_positive_balance_fraction,
        is_static=frcnn_config.use_static_balanced_label_sampler and is_training)
    first_stage_max_proposals = frcnn_config.first_stage_max_proposals
    if (frcnn_config.first_stage_nms_iou_threshold < 0 or
            frcnn_config.first_stage_nms_iou_threshold > 1.0):
        raise ValueError('iou_threshold not in [0, 1.0].')
    if (is_training and frcnn_config.second_stage_batch_size >
            first_stage_max_proposals):
        raise ValueError('second_stage_batch_size should be no greater than '
                         'first_stage_max_proposals.')
    first_stage_non_max_suppression_fn = functools.partial(
        post_processing.batch_multiclass_non_max_suppression,
        score_thresh=frcnn_config.first_stage_nms_score_threshold,
        iou_thresh=frcnn_config.first_stage_nms_iou_threshold,
        max_size_per_class=frcnn_config.first_stage_max_proposals,
        max_total_size=frcnn_config.first_stage_max_proposals,
        use_static_shapes=use_static_shapes and is_training)
    first_stage_loc_loss_weight = (
        frcnn_config.first_stage_localization_loss_weight)
    first_stage_obj_loss_weight = frcnn_config.first_stage_objectness_loss_weight

    initial_crop_size = frcnn_config.initial_crop_size
    maxpool_kernel_size = frcnn_config.maxpool_kernel_size
    maxpool_stride = frcnn_config.maxpool_stride

    second_stage_target_assigner = target_assigner.create_target_assigner(
        'FasterRCNN',
        'detection',
        use_matmul_gather=frcnn_config.use_matmul_gather_in_matcher)
    second_stage_box_predictor = box_predictor_builder.build(
        hyperparams_builder.build,
        frcnn_config.second_stage_box_predictor,
        is_training=is_training,
        num_classes=num_classes)
    second_stage_batch_size = frcnn_config.second_stage_batch_size
    second_stage_sampler = sampler.BalancedPositiveNegativeSampler(
        positive_fraction=frcnn_config.second_stage_balance_fraction,
        is_static=frcnn_config.use_static_balanced_label_sampler and is_training)
    (second_stage_non_max_suppression_fn, second_stage_score_conversion_fn
     ) = post_processing_builder.build(frcnn_config.second_stage_post_processing)
    second_stage_localization_loss_weight = (
        frcnn_config.second_stage_localization_loss_weight)
    second_stage_classification_loss = (
        losses_builder.build_faster_rcnn_classification_loss(
            frcnn_config.second_stage_classification_loss))
    second_stage_classification_loss_weight = (
        frcnn_config.second_stage_classification_loss_weight)
    second_stage_mask_prediction_loss_weight = (
        frcnn_config.second_stage_mask_prediction_loss_weight)

    hard_example_miner = None
    if frcnn_config.HasField('hard_example_miner'):
        hard_example_miner = losses_builder.build_hard_example_miner(
            frcnn_config.hard_example_miner,
            second_stage_classification_loss_weight,
            second_stage_localization_loss_weight)

    crop_and_resize_fn = (
        ops.matmul_crop_and_resize if frcnn_config.use_matmul_crop_and_resize
        else ops.native_crop_and_resize)
    clip_anchors_to_image = (
        frcnn_config.clip_anchors_to_image)

    common_kwargs = {
        'is_training': is_training,
        'num_classes': num_classes,
        'image_resizer_fn': image_resizer_fn,
        'feature_extractor': feature_extractor,
        'number_of_stages': number_of_stages,
        'first_stage_anchor_generator': first_stage_anchor_generator,
        'first_stage_target_assigner': first_stage_target_assigner,
        'first_stage_atrous_rate': first_stage_atrous_rate,
        'first_stage_box_predictor_arg_scope_fn':
            first_stage_box_predictor_arg_scope_fn,
        'first_stage_box_predictor_kernel_size':
            first_stage_box_predictor_kernel_size,
        'first_stage_box_predictor_depth': first_stage_box_predictor_depth,
        'first_stage_minibatch_size': first_stage_minibatch_size,
        'first_stage_sampler': first_stage_sampler,
        'first_stage_non_max_suppression_fn': first_stage_non_max_suppression_fn,
        'first_stage_max_proposals': first_stage_max_proposals,
        'first_stage_localization_loss_weight': first_stage_loc_loss_weight,
        'first_stage_objectness_loss_weight': first_stage_obj_loss_weight,
        'second_stage_target_assigner': second_stage_target_assigner,
        'second_stage_batch_size': second_stage_batch_size,
        'second_stage_sampler': second_stage_sampler,
        'second_stage_non_max_suppression_fn':
            second_stage_non_max_suppression_fn,
        'second_stage_score_conversion_fn': second_stage_score_conversion_fn,
        'second_stage_localization_loss_weight':
            second_stage_localization_loss_weight,
        'second_stage_classification_loss':
            second_stage_classification_loss,
        'second_stage_classification_loss_weight':
            second_stage_classification_loss_weight,
        'hard_example_miner': hard_example_miner,
        'add_summaries': add_summaries,
        'crop_and_resize_fn': crop_and_resize_fn,
        'clip_anchors_to_image': clip_anchors_to_image,
        'use_static_shapes': use_static_shapes,
        'resize_masks': frcnn_config.resize_masks
    }

    if isinstance(second_stage_box_predictor,
                  rfcn_box_predictor.RfcnBoxPredictor):
        return rfcn_meta_arch.RFCNMetaArch(
            second_stage_rfcn_box_predictor=second_stage_box_predictor,
            **common_kwargs)
    else:
        return faster_rcnn_meta_arch.FasterRCNNMetaArch(
            initial_crop_size=initial_crop_size,
            maxpool_kernel_size=maxpool_kernel_size,
            maxpool_stride=maxpool_stride,
            second_stage_mask_rcnn_box_predictor=second_stage_box_predictor,
            second_stage_mask_prediction_loss_weight=(
                second_stage_mask_prediction_loss_weight),
            **common_kwargs)