Esempio n. 1
0
    def __init__(self,
                 num_classes=80,
                 in_channels=(512, 1024, 512, 256, 256, 256),
                 anchor_generator=dict(type='SSDAnchorGenerator',
                                       scale_major=False,
                                       input_size=300,
                                       strides=[8, 16, 32, 64, 100, 300],
                                       ratios=([2], [2,
                                                     3], [2,
                                                          3], [2,
                                                               3], [2], [2]),
                                       basesize_ratio_range=(0.1, 0.9)),
                 bbox_coder=dict(
                     type='DeltaXYWHBBoxCoder',
                     target_means=[.0, .0, .0, .0],
                     target_stds=[1.0, 1.0, 1.0, 1.0],
                 ),
                 reg_decoded_bbox=False,
                 train_cfg=None,
                 test_cfg=None):
        super(AnchorHead, self).__init__()
        self.num_classes = num_classes
        self.in_channels = in_channels
        self.cls_out_channels = num_classes + 1  # add background class
        self.anchor_generator = build_anchor_generator(anchor_generator)
        num_anchors = self.anchor_generator.num_base_anchors

        reg_convs = []
        cls_convs = []
        for i in range(len(in_channels)):
            reg_convs.append(
                nn.Conv2d(in_channels[i],
                          num_anchors[i] * 4,
                          kernel_size=3,
                          padding=1))
            cls_convs.append(
                nn.Conv2d(in_channels[i],
                          num_anchors[i] * (num_classes + 1),
                          kernel_size=3,
                          padding=1))
        self.reg_convs = nn.ModuleList(reg_convs)
        self.cls_convs = nn.ModuleList(cls_convs)

        self.bbox_coder = build_bbox_coder(bbox_coder)
        self.reg_decoded_bbox = reg_decoded_bbox
        self.use_sigmoid_cls = False
        self.cls_focal_loss = False
        self.train_cfg = train_cfg
        self.test_cfg = test_cfg
        # set sampling=False for archor_target
        self.sampling = False
        self.debug = False
        if self.train_cfg:
            self.assigner = build_assigner(self.train_cfg.assigner)
            # SSD sampling=False so use PseudoSampler
            sampler_cfg = dict(type='PseudoSampler')
            self.sampler = build_sampler(sampler_cfg, context=self)
            self.debug = self.train_cfg.debug
        self.fp16_enabled = False
Esempio n. 2
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    def __init__(self,
                 with_avg_pool=False,
                 with_cls=True,
                 with_reg=True,
                 roi_feat_size=7,
                 in_channels=256,
                 num_classes=80,
                 bbox_coder=dict(type='DeltaXYWHBBoxCoder',
                                 target_means=[0., 0., 0., 0.],
                                 target_stds=[0.1, 0.1, 0.2, 0.2]),
                 reg_class_agnostic=False,
                 reg_decoded_bbox=False,
                 loss_cls=dict(type='CrossEntropyLoss',
                               use_sigmoid=False,
                               loss_weight=1.0),
                 loss_bbox=dict(type='SmoothL1Loss', beta=1.0,
                                loss_weight=1.0)):
        super(BBoxHead, self).__init__()
        assert with_cls or with_reg
        self.with_avg_pool = with_avg_pool
        self.with_cls = with_cls
        self.with_reg = with_reg
        self.roi_feat_size = _pair(roi_feat_size)
        self.roi_feat_area = self.roi_feat_size[0] * self.roi_feat_size[1]
        self.in_channels = in_channels
        self.num_classes = num_classes
        self.reg_class_agnostic = reg_class_agnostic
        self.reg_decoded_bbox = reg_decoded_bbox
        self.fp16_enabled = False

        self.bbox_coder = build_bbox_coder(bbox_coder)
        self.loss_cls = build_loss(loss_cls)
        self.loss_bbox = build_loss(loss_bbox)

        in_channels = self.in_channels
        if self.with_avg_pool:
            self.avg_pool = nn.AvgPool2d(self.roi_feat_size)
        else:
            in_channels *= self.roi_feat_area
        if self.with_cls:
            # need to add background class
            self.fc_cls = nn.Linear(in_channels, num_classes + 1)
        if self.with_reg:
            out_dim_reg = 4 if reg_class_agnostic else 4 * num_classes
            self.fc_reg = nn.Linear(in_channels, out_dim_reg)
        self.debug_imgs = None
Esempio n. 3
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    def __init__(
            self,
            num_classes,
            in_channels,
            feat_channels=256,
            approx_anchor_generator=dict(
                type='AnchorGenerator',
                octave_base_scale=8,
                scales_per_octave=3,
                ratios=[0.5, 1.0, 2.0],
                strides=[4, 8, 16, 32, 64]),
            square_anchor_generator=dict(
                type='AnchorGenerator',
                ratios=[1.0],
                scales=[8],
                strides=[4, 8, 16, 32, 64]),
            anchor_coder=dict(
                type='DeltaXYWHBBoxCoder',
                target_means=[.0, .0, .0, .0],
                target_stds=[1.0, 1.0, 1.0, 1.0]
            ),
            bbox_coder=dict(
                type='DeltaXYWHBBoxCoder',
                target_means=[.0, .0, .0, .0],
                target_stds=[1.0, 1.0, 1.0, 1.0]
            ),
            reg_decoded_bbox=False,
            deform_groups=4,
            loc_filter_thr=0.01,
            train_cfg=None,
            test_cfg=None,
            loss_loc=dict(
                type='FocalLoss',
                use_sigmoid=True,
                gamma=2.0,
                alpha=0.25,
                loss_weight=1.0),
            loss_shape=dict(type='BoundedIoULoss', beta=0.2, loss_weight=1.0),
            loss_cls=dict(
                type='CrossEntropyLoss', use_sigmoid=True, loss_weight=1.0),
            loss_bbox=dict(type='SmoothL1Loss', beta=1.0,
                           loss_weight=1.0)):  # yapf: disable
        super(AnchorHead, self).__init__()
        self.in_channels = in_channels
        self.num_classes = num_classes
        self.feat_channels = feat_channels
        self.deform_groups = deform_groups
        self.loc_filter_thr = loc_filter_thr

        # build approx_anchor_generator and square_anchor_generator
        assert (approx_anchor_generator['octave_base_scale'] ==
                square_anchor_generator['scales'][0])
        assert (approx_anchor_generator['strides'] ==
                square_anchor_generator['strides'])
        self.approx_anchor_generator = build_anchor_generator(
            approx_anchor_generator)
        self.square_anchor_generator = build_anchor_generator(
            square_anchor_generator)
        self.approxs_per_octave = self.approx_anchor_generator \
            .num_base_anchors[0]

        self.reg_decoded_bbox = reg_decoded_bbox

        # one anchor per location
        self.num_anchors = 1
        self.use_sigmoid_cls = loss_cls.get('use_sigmoid', False)
        self.loc_focal_loss = loss_loc['type'] in ['FocalLoss']
        self.sampling = loss_cls['type'] not in ['FocalLoss']
        self.ga_sampling = train_cfg is not None and hasattr(
            train_cfg, 'ga_sampler')
        if self.use_sigmoid_cls:
            self.cls_out_channels = self.num_classes
        else:
            self.cls_out_channels = self.num_classes + 1

        # build bbox_coder
        self.anchor_coder = build_bbox_coder(anchor_coder)
        self.bbox_coder = build_bbox_coder(bbox_coder)

        # build losses
        self.loss_loc = build_loss(loss_loc)
        self.loss_shape = build_loss(loss_shape)
        self.loss_cls = build_loss(loss_cls)
        self.loss_bbox = build_loss(loss_bbox)

        self.train_cfg = train_cfg
        self.test_cfg = test_cfg
        self.debug = False

        if self.train_cfg:
            self.assigner = build_assigner(self.train_cfg.assigner)
            # use PseudoSampler when sampling is False
            if self.sampling and hasattr(self.train_cfg, 'sampler'):
                sampler_cfg = self.train_cfg.sampler
            else:
                sampler_cfg = dict(type='PseudoSampler')
            self.sampler = build_sampler(sampler_cfg, context=self)

            self.ga_assigner = build_assigner(self.train_cfg.ga_assigner)
            if self.ga_sampling:
                ga_sampler_cfg = self.train_cfg.ga_sampler
            else:
                ga_sampler_cfg = dict(type='PseudoSampler')
            self.ga_sampler = build_sampler(ga_sampler_cfg, context=self)
            self.debug = self.train_cfg.debug

        self.fp16_enabled = False

        self._init_layers()
Esempio n. 4
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    def __init__(self,
                 num_classes,
                 cls_in_channels=256,
                 reg_in_channels=256,
                 roi_feat_size=7,
                 reg_feat_up_ratio=2,
                 reg_pre_kernel=3,
                 reg_post_kernel=3,
                 reg_pre_num=2,
                 reg_post_num=1,
                 cls_out_channels=1024,
                 reg_offset_out_channels=256,
                 reg_cls_out_channels=256,
                 num_cls_fcs=1,
                 num_reg_fcs=0,
                 reg_class_agnostic=True,
                 norm_cfg=None,
                 bbox_coder=dict(type='BucketingBBoxCoder',
                                 num_buckets=14,
                                 scale_factor=1.7),
                 loss_cls=dict(type='CrossEntropyLoss',
                               use_sigmoid=False,
                               loss_weight=1.0),
                 loss_bbox_cls=dict(type='CrossEntropyLoss',
                                    use_sigmoid=True,
                                    loss_weight=1.0),
                 loss_bbox_reg=dict(type='SmoothL1Loss',
                                    beta=0.1,
                                    loss_weight=1.0)):
        super(SABLHead, self).__init__()
        self.cls_in_channels = cls_in_channels
        self.reg_in_channels = reg_in_channels
        self.roi_feat_size = roi_feat_size
        self.reg_feat_up_ratio = int(reg_feat_up_ratio)
        self.num_buckets = bbox_coder['num_buckets']
        assert self.reg_feat_up_ratio // 2 >= 1
        self.up_reg_feat_size = roi_feat_size * self.reg_feat_up_ratio
        assert self.up_reg_feat_size == bbox_coder['num_buckets']
        self.reg_pre_kernel = reg_pre_kernel
        self.reg_post_kernel = reg_post_kernel
        self.reg_pre_num = reg_pre_num
        self.reg_post_num = reg_post_num
        self.num_classes = num_classes
        self.cls_out_channels = cls_out_channels
        self.reg_offset_out_channels = reg_offset_out_channels
        self.reg_cls_out_channels = reg_cls_out_channels
        self.num_cls_fcs = num_cls_fcs
        self.num_reg_fcs = num_reg_fcs
        self.reg_class_agnostic = reg_class_agnostic
        assert self.reg_class_agnostic
        self.norm_cfg = norm_cfg

        self.bbox_coder = build_bbox_coder(bbox_coder)
        self.loss_cls = build_loss(loss_cls)
        self.loss_bbox_cls = build_loss(loss_bbox_cls)
        self.loss_bbox_reg = build_loss(loss_bbox_reg)

        self.cls_fcs = self._add_fc_branch(self.num_cls_fcs,
                                           self.cls_in_channels,
                                           self.roi_feat_size,
                                           self.cls_out_channels)

        self.side_num = int(np.ceil(self.num_buckets / 2))

        if self.reg_feat_up_ratio > 1:
            self.upsample_x = nn.ConvTranspose1d(reg_in_channels,
                                                 reg_in_channels,
                                                 self.reg_feat_up_ratio,
                                                 stride=self.reg_feat_up_ratio)
            self.upsample_y = nn.ConvTranspose1d(reg_in_channels,
                                                 reg_in_channels,
                                                 self.reg_feat_up_ratio,
                                                 stride=self.reg_feat_up_ratio)

        self.reg_pre_convs = nn.ModuleList()
        for i in range(self.reg_pre_num):
            reg_pre_conv = ConvModule(reg_in_channels,
                                      reg_in_channels,
                                      kernel_size=reg_pre_kernel,
                                      padding=reg_pre_kernel // 2,
                                      norm_cfg=norm_cfg,
                                      act_cfg=dict(type='ReLU'))
            self.reg_pre_convs.append(reg_pre_conv)

        self.reg_post_conv_xs = nn.ModuleList()
        for i in range(self.reg_post_num):
            reg_post_conv_x = ConvModule(reg_in_channels,
                                         reg_in_channels,
                                         kernel_size=(1, reg_post_kernel),
                                         padding=(0, reg_post_kernel // 2),
                                         norm_cfg=norm_cfg,
                                         act_cfg=dict(type='ReLU'))
            self.reg_post_conv_xs.append(reg_post_conv_x)
        self.reg_post_conv_ys = nn.ModuleList()
        for i in range(self.reg_post_num):
            reg_post_conv_y = ConvModule(reg_in_channels,
                                         reg_in_channels,
                                         kernel_size=(reg_post_kernel, 1),
                                         padding=(reg_post_kernel // 2, 0),
                                         norm_cfg=norm_cfg,
                                         act_cfg=dict(type='ReLU'))
            self.reg_post_conv_ys.append(reg_post_conv_y)

        self.reg_conv_att_x = nn.Conv2d(reg_in_channels, 1, 1)
        self.reg_conv_att_y = nn.Conv2d(reg_in_channels, 1, 1)

        self.fc_cls = nn.Linear(self.cls_out_channels, self.num_classes + 1)
        self.relu = nn.ReLU(inplace=True)

        self.reg_cls_fcs = self._add_fc_branch(self.num_reg_fcs,
                                               self.reg_in_channels, 1,
                                               self.reg_cls_out_channels)
        self.reg_offset_fcs = self._add_fc_branch(self.num_reg_fcs,
                                                  self.reg_in_channels, 1,
                                                  self.reg_offset_out_channels)
        self.fc_reg_cls = nn.Linear(self.reg_cls_out_channels, 1)
        self.fc_reg_offset = nn.Linear(self.reg_offset_out_channels, 1)
Esempio n. 5
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    def __init__(self,
                 num_classes,
                 in_channels,
                 out_channels=(1024, 512, 256),
                 anchor_generator=dict(type='YOLOAnchorGenerator',
                                       base_sizes=[[(116, 90), (156, 198),
                                                    (373, 326)],
                                                   [(30, 61), (62, 45),
                                                    (59, 119)],
                                                   [(10, 13), (16, 30),
                                                    (33, 23)]],
                                       strides=[32, 16, 8]),
                 bbox_coder=dict(type='YOLOBBoxCoder'),
                 featmap_strides=[32, 16, 8],
                 one_hot_smoother=0.,
                 conv_cfg=None,
                 norm_cfg=dict(type='BN', requires_grad=True),
                 act_cfg=dict(type='LeakyReLU', negative_slope=0.1),
                 loss_cls=dict(type='CrossEntropyLoss',
                               use_sigmoid=True,
                               loss_weight=1.0),
                 loss_conf=dict(type='CrossEntropyLoss',
                                use_sigmoid=True,
                                loss_weight=1.0),
                 loss_xy=dict(type='CrossEntropyLoss',
                              use_sigmoid=True,
                              loss_weight=1.0),
                 loss_wh=dict(type='MSELoss', loss_weight=1.0),
                 train_cfg=None,
                 test_cfg=None):
        super(YOLOV3Head, self).__init__()
        # Check params
        assert (len(in_channels) == len(out_channels) == len(featmap_strides))

        self.num_classes = num_classes
        self.in_channels = in_channels
        self.out_channels = out_channels
        self.featmap_strides = featmap_strides
        self.train_cfg = train_cfg
        self.test_cfg = test_cfg
        self.debug = False
        if self.train_cfg:
            self.assigner = build_assigner(self.train_cfg.assigner)
            if hasattr(self.train_cfg, 'sampler'):
                sampler_cfg = self.train_cfg.sampler
            else:
                sampler_cfg = dict(type='PseudoSampler')  # yolo系列不需随机采样等操作
            self.sampler = build_sampler(sampler_cfg, context=self)
            self.debug = self.train_cfg.debug

        self.one_hot_smoother = one_hot_smoother

        self.conv_cfg = conv_cfg
        self.norm_cfg = norm_cfg
        self.act_cfg = act_cfg

        self.bbox_coder = build_bbox_coder(bbox_coder)
        self.anchor_generator = build_anchor_generator(anchor_generator)

        self.loss_cls = build_loss(loss_cls)
        self.loss_conf = build_loss(loss_conf)
        self.loss_xy = build_loss(loss_xy)
        self.loss_wh = build_loss(loss_wh)
        # usually the numbers of anchors for each level are the same
        # except SSD detectors
        self.num_anchors = self.anchor_generator.num_base_anchors[0]
        assert len(
            self.anchor_generator.num_base_anchors) == len(featmap_strides)
        self._init_layers()
Esempio n. 6
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    def __init__(self,
                 num_classes,
                 in_channels,
                 feat_channels=256,
                 anchor_generator=dict(
                     type='AnchorGenerator',
                     scales=[8, 16, 32],
                     ratios=[0.5, 1.0, 2.0],
                     strides=[4, 8, 16, 32, 64]),
                 bbox_coder=dict(
                     type='DeltaXYWHBBoxCoder',
                     target_means=(.0, .0, .0, .0),
                     target_stds=(1.0, 1.0, 1.0, 1.0)),
                 reg_decoded_bbox=False,
                 background_label=None,
                 loss_cls=dict(
                     type='CrossEntropyLoss',
                     use_sigmoid=True,
                     loss_weight=1.0),
                 loss_bbox=dict(
                     type='SmoothL1Loss', beta=1.0 / 9.0, loss_weight=1.0),
                 train_cfg=None,
                 test_cfg=None):
        super(AnchorHead, self).__init__()
        self.in_channels = in_channels
        self.num_classes = num_classes
        self.feat_channels = feat_channels
        self.use_sigmoid_cls = loss_cls.get('use_sigmoid', False)
        # TODO better way to determine whether sample or not
        self.sampling = loss_cls['type'] not in [
            'FocalLoss', 'GHMC', 'QualityFocalLoss'
        ]
        if self.use_sigmoid_cls:
            self.cls_out_channels = num_classes
        else:
            self.cls_out_channels = num_classes + 1

        if self.cls_out_channels <= 0:
            raise ValueError(f'num_classes={num_classes} is too small')
        self.reg_decoded_bbox = reg_decoded_bbox

        self.background_label = (
            num_classes if background_label is None else background_label)
        # background_label should be either 0 or num_classes
        assert (self.background_label == 0
                or self.background_label == num_classes)

        self.bbox_coder = build_bbox_coder(bbox_coder)
        self.loss_cls = build_loss(loss_cls)
        self.loss_bbox = build_loss(loss_bbox)
        self.train_cfg = train_cfg
        self.test_cfg = test_cfg
        self.debug = False
        if self.train_cfg:
            self.assigner = build_assigner(self.train_cfg.assigner)
            # use PseudoSampler when sampling is False
            if self.sampling and hasattr(self.train_cfg, 'sampler'):
                sampler_cfg = self.train_cfg.sampler
            else:
                sampler_cfg = dict(type='PseudoSampler')
            self.sampler = build_sampler(sampler_cfg, context=self)
            self.debug = self.train_cfg.debug
        self.fp16_enabled = False

        self.anchor_generator = build_anchor_generator(anchor_generator)
        # usually the numbers of anchors for each level are the same
        # except SSD detectors
        self.num_anchors = self.anchor_generator.num_base_anchors[0]
        self._init_layers()
    def __init__(self,
                 num_classes,
                 in_channels,
                 regress_ranges=((-1, 64), (64, 128), (128, 256), (256, 512),
                                 (512, INF)),
                 center_sampling=False,
                 center_sample_radius=1.5,
                 sync_num_pos=True,
                 gradient_mul=0.1,
                 bbox_norm_type='reg_denom',
                 loss_cls_fl=dict(type='FocalLoss',
                                  use_sigmoid=True,
                                  gamma=2.0,
                                  alpha=0.25,
                                  loss_weight=1.0),
                 use_vfl=True,
                 loss_cls=dict(type='VarifocalLoss',
                               use_sigmoid=True,
                               alpha=0.75,
                               gamma=2.0,
                               iou_weighted=True,
                               loss_weight=1.0),
                 loss_bbox=dict(type='GIoULoss', loss_weight=1.5),
                 loss_bbox_refine=dict(type='GIoULoss', loss_weight=2.0),
                 norm_cfg=dict(type='GN', num_groups=32, requires_grad=True),
                 use_atss=True,
                 bbox_coder=dict(type='DeltaXYWHBBoxCoder',
                                 target_means=[.0, .0, .0, .0],
                                 target_stds=[0.1, 0.1, 0.2, 0.2]),
                 anchor_generator=dict(type='AnchorGenerator',
                                       ratios=[1.0],
                                       octave_base_scale=8,
                                       scales_per_octave=1,
                                       center_offset=0.0,
                                       strides=[8, 16, 32, 64, 128]),
                 **kwargs):

        self.bbox_coder = build_bbox_coder(bbox_coder)
        # dcn base offsets, adapted from reppoints_head.py
        self.num_dconv_points = 9
        self.dcn_kernel = int(np.sqrt(self.num_dconv_points))
        self.dcn_pad = int((self.dcn_kernel - 1) / 2)
        dcn_base = np.arange(-self.dcn_pad,
                             self.dcn_pad + 1).astype(np.float64)
        dcn_base_y = np.repeat(dcn_base, self.dcn_kernel)
        dcn_base_x = np.tile(dcn_base, self.dcn_kernel)
        dcn_base_offset = np.stack([dcn_base_y, dcn_base_x], axis=1).reshape(
            (-1))
        # 3x3的位置offset
        self.dcn_base_offset = torch.tensor(dcn_base_offset).view(1, -1, 1, 1)

        super(FCOSHead, self).__init__(num_classes,
                                       in_channels,
                                       norm_cfg=norm_cfg,
                                       **kwargs)
        self.regress_ranges = regress_ranges
        self.reg_denoms = [
            regress_range[-1] for regress_range in regress_ranges
        ]
        self.reg_denoms[-1] = self.reg_denoms[-2] * 2
        self.center_sampling = center_sampling
        self.center_sample_radius = center_sample_radius
        self.sync_num_pos = sync_num_pos
        self.bbox_norm_type = bbox_norm_type
        self.gradient_mul = gradient_mul
        self.use_vfl = use_vfl
        if self.use_vfl:
            self.loss_cls = build_loss(loss_cls)
        else:
            self.loss_cls = build_loss(loss_cls_fl)
        self.loss_bbox = build_loss(loss_bbox)
        self.loss_bbox_refine = build_loss(loss_bbox_refine)

        # for getting ATSS targets
        self.use_atss = use_atss
        self.use_sigmoid_cls = loss_cls.get('use_sigmoid', False)
        self.anchor_generator = build_anchor_generator(anchor_generator)
        self.anchor_center_offset = anchor_generator['center_offset']
        self.num_anchors = self.anchor_generator.num_base_anchors[0]
        self.sampling = False
        self.debug = False
        if self.train_cfg:
            self.assigner = build_assigner(self.train_cfg.assigner)
            sampler_cfg = dict(type='PseudoSampler')
            self.sampler = build_sampler(sampler_cfg, context=self)
            self.debug = self.train_cfg.debug
    def __init__(self,
                 num_classes,
                 in_channels,
                 stacked_convs=4,
                 feat_channels=256,
                 approx_anchor_generator=dict(type='AnchorGenerator',
                                              octave_base_scale=4,
                                              scales_per_octave=3,
                                              ratios=[0.5, 1.0, 2.0],
                                              strides=[8, 16, 32, 64, 128]),
                 square_anchor_generator=dict(type='AnchorGenerator',
                                              ratios=[1.0],
                                              scales=[4],
                                              strides=[8, 16, 32, 64, 128]),
                 conv_cfg=None,
                 norm_cfg=None,
                 bbox_coder=dict(type='BucketingBBoxCoder',
                                 num_buckets=14,
                                 scale_factor=3.0),
                 reg_decoded_bbox=False,
                 train_cfg=None,
                 test_cfg=None,
                 loss_cls=dict(type='FocalLoss',
                               use_sigmoid=True,
                               gamma=2.0,
                               alpha=0.25,
                               loss_weight=1.0),
                 loss_bbox_cls=dict(type='CrossEntropyLoss',
                                    use_sigmoid=True,
                                    loss_weight=1.5),
                 loss_bbox_reg=dict(type='SmoothL1Loss',
                                    beta=1.0 / 9.0,
                                    loss_weight=1.5)):
        super(SABLRetinaHead, self).__init__()
        self.in_channels = in_channels
        self.num_classes = num_classes
        self.feat_channels = feat_channels
        self.num_buckets = bbox_coder['num_buckets']
        self.side_num = int(np.ceil(self.num_buckets / 2))

        assert (approx_anchor_generator['octave_base_scale'] ==
                square_anchor_generator['scales'][0])
        assert (approx_anchor_generator['strides'] ==
                square_anchor_generator['strides'])

        self.approx_anchor_generator = build_anchor_generator(
            approx_anchor_generator)
        self.square_anchor_generator = build_anchor_generator(
            square_anchor_generator)
        self.approxs_per_octave = (
            self.approx_anchor_generator.num_base_anchors[0])

        # one anchor per location
        self.num_anchors = 1
        self.stacked_convs = stacked_convs
        self.conv_cfg = conv_cfg
        self.norm_cfg = norm_cfg

        self.reg_decoded_bbox = reg_decoded_bbox

        self.use_sigmoid_cls = loss_cls.get('use_sigmoid', False)
        self.sampling = loss_cls['type'] not in [
            'FocalLoss', 'GHMC', 'QualityFocalLoss'
        ]
        if self.use_sigmoid_cls:
            self.cls_out_channels = num_classes
        else:
            self.cls_out_channels = num_classes + 1

        self.bbox_coder = build_bbox_coder(bbox_coder)
        self.loss_cls = build_loss(loss_cls)
        self.loss_bbox_cls = build_loss(loss_bbox_cls)
        self.loss_bbox_reg = build_loss(loss_bbox_reg)

        self.train_cfg = train_cfg
        self.test_cfg = test_cfg
        self.debug = False

        if self.train_cfg:
            self.assigner = build_assigner(self.train_cfg.assigner)
            # use PseudoSampler when sampling is False
            if self.sampling and hasattr(self.train_cfg, 'sampler'):
                sampler_cfg = self.train_cfg.sampler
            else:
                sampler_cfg = dict(type='PseudoSampler')
            self.sampler = build_sampler(sampler_cfg, context=self)
            self.debug = self.train_cfg.debug

        self.fp16_enabled = False
        self._init_layers()