# Copyright (c) OpenMMLab. All rights reserved. import torch from mmcv.cnn import xavier_init from torch import nn as nn from mmdet3d.core.utils import get_ellip_gaussian_2D from mmdet3d.models.model_utils import EdgeFusionModule from mmdet3d.models.utils import (filter_outside_objs, get_edge_indices, get_keypoints, handle_proj_objs) from mmdet.core import multi_apply from mmdet.core.bbox.builder import build_bbox_coder from mmdet.models.builder import HEADS, build_loss from mmdet.models.utils import gaussian_radius, gen_gaussian_target from mmdet.models.utils.gaussian_target import (get_local_maximum, get_topk_from_heatmap, transpose_and_gather_feat) from .anchor_free_mono3d_head import AnchorFreeMono3DHead @HEADS.register_module() class MonoFlexHead(AnchorFreeMono3DHead): r"""MonoFlex head used in `MonoFlex `_ .. code-block:: none / --> 3 x 3 conv --> 1 x 1 conv --> [edge fusion] --> cls | | --> 3 x 3 conv --> 1 x 1 conv --> 2d bbox | | --> 3 x 3 conv --> 1 x 1 conv --> [edge fusion] --> 2d offsets | | --> 3 x 3 conv --> 1 x 1 conv --> keypoints offsets | | --> 3 x 3 conv --> 1 x 1 conv --> keypoints uncertainty feature | --> 3 x 3 conv --> 1 x 1 conv --> keypoints uncertainty | | --> 3 x 3 conv --> 1 x 1 conv --> 3d dimensions | | |--- 1 x 1 conv --> ori cls | --> 3 x 3 conv --| | |--- 1 x 1 conv --> ori offsets | | --> 3 x 3 conv --> 1 x 1 conv --> depth | \ --> 3 x 3 conv --> 1 x 1 conv --> depth uncertainty Args: use_edge_fusion (bool): Whether to use edge fusion module while feature extraction. edge_fusion_inds (list[tuple]): Indices of feature to use edge fusion. edge_heatmap_ratio (float): Ratio of generating target heatmap. filter_outside_objs (bool, optional): Whether to filter the outside objects. Default: True. loss_cls (dict, optional): Config of classification loss. Default: loss_cls=dict(type='GaussionFocalLoss', loss_weight=1.0). loss_bbox (dict, optional): Config of localization loss. Default: loss_bbox=dict(type='IOULoss', loss_weight=10.0). loss_dir (dict, optional): Config of direction classification loss. Default: dict(type='MultibinLoss', loss_weight=0.1). loss_keypoints (dict, optional): Config of keypoints loss. Default: dict(type='L1Loss', loss_weight=0.1). loss_dims: (dict, optional): Config of dimensions loss. Default: dict(type='L1Loss', loss_weight=0.1). loss_offsets2d: (dict, optional): Config of offsets2d loss. Default: dict(type='L1Loss', loss_weight=0.1). loss_direct_depth: (dict, optional): Config of directly regression depth loss. Default: dict(type='L1Loss', loss_weight=0.1). loss_keypoints_depth: (dict, optional): Config of keypoints decoded depth loss. Default: dict(type='L1Loss', loss_weight=0.1). loss_combined_depth: (dict, optional): Config of combined depth loss. Default: dict(type='L1Loss', loss_weight=0.1). loss_attr (dict, optional): Config of attribute classification loss. In MonoFlex, Default: None. bbox_coder (dict, optional): Bbox coder for encoding and decoding boxes. Default: dict(type='MonoFlexCoder', code_size=7). norm_cfg (dict, optional): Dictionary to construct and config norm layer. Default: norm_cfg=dict(type='GN', num_groups=32, requires_grad=True). init_cfg (dict): Initialization config dict. Default: None. """ # noqa: E501 def __init__(self, num_classes, in_channels, use_edge_fusion, edge_fusion_inds, edge_heatmap_ratio, filter_outside_objs=True, loss_cls=dict(type='GaussianFocalLoss', loss_weight=1.0), loss_bbox=dict(type='IoULoss', loss_weight=0.1), loss_dir=dict(type='MultiBinLoss', loss_weight=0.1), loss_keypoints=dict(type='L1Loss', loss_weight=0.1), loss_dims=dict(type='L1Loss', loss_weight=0.1), loss_offsets2d=dict(type='L1Loss', loss_weight=0.1), loss_direct_depth=dict(type='L1Loss', loss_weight=0.1), loss_keypoints_depth=dict(type='L1Loss', loss_weight=0.1), loss_combined_depth=dict(type='L1Loss', loss_weight=0.1), loss_attr=None, bbox_coder=dict(type='MonoFlexCoder', code_size=7), norm_cfg=dict(type='BN'), init_cfg=None, init_bias=-2.19, **kwargs): self.use_edge_fusion = use_edge_fusion self.edge_fusion_inds = edge_fusion_inds super().__init__( num_classes, in_channels, loss_cls=loss_cls, loss_bbox=loss_bbox, loss_dir=loss_dir, loss_attr=loss_attr, norm_cfg=norm_cfg, init_cfg=init_cfg, **kwargs) self.filter_outside_objs = filter_outside_objs self.edge_heatmap_ratio = edge_heatmap_ratio self.init_bias = init_bias self.loss_dir = build_loss(loss_dir) self.loss_keypoints = build_loss(loss_keypoints) self.loss_dims = build_loss(loss_dims) self.loss_offsets2d = build_loss(loss_offsets2d) self.loss_direct_depth = build_loss(loss_direct_depth) self.loss_keypoints_depth = build_loss(loss_keypoints_depth) self.loss_combined_depth = build_loss(loss_combined_depth) self.bbox_coder = build_bbox_coder(bbox_coder) def _init_edge_module(self): """Initialize edge fusion module for feature extraction.""" self.edge_fuse_cls = EdgeFusionModule(self.num_classes, 256) for i in range(len(self.edge_fusion_inds)): reg_inds, out_inds = self.edge_fusion_inds[i] out_channels = self.group_reg_dims[reg_inds][out_inds] fusion_layer = EdgeFusionModule(out_channels, 256) layer_name = f'edge_fuse_reg_{reg_inds}_{out_inds}' self.add_module(layer_name, fusion_layer) def init_weights(self): """Initialize weights.""" super().init_weights() self.conv_cls.bias.data.fill_(self.init_bias) xavier_init(self.conv_regs[4][0], gain=0.01) xavier_init(self.conv_regs[7][0], gain=0.01) for m in self.conv_regs.modules(): if isinstance(m, nn.Conv2d): if m.bias is not None: nn.init.constant_(m.bias, 0) def _init_predictor(self): """Initialize predictor layers of the head.""" self.conv_cls_prev = self._init_branch( conv_channels=self.cls_branch, conv_strides=(1, ) * len(self.cls_branch)) self.conv_cls = nn.Conv2d(self.cls_branch[-1], self.cls_out_channels, 1) # init regression head self.conv_reg_prevs = nn.ModuleList() # init output head self.conv_regs = nn.ModuleList() # group_reg_dims: # ((4, ), (2, ), (20, ), (3, ), (3, ), (8, 8), (1, ), (1, )) for i in range(len(self.group_reg_dims)): reg_dims = self.group_reg_dims[i] reg_branch_channels = self.reg_branch[i] out_channel = self.out_channels[i] reg_list = nn.ModuleList() if len(reg_branch_channels) > 0: self.conv_reg_prevs.append( self._init_branch( conv_channels=reg_branch_channels, conv_strides=(1, ) * len(reg_branch_channels))) for reg_dim in reg_dims: reg_list.append(nn.Conv2d(out_channel, reg_dim, 1)) self.conv_regs.append(reg_list) else: self.conv_reg_prevs.append(None) for reg_dim in reg_dims: reg_list.append(nn.Conv2d(self.feat_channels, reg_dim, 1)) self.conv_regs.append(reg_list) def _init_layers(self): """Initialize layers of the head.""" self._init_predictor() if self.use_edge_fusion: self._init_edge_module() def forward_train(self, x, input_metas, gt_bboxes, gt_labels, gt_bboxes_3d, gt_labels_3d, centers2d, depths, attr_labels, gt_bboxes_ignore, proposal_cfg, **kwargs): """ Args: x (list[Tensor]): Features from FPN. input_metas (list[dict]): Meta information of each image, e.g., image size, scaling factor, etc. gt_bboxes (list[Tensor]): Ground truth bboxes of the image, shape (num_gts, 4). gt_labels (list[Tensor]): Ground truth labels of each box, shape (num_gts,). gt_bboxes_3d (list[Tensor]): 3D ground truth bboxes of the image, shape (num_gts, self.bbox_code_size). gt_labels_3d (list[Tensor]): 3D ground truth labels of each box, shape (num_gts,). centers2d (list[Tensor]): Projected 3D center of each box, shape (num_gts, 2). depths (list[Tensor]): Depth of projected 3D center of each box, shape (num_gts,). attr_labels (list[Tensor]): Attribute labels of each box, shape (num_gts,). gt_bboxes_ignore (list[Tensor]): Ground truth bboxes to be ignored, shape (num_ignored_gts, 4). proposal_cfg (mmcv.Config): Test / postprocessing configuration, if None, test_cfg would be used Returns: tuple: losses: (dict[str, Tensor]): A dictionary of loss components. proposal_list (list[Tensor]): Proposals of each image. """ outs = self(x, input_metas) if gt_labels is None: loss_inputs = outs + (gt_bboxes, gt_bboxes_3d, centers2d, depths, attr_labels, input_metas) else: loss_inputs = outs + (gt_bboxes, gt_labels, gt_bboxes_3d, gt_labels_3d, centers2d, depths, attr_labels, input_metas) losses = self.loss(*loss_inputs, gt_bboxes_ignore=gt_bboxes_ignore) if proposal_cfg is None: return losses else: proposal_list = self.get_bboxes( *outs, input_metas, cfg=proposal_cfg) return losses, proposal_list def forward(self, feats, input_metas): """Forward features from the upstream network. Args: feats (list[Tensor]): Features from the upstream network, each is a 4D-tensor. input_metas (list[dict]): Meta information of each image, e.g., image size, scaling factor, etc. Returns: tuple: cls_scores (list[Tensor]): Box scores for each scale level, each is a 4D-tensor, the channel number is num_points * num_classes. bbox_preds (list[Tensor]): Box energies / deltas for each scale level, each is a 4D-tensor, the channel number is num_points * bbox_code_size. """ mlvl_input_metas = [input_metas for i in range(len(feats))] return multi_apply(self.forward_single, feats, mlvl_input_metas) def forward_single(self, x, input_metas): """Forward features of a single scale level. Args: x (Tensor): Feature maps from a specific FPN feature level. input_metas (list[dict]): Meta information of each image, e.g., image size, scaling factor, etc. Returns: tuple: Scores for each class, bbox predictions. """ img_h, img_w = input_metas[0]['pad_shape'][:2] batch_size, _, feat_h, feat_w = x.shape downsample_ratio = img_h / feat_h for conv_cls_prev_layer in self.conv_cls_prev: cls_feat = conv_cls_prev_layer(x) out_cls = self.conv_cls(cls_feat) if self.use_edge_fusion: # calculate the edge indices for the batch data edge_indices_list = get_edge_indices( input_metas, downsample_ratio, device=x.device) edge_lens = [ edge_indices.shape[0] for edge_indices in edge_indices_list ] max_edge_len = max(edge_lens) edge_indices = x.new_zeros((batch_size, max_edge_len, 2), dtype=torch.long) for i in range(batch_size): edge_indices[i, :edge_lens[i]] = edge_indices_list[i] # cls feature map edge fusion out_cls = self.edge_fuse_cls(cls_feat, out_cls, edge_indices, edge_lens, feat_h, feat_w) bbox_pred = [] for i in range(len(self.group_reg_dims)): reg_feat = x.clone() # feature regression head if len(self.reg_branch[i]) > 0: for conv_reg_prev_layer in self.conv_reg_prevs[i]: reg_feat = conv_reg_prev_layer(reg_feat) for j, conv_reg in enumerate(self.conv_regs[i]): out_reg = conv_reg(reg_feat) # Use Edge Fusion Module if self.use_edge_fusion and (i, j) in self.edge_fusion_inds: # reg feature map edge fusion out_reg = getattr(self, 'edge_fuse_reg_{}_{}'.format( i, j))(reg_feat, out_reg, edge_indices, edge_lens, feat_h, feat_w) bbox_pred.append(out_reg) bbox_pred = torch.cat(bbox_pred, dim=1) cls_score = out_cls.sigmoid() # turn to 0-1 cls_score = cls_score.clamp(min=1e-4, max=1 - 1e-4) return cls_score, bbox_pred def get_bboxes(self, cls_scores, bbox_preds, input_metas): """Generate bboxes from bbox head predictions. Args: cls_scores (list[Tensor]): Box scores for each scale level. bbox_preds (list[Tensor]): Box regression for each scale. input_metas (list[dict]): Meta information of each image, e.g., image size, scaling factor, etc. rescale (bool): If True, return boxes in original image space. Returns: list[tuple[:obj:`CameraInstance3DBoxes`, Tensor, Tensor, None]]: Each item in result_list is 4-tuple. """ assert len(cls_scores) == len(bbox_preds) == 1 cam2imgs = torch.stack([ cls_scores[0].new_tensor(input_meta['cam2img']) for input_meta in input_metas ]) batch_bboxes, batch_scores, batch_topk_labels = self.decode_heatmap( cls_scores[0], bbox_preds[0], input_metas, cam2imgs=cam2imgs, topk=100, kernel=3) result_list = [] for img_id in range(len(input_metas)): bboxes = batch_bboxes[img_id] scores = batch_scores[img_id] labels = batch_topk_labels[img_id] keep_idx = scores > 0.25 bboxes = bboxes[keep_idx] scores = scores[keep_idx] labels = labels[keep_idx] bboxes = input_metas[img_id]['box_type_3d']( bboxes, box_dim=self.bbox_code_size, origin=(0.5, 0.5, 0.5)) attrs = None result_list.append((bboxes, scores, labels, attrs)) return result_list def decode_heatmap(self, cls_score, reg_pred, input_metas, cam2imgs, topk=100, kernel=3): """Transform outputs into detections raw bbox predictions. Args: class_score (Tensor): Center predict heatmap, shape (B, num_classes, H, W). reg_pred (Tensor): Box regression map. shape (B, channel, H , W). input_metas (List[dict]): Meta information of each image, e.g., image size, scaling factor, etc. cam2imgs (Tensor): Camera intrinsic matrix. shape (N, 4, 4) topk (int, optional): Get top k center keypoints from heatmap. Default 100. kernel (int, optional): Max pooling kernel for extract local maximum pixels. Default 3. Returns: tuple[torch.Tensor]: Decoded output of SMOKEHead, containing the following Tensors: - batch_bboxes (Tensor): Coords of each 3D box. shape (B, k, 7) - batch_scores (Tensor): Scores of each 3D box. shape (B, k) - batch_topk_labels (Tensor): Categories of each 3D box. shape (B, k) """ img_h, img_w = input_metas[0]['pad_shape'][:2] batch_size, _, feat_h, feat_w = cls_score.shape downsample_ratio = img_h / feat_h center_heatmap_pred = get_local_maximum(cls_score, kernel=kernel) *batch_dets, topk_ys, topk_xs = get_topk_from_heatmap( center_heatmap_pred, k=topk) batch_scores, batch_index, batch_topk_labels = batch_dets regression = transpose_and_gather_feat(reg_pred, batch_index) regression = regression.view(-1, 8) pred_base_centers2d = torch.cat( [topk_xs.view(-1, 1), topk_ys.view(-1, 1).float()], dim=1) preds = self.bbox_coder.decode(regression, batch_topk_labels, downsample_ratio, cam2imgs) pred_locations = self.bbox_coder.decode_location( pred_base_centers2d, preds['offsets2d'], preds['combined_depth'], cam2imgs, downsample_ratio) pred_yaws = self.bbox_coder.decode_orientation( preds['orientations']).unsqueeze(-1) pred_dims = preds['dimensions'] batch_bboxes = torch.cat((pred_locations, pred_dims, pred_yaws), dim=1) batch_bboxes = batch_bboxes.view(batch_size, -1, self.bbox_code_size) return batch_bboxes, batch_scores, batch_topk_labels def get_predictions(self, pred_reg, labels3d, centers2d, reg_mask, batch_indices, input_metas, downsample_ratio): """Prepare predictions for computing loss. Args: pred_reg (Tensor): Box regression map. shape (B, channel, H , W). labels3d (Tensor): Labels of each 3D box. shape (B * max_objs, ) centers2d (Tensor): Coords of each projected 3D box center on image. shape (N, 2) reg_mask (Tensor): Indexes of the existence of the 3D box. shape (B * max_objs, ) batch_indices (Tenosr): Batch indices of the 3D box. shape (N, 3) input_metas (list[dict]): Meta information of each image, e.g., image size, scaling factor, etc. downsample_ratio (int): The stride of feature map. Returns: dict: The predictions for computing loss. """ batch, channel = pred_reg.shape[0], pred_reg.shape[1] w = pred_reg.shape[3] cam2imgs = torch.stack([ centers2d.new_tensor(input_meta['cam2img']) for input_meta in input_metas ]) # (batch_size, 4, 4) -> (N, 4, 4) cam2imgs = cam2imgs[batch_indices, :, :] centers2d_inds = centers2d[:, 1] * w + centers2d[:, 0] centers2d_inds = centers2d_inds.view(batch, -1) pred_regression = transpose_and_gather_feat(pred_reg, centers2d_inds) pred_regression_pois = pred_regression.view(-1, channel)[reg_mask] preds = self.bbox_coder.decode(pred_regression_pois, labels3d, downsample_ratio, cam2imgs) return preds def get_targets(self, gt_bboxes_list, gt_labels_list, gt_bboxes_3d_list, gt_labels_3d_list, centers2d_list, depths_list, feat_shape, img_shape, input_metas): """Get training targets for batch images. `` Args: gt_bboxes_list (list[Tensor]): Ground truth bboxes of each image, shape (num_gt, 4). gt_labels_list (list[Tensor]): Ground truth labels of each box, shape (num_gt,). gt_bboxes_3d_list (list[:obj:`CameraInstance3DBoxes`]): 3D Ground truth bboxes of each image, shape (num_gt, bbox_code_size). gt_labels_3d_list (list[Tensor]): 3D Ground truth labels of each box, shape (num_gt,). centers2d_list (list[Tensor]): Projected 3D centers onto 2D image, shape (num_gt, 2). depths_list (list[Tensor]): Depth of projected 3D centers onto 2D image, each has shape (num_gt, 1). feat_shape (tuple[int]): Feature map shape with value, shape (B, _, H, W). img_shape (tuple[int]): Image shape in [h, w] format. input_metas (list[dict]): Meta information of each image, e.g., image size, scaling factor, etc. Returns: tuple[Tensor, dict]: The Tensor value is the targets of center heatmap, the dict has components below: - base_centers2d_target (Tensor): Coords of each projected 3D box center on image. shape (B * max_objs, 2), [dtype: int] - labels3d (Tensor): Labels of each 3D box. shape (N, ) - reg_mask (Tensor): Mask of the existence of the 3D box. shape (B * max_objs, ) - batch_indices (Tensor): Batch id of the 3D box. shape (N, ) - depth_target (Tensor): Depth target of each 3D box. shape (N, ) - keypoints2d_target (Tensor): Keypoints of each projected 3D box on image. shape (N, 10, 2) - keypoints_mask (Tensor): Keypoints mask of each projected 3D box on image. shape (N, 10) - keypoints_depth_mask (Tensor): Depths decoded from keypoints of each 3D box. shape (N, 3) - orientations_target (Tensor): Orientation (encoded local yaw) target of each 3D box. shape (N, ) - offsets2d_target (Tensor): Offsets target of each projected 3D box. shape (N, 2) - dimensions_target (Tensor): Dimensions target of each 3D box. shape (N, 3) - downsample_ratio (int): The stride of feature map. """ img_h, img_w = img_shape[:2] batch_size, _, feat_h, feat_w = feat_shape width_ratio = float(feat_w / img_w) # 1/4 height_ratio = float(feat_h / img_h) # 1/4 assert width_ratio == height_ratio # Whether to filter the objects which are not in FOV. if self.filter_outside_objs: filter_outside_objs(gt_bboxes_list, gt_labels_list, gt_bboxes_3d_list, gt_labels_3d_list, centers2d_list, input_metas) # transform centers2d to base centers2d for regression and # heatmap generation. # centers2d = int(base_centers2d) + offsets2d base_centers2d_list, offsets2d_list, trunc_mask_list = \ handle_proj_objs(centers2d_list, gt_bboxes_list, input_metas) keypoints2d_list, keypoints_mask_list, keypoints_depth_mask_list = \ get_keypoints(gt_bboxes_3d_list, centers2d_list, input_metas) center_heatmap_target = gt_bboxes_list[-1].new_zeros( [batch_size, self.num_classes, feat_h, feat_w]) for batch_id in range(batch_size): # project gt_bboxes from input image to feat map gt_bboxes = gt_bboxes_list[batch_id] * width_ratio gt_labels = gt_labels_list[batch_id] # project base centers2d from input image to feat map gt_base_centers2d = base_centers2d_list[batch_id] * width_ratio trunc_masks = trunc_mask_list[batch_id] for j, base_center2d in enumerate(gt_base_centers2d): if trunc_masks[j]: # for outside objects, generate ellipse heatmap base_center2d_x_int, base_center2d_y_int = \ base_center2d.int() scale_box_w = min(base_center2d_x_int - gt_bboxes[j][0], gt_bboxes[j][2] - base_center2d_x_int) scale_box_h = min(base_center2d_y_int - gt_bboxes[j][1], gt_bboxes[j][3] - base_center2d_y_int) radius_x = scale_box_w * self.edge_heatmap_ratio radius_y = scale_box_h * self.edge_heatmap_ratio radius_x, radius_y = max(0, int(radius_x)), max( 0, int(radius_y)) assert min(radius_x, radius_y) == 0 ind = gt_labels[j] get_ellip_gaussian_2D( center_heatmap_target[batch_id, ind], [base_center2d_x_int, base_center2d_y_int], radius_x, radius_y) else: base_center2d_x_int, base_center2d_y_int = \ base_center2d.int() scale_box_h = (gt_bboxes[j][3] - gt_bboxes[j][1]) scale_box_w = (gt_bboxes[j][2] - gt_bboxes[j][0]) radius = gaussian_radius([scale_box_h, scale_box_w], min_overlap=0.7) radius = max(0, int(radius)) ind = gt_labels[j] gen_gaussian_target( center_heatmap_target[batch_id, ind], [base_center2d_x_int, base_center2d_y_int], radius) avg_factor = max(1, center_heatmap_target.eq(1).sum()) num_ctrs = [centers2d.shape[0] for centers2d in centers2d_list] max_objs = max(num_ctrs) batch_indices = [ centers2d_list[0].new_full((num_ctrs[i], ), i) for i in range(batch_size) ] batch_indices = torch.cat(batch_indices, dim=0) reg_mask = torch.zeros( (batch_size, max_objs), dtype=torch.bool).to(base_centers2d_list[0].device) gt_bboxes_3d = input_metas['box_type_3d'].cat(gt_bboxes_3d_list) gt_bboxes_3d = gt_bboxes_3d.to(base_centers2d_list[0].device) # encode original local yaw to multibin format orienations_target = self.bbox_coder.encode(gt_bboxes_3d) batch_base_centers2d = base_centers2d_list[0].new_zeros( (batch_size, max_objs, 2)) for i in range(batch_size): reg_mask[i, :num_ctrs[i]] = 1 batch_base_centers2d[i, :num_ctrs[i]] = base_centers2d_list[i] flatten_reg_mask = reg_mask.flatten() # transform base centers2d from input scale to output scale batch_base_centers2d = batch_base_centers2d.view(-1, 2) * width_ratio dimensions_target = gt_bboxes_3d.tensor[:, 3:6] labels_3d = torch.cat(gt_labels_3d_list) keypoints2d_target = torch.cat(keypoints2d_list) keypoints_mask = torch.cat(keypoints_mask_list) keypoints_depth_mask = torch.cat(keypoints_depth_mask_list) offsets2d_target = torch.cat(offsets2d_list) bboxes2d = torch.cat(gt_bboxes_list) # transform FCOS style bbox into [x1, y1, x2, y2] format. bboxes2d_target = torch.cat([bboxes2d[:, 0:2] * -1, bboxes2d[:, 2:]], dim=-1) depths = torch.cat(depths_list) target_labels = dict( base_centers2d_target=batch_base_centers2d.int(), labels3d=labels_3d, reg_mask=flatten_reg_mask, batch_indices=batch_indices, bboxes2d_target=bboxes2d_target, depth_target=depths, keypoints2d_target=keypoints2d_target, keypoints_mask=keypoints_mask, keypoints_depth_mask=keypoints_depth_mask, orienations_target=orienations_target, offsets2d_target=offsets2d_target, dimensions_target=dimensions_target, downsample_ratio=1 / width_ratio) return center_heatmap_target, avg_factor, target_labels def loss(self, cls_scores, bbox_preds, gt_bboxes, gt_labels, gt_bboxes_3d, gt_labels_3d, centers2d, depths, attr_labels, input_metas, gt_bboxes_ignore=None): """Compute loss of the head. Args: cls_scores (list[Tensor]): Box scores for each scale level. shape (num_gt, 4). bbox_preds (list[Tensor]): Box dims is a 4D-tensor, the channel number is bbox_code_size. shape (B, 7, H, W). gt_bboxes (list[Tensor]): Ground truth bboxes for each image. shape (num_gts, 4) in [tl_x, tl_y, br_x, br_y] format. gt_labels (list[Tensor]): Class indices corresponding to each box. shape (num_gts, ). gt_bboxes_3d (list[:obj:`CameraInstance3DBoxes`]): 3D boxes ground truth. it is the flipped gt_bboxes gt_labels_3d (list[Tensor]): Same as gt_labels. centers2d (list[Tensor]): 2D centers on the image. shape (num_gts, 2). depths (list[Tensor]): Depth ground truth. shape (num_gts, ). attr_labels (list[Tensor]): Attributes indices of each box. In kitti it's None. input_metas (list[dict]): Meta information of each image, e.g., image size, scaling factor, etc. gt_bboxes_ignore (None | list[Tensor]): Specify which bounding boxes can be ignored when computing the loss. Default: None. Returns: dict[str, Tensor]: A dictionary of loss components. """ assert len(cls_scores) == len(bbox_preds) == 1 assert attr_labels is None assert gt_bboxes_ignore is None center2d_heatmap = cls_scores[0] pred_reg = bbox_preds[0] center2d_heatmap_target, avg_factor, target_labels = \ self.get_targets(gt_bboxes, gt_labels, gt_bboxes_3d, gt_labels_3d, centers2d, depths, center2d_heatmap.shape, input_metas[0]['pad_shape'], input_metas) preds = self.get_predictions( pred_reg=pred_reg, labels3d=target_labels['labels3d'], centers2d=target_labels['base_centers2d_target'], reg_mask=target_labels['reg_mask'], batch_indices=target_labels['batch_indices'], input_metas=input_metas, downsample_ratio=target_labels['downsample_ratio']) # heatmap loss loss_cls = self.loss_cls( center2d_heatmap, center2d_heatmap_target, avg_factor=avg_factor) # bbox2d regression loss loss_bbox = self.loss_bbox(preds['bboxes2d'], target_labels['bboxes2d_target']) # keypoints loss, the keypoints in predictions and target are all # local coordinates. Check the mask dtype should be bool, not int # or float to ensure the indexing is bool index keypoints2d_mask = target_labels['keypoints2d_mask'] loss_keypoints = self.loss_keypoints( preds['keypoints2d'][keypoints2d_mask], target_labels['keypoints2d_target'][keypoints2d_mask]) # orientations loss loss_dir = self.loss_dir(preds['orientations'], target_labels['orientations_target']) # dimensions loss loss_dims = self.loss_dims(preds['dimensions'], target_labels['dimensions_target']) # offsets for center heatmap loss_offsets2d = self.loss_offsets2d(preds['offsets2d'], target_labels['offsets2d_target']) # directly regressed depth loss with direct depth uncertainty loss direct_depth_weights = torch.exp(-preds['direct_depth_uncertainty']) loss_weight_1 = self.loss_direct_depth.loss_weight loss_direct_depth = self.loss_direct_depth( preds['direct_depth'], target_labels['depth_target'], direct_depth_weights) loss_uncertainty_1 =\ preds['direct_depth_uncertainty'] * loss_weight_1 loss_direct_depth = loss_direct_depth + loss_uncertainty_1.mean() # keypoints decoded depth loss with keypoints depth uncertainty loss depth_mask = target_labels['keypoints_depth_mask'] depth_target = target_labels['depth_target'].unsqueeze(-1).repeat(1, 3) valid_keypoints_depth_uncertainty = preds[ 'keypoints_depth_uncertainty'][depth_mask] valid_keypoints_depth_weights = torch.exp( -valid_keypoints_depth_uncertainty) loss_keypoints_depth = self.loss_keypoint_depth( preds['keypoints_depth'][depth_mask], depth_target[depth_mask], valid_keypoints_depth_weights) loss_weight_2 = self.loss_keypoints_depth.loss_weight loss_uncertainty_2 =\ valid_keypoints_depth_uncertainty * loss_weight_2 loss_keypoints_depth = loss_keypoints_depth + loss_uncertainty_2.mean() # combined depth loss for optimiaze the uncertainty loss_combined_depth = self.loss_combined_depth( preds['combined_depth'], target_labels['depth_target']) loss_dict = dict( loss_cls=loss_cls, loss_bbox=loss_bbox, loss_keypoints=loss_keypoints, loss_dir=loss_dir, loss_dims=loss_dims, loss_offsets2d=loss_offsets2d, loss_direct_depth=loss_direct_depth, loss_keypoints_depth=loss_keypoints_depth, loss_combined_depth=loss_combined_depth) return loss_dict