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# Copyright (c) OpenMMLab. All rights reserved.
from typing import List, Optional, Sequence, Tuple
import numpy as np
import torch
import torch.nn as nn
import torch.nn.functional as F
from mmcv.cnn import ConvModule
from mmengine.config import ConfigDict
from mmengine.structures import InstanceData
from torch import Tensor
from mmdet.models.layers import multiclass_nms
from mmdet.models.losses import accuracy
from mmdet.models.task_modules import SamplingResult
from mmdet.models.utils import multi_apply
from mmdet.registry import MODELS, TASK_UTILS
from mmdet.utils import ConfigType, InstanceList, OptConfigType, OptMultiConfig
from .bbox_head import BBoxHead
@MODELS.register_module()
class SABLHead(BBoxHead):
"""Side-Aware Boundary Localization (SABL) for RoI-Head.
Side-Aware features are extracted by conv layers
with an attention mechanism.
Boundary Localization with Bucketing and Bucketing Guided Rescoring
are implemented in BucketingBBoxCoder.
Please refer to https://arxiv.org/abs/1912.04260 for more details.
Args:
cls_in_channels (int): Input channels of cls RoI feature. \
Defaults to 256.
reg_in_channels (int): Input channels of reg RoI feature. \
Defaults to 256.
roi_feat_size (int): Size of RoI features. Defaults to 7.
reg_feat_up_ratio (int): Upsample ratio of reg features. \
Defaults to 2.
reg_pre_kernel (int): Kernel of 2D conv layers before \
attention pooling. Defaults to 3.
reg_post_kernel (int): Kernel of 1D conv layers after \
attention pooling. Defaults to 3.
reg_pre_num (int): Number of pre convs. Defaults to 2.
reg_post_num (int): Number of post convs. Defaults to 1.
num_classes (int): Number of classes in dataset. Defaults to 80.
cls_out_channels (int): Hidden channels in cls fcs. Defaults to 1024.
reg_offset_out_channels (int): Hidden and output channel \
of reg offset branch. Defaults to 256.
reg_cls_out_channels (int): Hidden and output channel \
of reg cls branch. Defaults to 256.
num_cls_fcs (int): Number of fcs for cls branch. Defaults to 1.
num_reg_fcs (int): Number of fcs for reg branch.. Defaults to 0.
reg_class_agnostic (bool): Class agnostic regression or not. \
Defaults to True.
norm_cfg (dict): Config of norm layers. Defaults to None.
bbox_coder (dict): Config of bbox coder. Defaults 'BucketingBBoxCoder'.
loss_cls (dict): Config of classification loss.
loss_bbox_cls (dict): Config of classification loss for bbox branch.
loss_bbox_reg (dict): Config of regression loss for bbox branch.
init_cfg (dict or list[dict], optional): Initialization config dict.
Defaults to None.
"""
def __init__(self,
num_classes: int,
cls_in_channels: int = 256,
reg_in_channels: int = 256,
roi_feat_size: int = 7,
reg_feat_up_ratio: int = 2,
reg_pre_kernel: int = 3,
reg_post_kernel: int = 3,
reg_pre_num: int = 2,
reg_post_num: int = 1,
cls_out_channels: int = 1024,
reg_offset_out_channels: int = 256,
reg_cls_out_channels: int = 256,
num_cls_fcs: int = 1,
num_reg_fcs: int = 0,
reg_class_agnostic: bool = True,
norm_cfg: OptConfigType = None,
bbox_coder: ConfigType = dict(
type='BucketingBBoxCoder',
num_buckets=14,
scale_factor=1.7),
loss_cls: ConfigType = dict(
type='CrossEntropyLoss',
use_sigmoid=False,
loss_weight=1.0),
loss_bbox_cls: ConfigType = dict(
type='CrossEntropyLoss',
use_sigmoid=True,
loss_weight=1.0),
loss_bbox_reg: ConfigType = dict(
type='SmoothL1Loss', beta=0.1, loss_weight=1.0),
init_cfg: OptMultiConfig = None) -> None:
super(BBoxHead, self).__init__(init_cfg=init_cfg)
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 = TASK_UTILS.build(bbox_coder)
self.loss_cls = MODELS.build(loss_cls)
self.loss_bbox_cls = MODELS.build(loss_bbox_cls)
self.loss_bbox_reg = MODELS.build(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)
if init_cfg is None:
self.init_cfg = [
dict(
type='Xavier',
layer='Linear',
distribution='uniform',
override=[
dict(type='Normal', name='reg_conv_att_x', std=0.01),
dict(type='Normal', name='reg_conv_att_y', std=0.01),
dict(type='Normal', name='fc_reg_cls', std=0.01),
dict(type='Normal', name='fc_cls', std=0.01),
dict(type='Normal', name='fc_reg_offset', std=0.001)
])
]
if self.reg_feat_up_ratio > 1:
self.init_cfg += [
dict(
type='Kaiming',
distribution='normal',
override=[
dict(name='upsample_x'),
dict(name='upsample_y')
])
]
def _add_fc_branch(self, num_branch_fcs: int, in_channels: int,
roi_feat_size: int,
fc_out_channels: int) -> nn.ModuleList:
"""build fc layers."""
in_channels = in_channels * roi_feat_size * roi_feat_size
branch_fcs = nn.ModuleList()
for i in range(num_branch_fcs):
fc_in_channels = (in_channels if i == 0 else fc_out_channels)
branch_fcs.append(nn.Linear(fc_in_channels, fc_out_channels))
return branch_fcs
def cls_forward(self, cls_x: Tensor) -> Tensor:
"""forward of classification fc layers."""
cls_x = cls_x.view(cls_x.size(0), -1)
for fc in self.cls_fcs:
cls_x = self.relu(fc(cls_x))
cls_score = self.fc_cls(cls_x)
return cls_score
def attention_pool(self, reg_x: Tensor) -> tuple:
"""Extract direction-specific features fx and fy with attention
methanism."""
reg_fx = reg_x
reg_fy = reg_x
reg_fx_att = self.reg_conv_att_x(reg_fx).sigmoid()
reg_fy_att = self.reg_conv_att_y(reg_fy).sigmoid()
reg_fx_att = reg_fx_att / reg_fx_att.sum(dim=2).unsqueeze(2)
reg_fy_att = reg_fy_att / reg_fy_att.sum(dim=3).unsqueeze(3)
reg_fx = (reg_fx * reg_fx_att).sum(dim=2)
reg_fy = (reg_fy * reg_fy_att).sum(dim=3)
return reg_fx, reg_fy
def side_aware_feature_extractor(self, reg_x: Tensor) -> tuple:
"""Refine and extract side-aware features without split them."""
for reg_pre_conv in self.reg_pre_convs:
reg_x = reg_pre_conv(reg_x)
reg_fx, reg_fy = self.attention_pool(reg_x)
if self.reg_post_num > 0:
reg_fx = reg_fx.unsqueeze(2)
reg_fy = reg_fy.unsqueeze(3)
for i in range(self.reg_post_num):
reg_fx = self.reg_post_conv_xs[i](reg_fx)
reg_fy = self.reg_post_conv_ys[i](reg_fy)
reg_fx = reg_fx.squeeze(2)
reg_fy = reg_fy.squeeze(3)
if self.reg_feat_up_ratio > 1:
reg_fx = self.relu(self.upsample_x(reg_fx))
reg_fy = self.relu(self.upsample_y(reg_fy))
reg_fx = torch.transpose(reg_fx, 1, 2)
reg_fy = torch.transpose(reg_fy, 1, 2)
return reg_fx.contiguous(), reg_fy.contiguous()
def reg_pred(self, x: Tensor, offset_fcs: nn.ModuleList,
cls_fcs: nn.ModuleList) -> tuple:
"""Predict bucketing estimation (cls_pred) and fine regression (offset
pred) with side-aware features."""
x_offset = x.view(-1, self.reg_in_channels)
x_cls = x.view(-1, self.reg_in_channels)
for fc in offset_fcs:
x_offset = self.relu(fc(x_offset))
for fc in cls_fcs:
x_cls = self.relu(fc(x_cls))
offset_pred = self.fc_reg_offset(x_offset)
cls_pred = self.fc_reg_cls(x_cls)
offset_pred = offset_pred.view(x.size(0), -1)
cls_pred = cls_pred.view(x.size(0), -1)
return offset_pred, cls_pred
def side_aware_split(self, feat: Tensor) -> Tensor:
"""Split side-aware features aligned with orders of bucketing
targets."""
l_end = int(np.ceil(self.up_reg_feat_size / 2))
r_start = int(np.floor(self.up_reg_feat_size / 2))
feat_fl = feat[:, :l_end]
feat_fr = feat[:, r_start:].flip(dims=(1, ))
feat_fl = feat_fl.contiguous()
feat_fr = feat_fr.contiguous()
feat = torch.cat([feat_fl, feat_fr], dim=-1)
return feat
def bbox_pred_split(self, bbox_pred: tuple,
num_proposals_per_img: Sequence[int]) -> tuple:
"""Split batch bbox prediction back to each image."""
bucket_cls_preds, bucket_offset_preds = bbox_pred
bucket_cls_preds = bucket_cls_preds.split(num_proposals_per_img, 0)
bucket_offset_preds = bucket_offset_preds.split(
num_proposals_per_img, 0)
bbox_pred = tuple(zip(bucket_cls_preds, bucket_offset_preds))
return bbox_pred
def reg_forward(self, reg_x: Tensor) -> tuple:
"""forward of regression branch."""
outs = self.side_aware_feature_extractor(reg_x)
edge_offset_preds = []
edge_cls_preds = []
reg_fx = outs[0]
reg_fy = outs[1]
offset_pred_x, cls_pred_x = self.reg_pred(reg_fx, self.reg_offset_fcs,
self.reg_cls_fcs)
offset_pred_y, cls_pred_y = self.reg_pred(reg_fy, self.reg_offset_fcs,
self.reg_cls_fcs)
offset_pred_x = self.side_aware_split(offset_pred_x)
offset_pred_y = self.side_aware_split(offset_pred_y)
cls_pred_x = self.side_aware_split(cls_pred_x)
cls_pred_y = self.side_aware_split(cls_pred_y)
edge_offset_preds = torch.cat([offset_pred_x, offset_pred_y], dim=-1)
edge_cls_preds = torch.cat([cls_pred_x, cls_pred_y], dim=-1)
return edge_cls_preds, edge_offset_preds
def forward(self, x: Tensor) -> tuple:
"""Forward features from the upstream network."""
bbox_pred = self.reg_forward(x)
cls_score = self.cls_forward(x)
return cls_score, bbox_pred
def get_targets(self,
sampling_results: List[SamplingResult],
rcnn_train_cfg: ConfigDict,
concat: bool = True) -> tuple:
"""Calculate the ground truth for all samples in a batch according to
the sampling_results."""
pos_proposals = [res.pos_bboxes for res in sampling_results]
neg_proposals = [res.neg_bboxes for res in sampling_results]
pos_gt_bboxes = [res.pos_gt_bboxes for res in sampling_results]
pos_gt_labels = [res.pos_gt_labels for res in sampling_results]
cls_reg_targets = self.bucket_target(
pos_proposals,
neg_proposals,
pos_gt_bboxes,
pos_gt_labels,
rcnn_train_cfg,
concat=concat)
(labels, label_weights, bucket_cls_targets, bucket_cls_weights,
bucket_offset_targets, bucket_offset_weights) = cls_reg_targets
return (labels, label_weights, (bucket_cls_targets,
bucket_offset_targets),
(bucket_cls_weights, bucket_offset_weights))
def bucket_target(self,
pos_proposals_list: list,
neg_proposals_list: list,
pos_gt_bboxes_list: list,
pos_gt_labels_list: list,
rcnn_train_cfg: ConfigDict,
concat: bool = True) -> tuple:
"""Compute bucketing estimation targets and fine regression targets for
a batch of images."""
(labels, label_weights, bucket_cls_targets, bucket_cls_weights,
bucket_offset_targets, bucket_offset_weights) = multi_apply(
self._bucket_target_single,
pos_proposals_list,
neg_proposals_list,
pos_gt_bboxes_list,
pos_gt_labels_list,
cfg=rcnn_train_cfg)
if concat:
labels = torch.cat(labels, 0)
label_weights = torch.cat(label_weights, 0)
bucket_cls_targets = torch.cat(bucket_cls_targets, 0)
bucket_cls_weights = torch.cat(bucket_cls_weights, 0)
bucket_offset_targets = torch.cat(bucket_offset_targets, 0)
bucket_offset_weights = torch.cat(bucket_offset_weights, 0)
return (labels, label_weights, bucket_cls_targets, bucket_cls_weights,
bucket_offset_targets, bucket_offset_weights)
def _bucket_target_single(self, pos_proposals: Tensor,
neg_proposals: Tensor, pos_gt_bboxes: Tensor,
pos_gt_labels: Tensor, cfg: ConfigDict) -> tuple:
"""Compute bucketing estimation targets and fine regression targets for
a single image.
Args:
pos_proposals (Tensor): positive proposals of a single image,
Shape (n_pos, 4)
neg_proposals (Tensor): negative proposals of a single image,
Shape (n_neg, 4).
pos_gt_bboxes (Tensor): gt bboxes assigned to positive proposals
of a single image, Shape (n_pos, 4).
pos_gt_labels (Tensor): gt labels assigned to positive proposals
of a single image, Shape (n_pos, ).
cfg (dict): Config of calculating targets
Returns:
tuple:
- labels (Tensor): Labels in a single image. Shape (n,).
- label_weights (Tensor): Label weights in a single image.
Shape (n,)
- bucket_cls_targets (Tensor): Bucket cls targets in
a single image. Shape (n, num_buckets*2).
- bucket_cls_weights (Tensor): Bucket cls weights in
a single image. Shape (n, num_buckets*2).
- bucket_offset_targets (Tensor): Bucket offset targets
in a single image. Shape (n, num_buckets*2).
- bucket_offset_targets (Tensor): Bucket offset weights
in a single image. Shape (n, num_buckets*2).
"""
num_pos = pos_proposals.size(0)
num_neg = neg_proposals.size(0)
num_samples = num_pos + num_neg
labels = pos_gt_bboxes.new_full((num_samples, ),
self.num_classes,
dtype=torch.long)
label_weights = pos_proposals.new_zeros(num_samples)
bucket_cls_targets = pos_proposals.new_zeros(num_samples,
4 * self.side_num)
bucket_cls_weights = pos_proposals.new_zeros(num_samples,
4 * self.side_num)
bucket_offset_targets = pos_proposals.new_zeros(
num_samples, 4 * self.side_num)
bucket_offset_weights = pos_proposals.new_zeros(
num_samples, 4 * self.side_num)
if num_pos > 0:
labels[:num_pos] = pos_gt_labels
label_weights[:num_pos] = 1.0
(pos_bucket_offset_targets, pos_bucket_offset_weights,
pos_bucket_cls_targets,
pos_bucket_cls_weights) = self.bbox_coder.encode(
pos_proposals, pos_gt_bboxes)
bucket_cls_targets[:num_pos, :] = pos_bucket_cls_targets
bucket_cls_weights[:num_pos, :] = pos_bucket_cls_weights
bucket_offset_targets[:num_pos, :] = pos_bucket_offset_targets
bucket_offset_weights[:num_pos, :] = pos_bucket_offset_weights
if num_neg > 0:
label_weights[-num_neg:] = 1.0
return (labels, label_weights, bucket_cls_targets, bucket_cls_weights,
bucket_offset_targets, bucket_offset_weights)
def loss(self,
cls_score: Tensor,
bbox_pred: Tuple[Tensor, Tensor],
rois: Tensor,
labels: Tensor,
label_weights: Tensor,
bbox_targets: Tuple[Tensor, Tensor],
bbox_weights: Tuple[Tensor, Tensor],
reduction_override: Optional[str] = None) -> dict:
"""Calculate the loss based on the network predictions and targets.
Args:
cls_score (Tensor): Classification prediction
results of all class, has shape
(batch_size * num_proposals_single_image, num_classes)
bbox_pred (Tensor): A tuple of regression prediction results
containing `bucket_cls_preds and` `bucket_offset_preds`.
rois (Tensor): RoIs with the shape
(batch_size * num_proposals_single_image, 5) where the first
column indicates batch id of each RoI.
labels (Tensor): Gt_labels for all proposals in a batch, has
shape (batch_size * num_proposals_single_image, ).
label_weights (Tensor): Labels_weights for all proposals in a
batch, has shape (batch_size * num_proposals_single_image, ).
bbox_targets (Tuple[Tensor, Tensor]): A tuple of regression target
containing `bucket_cls_targets` and `bucket_offset_targets`.
the last dimension 4 represents [tl_x, tl_y, br_x, br_y].
bbox_weights (Tuple[Tensor, Tensor]): A tuple of regression
weights containing `bucket_cls_weights` and
`bucket_offset_weights`.
reduction_override (str, optional): The reduction
method used to override the original reduction
method of the loss. Options are "none",
"mean" and "sum". Defaults to None,
Returns:
dict: A dictionary of loss.
"""
losses = dict()
if cls_score is not None:
avg_factor = max(torch.sum(label_weights > 0).float().item(), 1.)
losses['loss_cls'] = self.loss_cls(
cls_score,
labels,
label_weights,
avg_factor=avg_factor,
reduction_override=reduction_override)
losses['acc'] = accuracy(cls_score, labels)
if bbox_pred is not None:
bucket_cls_preds, bucket_offset_preds = bbox_pred
bucket_cls_targets, bucket_offset_targets = bbox_targets
bucket_cls_weights, bucket_offset_weights = bbox_weights
# edge cls
bucket_cls_preds = bucket_cls_preds.view(-1, self.side_num)
bucket_cls_targets = bucket_cls_targets.view(-1, self.side_num)
bucket_cls_weights = bucket_cls_weights.view(-1, self.side_num)
losses['loss_bbox_cls'] = self.loss_bbox_cls(
bucket_cls_preds,
bucket_cls_targets,
bucket_cls_weights,
avg_factor=bucket_cls_targets.size(0),
reduction_override=reduction_override)
losses['loss_bbox_reg'] = self.loss_bbox_reg(
bucket_offset_preds,
bucket_offset_targets,
bucket_offset_weights,
avg_factor=bucket_offset_targets.size(0),
reduction_override=reduction_override)
return losses
def _predict_by_feat_single(
self,
roi: Tensor,
cls_score: Tensor,
bbox_pred: Tuple[Tensor, Tensor],
img_meta: dict,
rescale: bool = False,
rcnn_test_cfg: Optional[ConfigDict] = None) -> InstanceData:
"""Transform a single image's features extracted from the head into
bbox results.
Args:
roi (Tensor): Boxes to be transformed. Has shape (num_boxes, 5).
last dimension 5 arrange as (batch_index, x1, y1, x2, y2).
cls_score (Tensor): Box scores, has shape
(num_boxes, num_classes + 1).
bbox_pred (Tuple[Tensor, Tensor]): Box cls preds and offset preds.
img_meta (dict): image information.
rescale (bool): If True, return boxes in original image space.
Defaults to False.
rcnn_test_cfg (obj:`ConfigDict`): `test_cfg` of Bbox Head.
Defaults to None
Returns:
:obj:`InstanceData`: Detection results of each image
Each item usually contains following keys.
- scores (Tensor): Classification scores, has a shape
(num_instance, )
- labels (Tensor): Labels of bboxes, has a shape
(num_instances, ).
- bboxes (Tensor): Has a shape (num_instances, 4),
the last dimension 4 arrange as (x1, y1, x2, y2).
"""
results = InstanceData()
if isinstance(cls_score, list):
cls_score = sum(cls_score) / float(len(cls_score))
scores = F.softmax(cls_score, dim=1) if cls_score is not None else None
img_shape = img_meta['img_shape']
if bbox_pred is not None:
bboxes, confidences = self.bbox_coder.decode(
roi[:, 1:], bbox_pred, img_shape)
else:
bboxes = roi[:, 1:].clone()
confidences = None
if img_shape is not None:
bboxes[:, [0, 2]].clamp_(min=0, max=img_shape[1] - 1)
bboxes[:, [1, 3]].clamp_(min=0, max=img_shape[0] - 1)
if rescale and bboxes.size(0) > 0:
assert img_meta.get('scale_factor') is not None
scale_factor = bboxes.new_tensor(img_meta['scale_factor']).repeat(
(1, 2))
bboxes = (bboxes.view(bboxes.size(0), -1, 4) / scale_factor).view(
bboxes.size()[0], -1)
if rcnn_test_cfg is None:
results.bboxes = bboxes
results.scores = scores
else:
det_bboxes, det_labels = multiclass_nms(
bboxes,
scores,
rcnn_test_cfg.score_thr,
rcnn_test_cfg.nms,
rcnn_test_cfg.max_per_img,
score_factors=confidences)
results.bboxes = det_bboxes[:, :4]
results.scores = det_bboxes[:, -1]
results.labels = det_labels
return results
def refine_bboxes(self, sampling_results: List[SamplingResult],
bbox_results: dict,
batch_img_metas: List[dict]) -> InstanceList:
"""Refine bboxes during training.
Args:
sampling_results (List[:obj:`SamplingResult`]): Sampling results.
bbox_results (dict): Usually is a dictionary with keys:
- `cls_score` (Tensor): Classification scores.
- `bbox_pred` (Tensor): Box energies / deltas.
- `rois` (Tensor): RoIs with the shape (n, 5) where the first
column indicates batch id of each RoI.
- `bbox_targets` (tuple): Ground truth for proposals in a
single image. Containing the following list of Tensors:
(labels, label_weights, bbox_targets, bbox_weights)
batch_img_metas (List[dict]): List of image information.
Returns:
list[:obj:`InstanceData`]: Refined bboxes of each image.
"""
pos_is_gts = [res.pos_is_gt for res in sampling_results]
# bbox_targets is a tuple
labels = bbox_results['bbox_targets'][0]
cls_scores = bbox_results['cls_score']
rois = bbox_results['rois']
bbox_preds = bbox_results['bbox_pred']
if cls_scores.numel() == 0:
return None
labels = torch.where(labels == self.num_classes,
cls_scores[:, :-1].argmax(1), labels)
img_ids = rois[:, 0].long().unique(sorted=True)
assert img_ids.numel() <= len(batch_img_metas)
results_list = []
for i in range(len(batch_img_metas)):
inds = torch.nonzero(
rois[:, 0] == i, as_tuple=False).squeeze(dim=1)
num_rois = inds.numel()
bboxes_ = rois[inds, 1:]
label_ = labels[inds]
edge_cls_preds, edge_offset_preds = bbox_preds
edge_cls_preds_ = edge_cls_preds[inds]
edge_offset_preds_ = edge_offset_preds[inds]
bbox_pred_ = (edge_cls_preds_, edge_offset_preds_)
img_meta_ = batch_img_metas[i]
pos_is_gts_ = pos_is_gts[i]
bboxes = self.regress_by_class(bboxes_, label_, bbox_pred_,
img_meta_)
# filter gt bboxes
pos_keep = 1 - pos_is_gts_
keep_inds = pos_is_gts_.new_ones(num_rois)
keep_inds[:len(pos_is_gts_)] = pos_keep
results = InstanceData(bboxes=bboxes[keep_inds.type(torch.bool)])
results_list.append(results)
return results_list
def regress_by_class(self, rois: Tensor, label: Tensor, bbox_pred: tuple,
img_meta: dict) -> Tensor:
"""Regress the bbox for the predicted class. Used in Cascade R-CNN.
Args:
rois (Tensor): shape (n, 4) or (n, 5)
label (Tensor): shape (n, )
bbox_pred (Tuple[Tensor]): shape [(n, num_buckets *2), \
(n, num_buckets *2)]
img_meta (dict): Image meta info.
Returns:
Tensor: Regressed bboxes, the same shape as input rois.
"""
assert rois.size(1) == 4 or rois.size(1) == 5
if rois.size(1) == 4:
new_rois, _ = self.bbox_coder.decode(rois, bbox_pred,
img_meta['img_shape'])
else:
bboxes, _ = self.bbox_coder.decode(rois[:, 1:], bbox_pred,
img_meta['img_shape'])
new_rois = torch.cat((rois[:, [0]], bboxes), dim=1)
return new_rois