import warnings
import mmcv
import torch
from mmcv.image import tensor2imgs
from mmdet.core import bbox_mapping
from ..builder import DETECTORS, build_backbone, build_head, build_neck
from .base import BaseDetector
[docs]@DETECTORS.register_module()
class RPN(BaseDetector):
"""Implementation of Region Proposal Network."""
def __init__(self,
backbone,
neck,
rpn_head,
train_cfg,
test_cfg,
pretrained=None,
init_cfg=None):
super(RPN, self).__init__(init_cfg)
if pretrained:
warnings.warn('DeprecationWarning: pretrained is deprecated, '
'please use "init_cfg" instead')
backbone.pretrained = pretrained
self.backbone = build_backbone(backbone)
self.neck = build_neck(neck) if neck is not None else None
rpn_train_cfg = train_cfg.rpn if train_cfg is not None else None
rpn_head.update(train_cfg=rpn_train_cfg)
rpn_head.update(test_cfg=test_cfg.rpn)
self.rpn_head = build_head(rpn_head)
self.train_cfg = train_cfg
self.test_cfg = test_cfg
[docs] def forward_dummy(self, img):
"""Dummy forward function."""
x = self.extract_feat(img)
rpn_outs = self.rpn_head(x)
return rpn_outs
[docs] def forward_train(self,
img,
img_metas,
gt_bboxes=None,
gt_bboxes_ignore=None):
"""
Args:
img (Tensor): Input images of shape (N, C, H, W).
Typically these should be mean centered and std scaled.
img_metas (list[dict]): A List of image info dict where each dict
has: 'img_shape', 'scale_factor', 'flip', and may also contain
'filename', 'ori_shape', 'pad_shape', and 'img_norm_cfg'.
For details on the values of these keys see
:class:`mmdet.datasets.pipelines.Collect`.
gt_bboxes (list[Tensor]): Each item are the truth boxes for each
image in [tl_x, tl_y, br_x, br_y] format.
gt_bboxes_ignore (None | list[Tensor]): Specify which bounding
boxes can be ignored when computing the loss.
Returns:
dict[str, Tensor]: A dictionary of loss components.
"""
if (isinstance(self.train_cfg.rpn, dict)
and self.train_cfg.rpn.get('debug', False)):
self.rpn_head.debug_imgs = tensor2imgs(img)
x = self.extract_feat(img)
losses = self.rpn_head.forward_train(x, img_metas, gt_bboxes, None,
gt_bboxes_ignore)
return losses
[docs] def simple_test(self, img, img_metas, rescale=False):
"""Test function without test time augmentation.
Args:
imgs (list[torch.Tensor]): List of multiple images
img_metas (list[dict]): List of image information.
rescale (bool, optional): Whether to rescale the results.
Defaults to False.
Returns:
list[np.ndarray]: proposals
"""
x = self.extract_feat(img)
# get origin input shape to onnx dynamic input shape
if torch.onnx.is_in_onnx_export():
img_shape = torch._shape_as_tensor(img)[2:]
img_metas[0]['img_shape_for_onnx'] = img_shape
proposal_list = self.rpn_head.simple_test_rpn(x, img_metas)
if rescale:
for proposals, meta in zip(proposal_list, img_metas):
proposals[:, :4] /= proposals.new_tensor(meta['scale_factor'])
if torch.onnx.is_in_onnx_export():
return proposal_list
return [proposal.cpu().numpy() for proposal in proposal_list]
[docs] def aug_test(self, imgs, img_metas, rescale=False):
"""Test function with test time augmentation.
Args:
imgs (list[torch.Tensor]): List of multiple images
img_metas (list[dict]): List of image information.
rescale (bool, optional): Whether to rescale the results.
Defaults to False.
Returns:
list[np.ndarray]: proposals
"""
proposal_list = self.rpn_head.aug_test_rpn(
self.extract_feats(imgs), img_metas)
if not rescale:
for proposals, img_meta in zip(proposal_list, img_metas[0]):
img_shape = img_meta['img_shape']
scale_factor = img_meta['scale_factor']
flip = img_meta['flip']
flip_direction = img_meta['flip_direction']
proposals[:, :4] = bbox_mapping(proposals[:, :4], img_shape,
scale_factor, flip,
flip_direction)
return [proposal.cpu().numpy() for proposal in proposal_list]
[docs] def show_result(self, data, result, top_k=20, **kwargs):
"""Show RPN proposals on the image.
Args:
data (str or np.ndarray): Image filename or loaded image.
result (Tensor or tuple): The results to draw over `img`
bbox_result or (bbox_result, segm_result).
top_k (int): Plot the first k bboxes only
if set positive. Default: 20
Returns:
np.ndarray: The image with bboxes drawn on it.
"""
mmcv.imshow_bboxes(data, result, top_k=top_k)