def get_ground_truth(self, anchors, targets):
gt_classes = []
gt_anchors_deltas = []
anchors = Boxes.cat(anchors)
for targets_per_image in targets:
match_quality_matrix = pairwise_iou(targets_per_image.gt_boxes,
anchors)
gt_matched_idxs, anchor_labels = self.matcher(match_quality_matrix)
has_gt = len(targets_per_image) > 0
if has_gt:
matched_gt_boxes = targets_per_image.gt_boxes[gt_matched_idxs]
gt_anchors_reg_deltas_i = self.box2box_transform.get_deltas(
anchors.tensor, matched_gt_boxes.tensor)
gt_classes_i = targets_per_image.gt_classes[gt_matched_idxs]
gt_classes_i[anchor_labels == 0] = self.num_classes
gt_classes_i[anchor_labels == -1] = -1
else:
gt_classes_i = torch.zeros_like(
gt_matched_idxs) + self.num_classes
gt_anchors_reg_deltas_i = torch.zeros_like(anchors.tensor)
gt_classes.append(gt_classes_i)
gt_anchors_deltas.append(gt_anchors_reg_deltas_i)
return torch.stack(gt_classes), torch.stack(gt_anchors_deltas)
def _match_and_label_boxes(self, proposals, stage, targets):
num_fg_samples, num_bg_samples = [], []
for proposals_per_image, targets_per_image in zip(proposals, targets):
match_quality_matrix = pairwise_iou(
targets_per_image.gt_boxes, proposals_per_image.proposal_boxes)
matched_idxs, proposal_labels = self.proposal_matchers[stage](
match_quality_matrix)
if len(targets_per_image) > 0:
gt_classes = targets_per_image.gt_classes[matched_idxs]
gt_classes[proposal_labels == 0] = self.num_classes
gt_boxes = targets_per_image.gt_boxes[matched_idxs]
else:
gt_classes = torch.zeros_like(matched_idxs) + self.num_classes
gt_boxes = Boxes(
targets_per_image.gt_boxes.tensor.new_zeros(
(len(proposals_per_image), 4)))
proposals_per_image.gt_classes = gt_classes
proposals_per_image.gt_boxes = gt_boxes
num_fg_samples.append((proposal_labels == 1).sum().item())
num_bg_samples.append(proposal_labels.numel() - num_fg_samples[-1])
storage = get_event_storage()
storage.put_scalar(
"stage{}/roi_head/num_fg_samples".format(stage),
sum(num_fg_samples) / len(num_fg_samples),
)
storage.put_scalar(
"stage{}/roi_head/num_bg_samples".format(stage),
sum(num_bg_samples) / len(num_bg_samples),
)
return proposals
def label_anchors(self, anchors, gt_instances):
anchors = Boxes.cat(anchors)
gt_labels = []
matched_gt_boxes = []
for gt_per_image in gt_instances:
match_quality_matrix = pairwise_iou(gt_per_image.gt_boxes, anchors)
matched_idxs, anchor_labels = self.anchor_matcher(
match_quality_matrix)
del match_quality_matrix
if len(gt_per_image) > 0:
matched_gt_boxes_i = gt_per_image.gt_boxes.tensor[matched_idxs]
gt_labels_i = gt_per_image.gt_classes[matched_idxs]
gt_labels_i[anchor_labels == 0] = self.num_classes
gt_labels_i[anchor_labels == -1] = -1
else:
matched_gt_boxes_i = torch.zeros_like(anchors.tensor)
gt_labels_i = torch.zeros_like(matched_idxs) + self.num_classes
gt_labels.append(gt_labels_i)
matched_gt_boxes.append(matched_gt_boxes_i)
return gt_labels, matched_gt_boxes
def label_and_sample_proposals(
self, proposals: List[Instances],
targets: List[Instances]) -> List[Instances]:
gt_boxes = [x.gt_boxes for x in targets]
if self.proposal_append_gt:
proposals = add_ground_truth_to_proposals(gt_boxes, proposals)
proposals_with_gt = []
num_fg_samples = []
num_bg_samples = []
for proposals_per_image, targets_per_image in zip(proposals, targets):
has_gt = len(targets_per_image) > 0
match_quality_matrix = pairwise_iou(
targets_per_image.gt_boxes, proposals_per_image.proposal_boxes)
matched_idxs, matched_labels = self.proposal_matcher(
match_quality_matrix)
sampled_idxs, gt_classes = self._sample_proposals(
matched_idxs, matched_labels, targets_per_image.gt_classes)
proposals_per_image = proposals_per_image[sampled_idxs]
proposals_per_image.gt_classes = gt_classes
if has_gt:
sampled_targets = matched_idxs[sampled_idxs]
for (trg_name,
trg_value) in targets_per_image.get_fields().items():
if trg_name.startswith(
"gt_") and not proposals_per_image.has(trg_name):
proposals_per_image.set(trg_name,
trg_value[sampled_targets])
else:
gt_boxes = Boxes(
targets_per_image.gt_boxes.tensor.new_zeros(
(len(sampled_idxs), 4)))
proposals_per_image.gt_boxes = gt_boxes
num_bg_samples.append(
(gt_classes == self.num_classes).sum().item())
num_fg_samples.append(gt_classes.numel() - num_bg_samples[-1])
proposals_with_gt.append(proposals_per_image)
storage = get_event_storage()
storage.put_scalar("roi_head/num_fg_samples", np.mean(num_fg_samples))
storage.put_scalar("roi_head/num_bg_samples", np.mean(num_bg_samples))
return proposals_with_gt
def _evaluate_box_proposals(dataset_predictions,
lvis_api,
thresholds=None,
area="all",
limit=None):
areas = {
"all": 0,
"small": 1,
"medium": 2,
"large": 3,
"96-128": 4,
"128-256": 5,
"256-512": 6,
"512-inf": 7,
}
area_ranges = [
[0**2, 1e5**2],
[0**2, 32**2],
[32**2, 96**2],
[96**2, 1e5**2],
[96**2, 128**2],
[128**2, 256**2],
[256**2, 512**2],
[512**2, 1e5**2],
]
assert area in areas, f"Unknown area range: {area}".format()
area_range = area_ranges[areas[area]]
gt_overlaps = []
num_pos = 0
for prediction_dict in dataset_predictions:
predictions = prediction_dict["proposals"]
inds = predictions.objectness_logits.sort(descending=True)[1]
predictions = predictions[inds]
ann_ids = lvis_api.get_ann_ids(img_ids=[prediction_dict["image_id"]])
anno = lvis_api.load_anns(ann_ids)
gt_boxes = [
BoxMode.convert(obj["bbox"], BoxMode.XYWH_ABS, BoxMode.XYXY_ABS)
for obj in anno
]
gt_boxes = torch.as_tensor(gt_boxes).reshape(-1, 4)
gt_boxes = Boxes(gt_boxes)
gt_areas = torch.as_tensor([obj["area"] for obj in anno])
if len(gt_boxes) == 0 or len(predictions) == 0:
continue
valid_gt_inds = (gt_areas >= area_range[0]) & (gt_areas <=
area_range[1])
gt_boxes = gt_boxes[valid_gt_inds]
num_pos += len(gt_boxes)
if len(gt_boxes) == 0:
continue
if limit is not None and len(predictions) > limit:
predictions = predictions[:limit]
overlaps = pairwise_iou(predictions.proposal_boxes, gt_boxes)
_gt_overlaps = torch.zeros(len(gt_boxes))
for j in range(min(len(predictions), len(gt_boxes))):
max_overlaps, argmax_overlaps = overlaps.max(dim=0)
gt_ovr, gt_ind = max_overlaps.max(dim=0)
assert gt_ovr >= 0
box_ind = argmax_overlaps[gt_ind]
_gt_overlaps[j] = overlaps[box_ind, gt_ind]
assert _gt_overlaps[j] == gt_ovr
overlaps[box_ind, :] = -1
overlaps[:, gt_ind] = -1
gt_overlaps.append(_gt_overlaps)
gt_overlaps = (torch.cat(gt_overlaps, dim=0) if len(gt_overlaps) else
torch.zeros(0, dtype=torch.float32))
gt_overlaps, _ = torch.sort(gt_overlaps)
if thresholds is None:
step = 0.05
thresholds = torch.arange(0.5, 0.95 + 1e-5, step, dtype=torch.float32)
recalls = torch.zeros_like(thresholds)
for i, t in enumerate(thresholds):
recalls[i] = (gt_overlaps >= t).float().sum() / float(num_pos)
ar = recalls.mean()
return {
"ar": ar,
"recalls": recalls,
"thresholds": thresholds,
"gt_overlaps": gt_overlaps,
"num_pos": num_pos,
}