def _std(inp): inp = mge.tensor(inp) return F.std(inp).numpy()
def get_ground_truth(self, anchors_list, batched_gt_boxes, batched_num_gts): labels_list = [] offsets_list = [] ctrness_list = [] all_level_anchors = F.concat(anchors_list, axis=0) for bid in range(batched_gt_boxes.shape[0]): gt_boxes = batched_gt_boxes[bid, :batched_num_gts[bid]] ious = [] candidate_idxs = [] base = 0 for stride, anchors_i in zip(self.cfg.stride, anchors_list): ious.append( layers.get_iou( gt_boxes[:, :4], F.concat([ anchors_i - stride * self.cfg.anchor_scale / 2, anchors_i + stride * self.cfg.anchor_scale / 2, ], axis=1))) gt_centers = (gt_boxes[:, :2] + gt_boxes[:, 2:4]) / 2 distances = F.sqrt( F.sum((F.expand_dims(gt_centers, axis=1) - anchors_i)**2, axis=2)) _, topk_idxs = F.topk(distances, self.cfg.anchor_topk) candidate_idxs.append(base + topk_idxs) base += anchors_i.shape[0] ious = F.concat(ious, axis=1) candidate_idxs = F.concat(candidate_idxs, axis=1) candidate_ious = F.gather(ious, 1, candidate_idxs) ious_thr = (F.mean(candidate_ious, axis=1, keepdims=True) + F.std(candidate_ious, axis=1, keepdims=True)) is_foreground = F.scatter( F.zeros(ious.shape), 1, candidate_idxs, F.ones(candidate_idxs.shape)).astype(bool) & (ious >= ious_thr) is_in_boxes = F.min(self.point_coder.encode( all_level_anchors, F.expand_dims(gt_boxes[:, :4], axis=1)), axis=2) > 0 ious[~is_foreground] = -1 ious[~is_in_boxes] = -1 match_indices = F.argmax(ious, axis=0) gt_boxes_matched = gt_boxes[match_indices] anchor_max_iou = F.indexing_one_hot(ious, match_indices, axis=0) labels = gt_boxes_matched[:, 4].astype(np.int32) labels[anchor_max_iou == -1] = 0 offsets = self.point_coder.encode(all_level_anchors, gt_boxes_matched[:, :4]) left_right = offsets[:, [0, 2]] top_bottom = offsets[:, [1, 3]] ctrness = F.sqrt( F.clip(F.min(left_right, axis=1) / F.max(left_right, axis=1), lower=0) * F.clip(F.min(top_bottom, axis=1) / F.max(top_bottom, axis=1), lower=0)) labels_list.append(labels) offsets_list.append(offsets) ctrness_list.append(ctrness) return ( F.stack(labels_list, axis=0).detach(), F.stack(offsets_list, axis=0).detach(), F.stack(ctrness_list, axis=0).detach(), )
def _anchor_double_target(gt_boxes, im_info, all_anchors): gt_boxes, im_info = gt_boxes.detach(), im_info.detach() all_anchors = all_anchors.detach() gt_boxes = gt_boxes[:im_info[5].astype(np.int32), :] dummy = -F.ones([1, gt_boxes.shape[1]]).to(gt_boxes.device) gt_boxes = F.concat([gt_boxes, dummy], axis=0) valid_mask = 1 - (gt_boxes[:, 4] < 0).astype(np.float32) anchor_centers = _compute_center(all_anchors) gtboxes_centers = _compute_center(gt_boxes) # gtboxes_centers = gtboxes_centers * valid_mask.unsqueeze(1) gtboxes_centers = gtboxes_centers * F.expand_dims(valid_mask, axis=1) N, K = all_anchors.shape[0], gt_boxes.shape[0] an_centers = F.expand_dims(anchor_centers, axis=1) gt_centers = F.expand_dims(gtboxes_centers, axis=0) # an_centers = anchor_centers.unsqueeze(1).repeat(1, K, 1) # gt_centers = gtboxes_centers.unsqueeze(0).repeat(N, 1, 1) distance = F.abs(an_centers - gt_centers) distance = F.sqrt(F.pow(distance, 2).sum(axis=2)) start = 0 end = 5 overlaps = box_overlap_opr(all_anchors[:, :4], gt_boxes[:, :4]) overlaps *= F.expand_dims(valid_mask, axis=0) default_num = 16 ious_list = [] for l in range(start, end): _, index = F.cond_take(all_anchors[:, 4] == l, all_anchors[:, 4]) level_dist = distance[index, :].transpose(1, 0) ious = overlaps[index, :].transpose(1, 0) sorted_index = F.argsort(level_dist, descending=False) n = min(sorted_index.shape[1], default_num) ious = F.gather(ious, 1, sorted_index[:, :n]).transpose(1, 0) ious_list.append(ious) ious = F.concat(ious_list, axis=0) mean_var = F.mean(ious, axis=0) std_var = F.std(ious, 0) iou_thresh_per_gt = mean_var + std_var iou_thresh_per_gt = F.maximum(iou_thresh_per_gt, 0.2) # limits the anchor centers in the gtboxes N, K = all_anchors.shape[0], gt_boxes.shape[0] anchor_points = an_centers pos_area = _compute_pos_area(gt_boxes, 0.3) # pos_area = pos_area.unsqueeze(0).repeat(N, 1, 1) pos_area = F.broadcast_to(F.expand_dims(pos_area, axis=0), (N, K, pos_area.shape[-1])) l = anchor_points[:, :, 0] - pos_area[:, :, 0] r = pos_area[:, :, 2] - anchor_points[:, :, 0] t = anchor_points[:, :, 1] - pos_area[:, :, 1] b = pos_area[:, :, 3] - anchor_points[:, :, 1] is_in_gt = F.stack([l, r, t, b], axis=2) is_in_gt = is_in_gt.min(axis=2) > 0.1 valid_mask = (overlaps >= F.expand_dims( iou_thresh_per_gt, axis=0)) * is_in_gt.astype(np.float32) ious = overlaps * valid_mask sorted_index = F.argsort(ious, 1) sorted_overlaps = F.gather(ious, 1, sorted_index) max_overlaps = sorted_overlaps[:, :2].flatten() argmax_overlaps = sorted_index[:, :2].flatten() n, c = all_anchors.shape device = all_anchors.device labels = -F.ones(2 * n).to(device) positive_mask = (max_overlaps >= 0.2).to(device).astype(np.float32) negative_mask = (max_overlaps < 0.2).to(device).astype(np.float32) labels = positive_mask + labels * (1 - positive_mask) * (1 - negative_mask) bbox_targets = gt_boxes[argmax_overlaps, :4] all_anchors = F.broadcast_to(F.expand_dims(all_anchors, axis=1), (n, 2, c)).reshape(-1, c) bbox_targets = bbox_transform_opr(all_anchors[:, :4], bbox_targets) labels_cat = gt_boxes[argmax_overlaps, 4] labels_cat = labels_cat * (1 - F.equal(labels, -1).astype( np.float32)) - F.equal(labels, -1).astype(np.float32) return labels, bbox_targets, labels_cat