| |
| from typing import Optional, Tuple |
|
|
| import torch |
| from torch import Tensor |
|
|
| from mmdet.structures.bbox import BaseBoxes |
|
|
|
|
| def anchor_inside_flags(flat_anchors: Tensor, |
| valid_flags: Tensor, |
| img_shape: Tuple[int], |
| allowed_border: int = 0) -> Tensor: |
| """Check whether the anchors are inside the border. |
| |
| Args: |
| flat_anchors (torch.Tensor): Flatten anchors, shape (n, 4). |
| valid_flags (torch.Tensor): An existing valid flags of anchors. |
| img_shape (tuple(int)): Shape of current image. |
| allowed_border (int): The border to allow the valid anchor. |
| Defaults to 0. |
| |
| Returns: |
| torch.Tensor: Flags indicating whether the anchors are inside a \ |
| valid range. |
| """ |
| img_h, img_w = img_shape[:2] |
| if allowed_border >= 0: |
| if isinstance(flat_anchors, BaseBoxes): |
| inside_flags = valid_flags & \ |
| flat_anchors.is_inside([img_h, img_w], |
| all_inside=True, |
| allowed_border=allowed_border) |
| else: |
| inside_flags = valid_flags & \ |
| (flat_anchors[:, 0] >= -allowed_border) & \ |
| (flat_anchors[:, 1] >= -allowed_border) & \ |
| (flat_anchors[:, 2] < img_w + allowed_border) & \ |
| (flat_anchors[:, 3] < img_h + allowed_border) |
| else: |
| inside_flags = valid_flags |
| return inside_flags |
|
|
|
|
| def calc_region(bbox: Tensor, |
| ratio: float, |
| featmap_size: Optional[Tuple] = None) -> Tuple[int]: |
| """Calculate a proportional bbox region. |
| |
| The bbox center are fixed and the new h' and w' is h * ratio and w * ratio. |
| |
| Args: |
| bbox (Tensor): Bboxes to calculate regions, shape (n, 4). |
| ratio (float): Ratio of the output region. |
| featmap_size (tuple, Optional): Feature map size in (height, width) |
| order used for clipping the boundary. Defaults to None. |
| |
| Returns: |
| tuple: x1, y1, x2, y2 |
| """ |
| x1 = torch.round((1 - ratio) * bbox[0] + ratio * bbox[2]).long() |
| y1 = torch.round((1 - ratio) * bbox[1] + ratio * bbox[3]).long() |
| x2 = torch.round(ratio * bbox[0] + (1 - ratio) * bbox[2]).long() |
| y2 = torch.round(ratio * bbox[1] + (1 - ratio) * bbox[3]).long() |
| if featmap_size is not None: |
| x1 = x1.clamp(min=0, max=featmap_size[1]) |
| y1 = y1.clamp(min=0, max=featmap_size[0]) |
| x2 = x2.clamp(min=0, max=featmap_size[1]) |
| y2 = y2.clamp(min=0, max=featmap_size[0]) |
| return (x1, y1, x2, y2) |
|
|
