|
|
|
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) |
|
|