when read the code of YOLOv4, I saw the code as below. whats the "..." operator means in a python list. It seams that "..." is not used any more in python3. thanks for viewing!
def bbox_iou(bboxes1, bboxes2):
"""
@param bboxes1: (a, b, ..., 4)
@param bboxes2: (A, B, ..., 4)
x:X is 1:n or n:n or n:1
@return (max(a,A), max(b,B), ...)
ex) (4,):(3,4) -> (3,)
(2,1,4):(2,3,4) -> (2,3)
"""
bboxes1_area = bboxes1[..., 2] * bboxes1[..., 3]
bboxes2_area = bboxes2[..., 2] * bboxes2[..., 3]
bboxes1_coor = tf.concat(
[
bboxes1[..., :2] - bboxes1[..., 2:] * 0.5,
bboxes1[..., :2] + bboxes1[..., 2:] * 0.5,
],
axis=-1,
)
bboxes2_coor = tf.concat(
[
bboxes2[..., :2] - bboxes2[..., 2:] * 0.5,
bboxes2[..., :2] + bboxes2[..., 2:] * 0.5,
],
axis=-1,
)
left_up = tf.maximum(bboxes1_coor[..., :2], bboxes2_coor[..., :2])
right_down = tf.minimum(bboxes1_coor[..., 2:], bboxes2_coor[..., 2:])
inter_section = tf.maximum(right_down - left_up, 0.0)
inter_area = inter_section[..., 0] * inter_section[..., 1]
union_area = bboxes1_area + bboxes2_area - inter_area
iou = tf.math.divide_no_nan(inter_area, union_area)
return iou
