b3_data_iter.py 文件源码

def rel_crop(im, rel_cx, rel_cy, crop_size):

    map_size = im.shape[1]
    r = crop_size / 2
    abs_cx = rel_cx * map_size
    abs_cy = rel_cy * map_size
    na = np.floor([abs_cy-r, abs_cy+r, abs_cx-r, abs_cx+r]).astype(np.int32)
    a = np.clip(na, 0, map_size)
    px0 = a[2] - na[2]
    px1 = na[3] - a[3]
    py0 = a[0] - na[0]
    py1 = na[1] - a[1]
    crop = im[a[0]:a[1], a[2]:a[3]]
    crop = np.pad(crop, ((py0, py1), (px0, px1), (0, 0)),
                  mode='reflect')

    assert crop.shape == (crop_size, crop_size, im.shape[2])
    return crop