n06_pytorch_utils.py 文件源码

def randomShiftScale(img, u=0.25, limit=4):
    if random.random() < u:
        height, width, channel = img.shape
        assert (width == height)
        size0 = width
        size1 = width + 2 * limit
        img1 = cv2.copyMakeBorder(img, limit, limit, limit, limit, borderType=cv2.BORDER_REFLECT_101)
        size = round(random.uniform(size0, size1))

        dx = round(random.uniform(0, size1 - size))  # pixel
        dy = round(random.uniform(0, size1 - size))

        y1 = dy
        y2 = y1 + size
        x1 = dx
        x2 = x1 + size

        if size == size0:
            img = img1[y1:y2, x1:x2, :]
        else:
            img = cv2.resize(img1[y1:y2, x1:x2, :], (size0, size0), interpolation=cv2.INTER_LINEAR)

    return img