python BGR 转换为 RGB

将 numpy.ndarray 类型的 BGR 转为 RGB：

if __name__ == '__main__':
    image_path = '1.jpg'
    image = cv2.imread(image_path)	
    print('before image:', image.shape)	# (1520, 720, 3)
    out = image.transpose((2, 1, 0))[::-1]
    print('after image:', out.shape)	# (3, 720, 1520)