img = cv2.imread("1.jpg",cv2.IMREAD_UNCHANGED)
img = cv2.imread("1.jpg",cv2.IMREAD_ANYCOLOR | cv2.IMREAD_ANYDEPTH)
读取16bits的彩色通道图片.
img = cv2.imread("1.jpg",cv2.IMREAD_GRAYSCALE)
读取8bits的灰色通道图片
原文：https://www.cnblogs.com/sherman-mingjone/p/9060582.html