Python OpenCV显示图像并保存图像

源码如下：

import numpy as np
import cv2
img = cv2.imread('lena.jpg',0)
cv2.imshow('image',img)
k = cv2.waitKey(0)
if k == 27:
    cv2.destroyAllWindows()
elif k == ord('s'):
    cv2.imwrite('lena.png',img)
    cv2.destroyAllWindows()