python实现图片变亮或者变暗的方法

import Image# open an image file (.jpg or.png) you have in the working folderim1 = Image.open("angelababy.jpg")# multiply each pixel by 0.9 (makes the image darker)# works best with .jpg and .png files, darker < 1.0 < lighter# (.bmp and .gif files give goofy results)# note that lambda is akin to a one-line functionim2 = im1.point(lambda p: p * 0.5)# brings up the modified image in a viewer, simply saves the image as# a bitmap to a temporary file and calls viewer associated with .bmp# make certain you have associated an image viewer with this file typeim2.show()# save modified image to working folder as Audi2.jpgim2.save("angelababy2.jpg")