python如何配置opencv

import cv2import numpy as npfrom matplotlib import pyplot as plt

img = cv2.imread('/home/aobo/Pictures/IMG_4137.JPG')color = ('b','g','r')# enumerate():python里的一个新函数

# 它的作用：同时遍历索引(i)和元素(col)for i,col in enumerate(color):

    histr = cv2.calcHist([img], [i], None, [256], [0, 256])

    plt.plot(histr, color = col)

    plt.xlim([0, 256])plt.show()