平均值灰度化

import cv2
import numpy as np
from matplotlib import pyplot as plt
img=cv2.imread('C:/Users/xpp/Desktop/Lena.png')#原始图像
cv2.imshow("original",img)
max_gray=np.zeros(img.shape[0:2],dtype='uint8')
ave_gray=np.zeros(img.shape[0:2],dtype='uint8')
weight_gray=np.zeros(img.shape[0:2],dtype='uint8')
for ii in range(img.shape[0]):
    for jj in range(img.shape[1]):
        r,g,b=img[ii,jj,:]
        ave_gray[ii,jj]=(r+g+b)/3#平均值灰度化
cv2.imshow("result",ave_gray)        
cv2.waitKey()
cv2.destroyAllWindows()