统计各个像素点的频率绘制直方图
计算各个像素点的累计概率
利用累计概率重新绘制图片

import cv2
import numpy as np
import matplotlib.pyplot as plt
img = cv2.imread('image0.jpg',1)
imgInfo = img.shape
height = imgInfo[0]
width = imgInfo[1]
gray = cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)
cv2.imshow('src',gray)
count = np.zeros(256,np.float)
for i in range(0,height):
    for j in range(0,width):
        pixel = gray[i,j]
        index = int(pixel)
        count[index] = count[index]+1
for i in range(0,255):
    count[i] = count[i]/(height*width)
#计算累计概率
sum1 = float(0)
for i in range(0,256):
    sum1 = sum1+count[i]
    count[i] = sum1
# 计算映射表
map1 = np.zeros(256,np.uint16)
for i in range(0,256):
    map1[i] = np.uint16(count[i]*255)
# 映射
for i in range(0,height):
    for j in range(0,width):
        pixel = gray[i,j]
        gray[i,j] = map1[pixel]
cv2.imshow('dst',gray)
cv2.waitKey(0)

原文链接:https://blog.csdn.net/m0_37712876/article/details/107451306