import sys

import cv2
import numpy as np

加载彩色图像，日落照片为例

input_file = “sunset.jpg”
img = cv2.imread(input_file)

转化为灰度图像

img_gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)

cv2.imshow(‘Input grayscale image’, img_gray)

灰度图像直方图均衡

img_gray_histeq = cv2.equalizeHist(img_gray)

cv2.imshow(‘Histogram equalized - grayscale’, img_gray_histeq)

将彩色图转换到YUV色彩空间

img_yuv = cv2.cvtColor(img, cv2.COLOR_BGR2YUV)

均衡Y通道

img_yuv[:,:,0] = cv2.equalizeHist(img_yuv[:,:,0])

转回BGR图像

img_histeq = cv2.cvtColor(img_yuv, cv2.COLOR_YUV2BGR)

cv2.imshow(‘Input color image’, img)
cv2.imshow(‘Histogram equalized - color’, img_histeq)

cv2.waitKey()