python+opencv 直方图比较

比较方法如下：

 

代码：

import cv2 as cv
import numpy as np
import matplotlib.pyplot as plt
import time

def create_rgb_hist(image):
    h,w,ch=image.shape
    rgbHist=np.zeros([16*16*16,1],np.float32)
    bsize=16
    for row in range(h):
        for col in range(w):
            b = image[row, col, 0]
            g = image[row, col, 1]
            r = image[row, col, 2]
            index = np.int(b/bsize)*16 * 16 + np.int(g/bsize)*16 + np.int(r/bsize) #下降成16个bin，由256*256*256降维4096
            print('index:',index)
            rgbHist[np.int(index),0]+=1
    return rgbHist

def hist_compare(image1,image2):
    hist1 = create_rgb_hist(image1)
    hist2 = create_rgb_hist(image2)
    match1 = cv.compareHist(hist1, hist2, cv.HISTCMP_BHATTACHARYYA)#越小越相似
    match2 = cv.compareHist(hist1, hist2, cv.HISTCMP_CORREL)#越大越相似
    match3 = cv.compareHist(hist1, hist2, cv.HISTCMP_CHISQR)  #越小越相似
    print('BHATTACHARYYA:',match1,'\n','CORREL:',match2,'\n','CHISQR:',match3)

image1=cv.imread('D:/pycharm/pycharmproject/test.jpg')
image2=cv.imread('D:/pycharm/pycharmproject/test.jpg')
cv.imshow('src',image1)
hist_compare(image1,image2)
cv.waitKey(0)
cv.destroyAllWindows()