opencv —— compareHist 直方图比较

对比直方图：compareHist 函数

double compareHist(InputArray H1, InputArray H2, int method);

• H1，H2，是要进行比较的直方图。
• method，比较方法。有如下选择：

方法名	标识符	计算公式
相关  Correlation	HISTCMP_CORREL	其中   是直方图中bin的数目。
卡方 Chi-square	HISTCMP_CHISQR
相交  Intersection	HISTCMP_INTERSECT
巴氏距离  Bhattacharyya	HISTCMP_BHATTACHARYYA

 

代码示例：

#include<opencv.hpp>
#include<iostream>
#include<string>
using namespace std;
using namespace cv;
int main() {
    Mat src1 = imread("C:/Users/齐明洋/Desktop/证件照/6.jpg");
    Mat src2 = imread("C:/Users/齐明洋/Desktop/证件照/8.jpg");
    Mat src3 = imread("C:/Users/齐明洋/Desktop/证件照/10.jpg");
    imshow("src1", src1);
    imshow("src2", src2);
    imshow("src3", src3);

    //将图片转换成 HSV 类型
    //对 HS 两通道进行直方图统计
    cvtColor(src1, src1, COLOR_BGR2HSV);
    cvtColor(src2, src2, COLOR_BGR2HSV);
    cvtColor(src3, src3, COLOR_BGR2HSV);

    int channels[] = { 0,1 };
    int histsize[] = { 180,255 };
    float r1[] = { 0,180 };
    float r2[] = { 0,255 };
    const float *ranges[] = { r1,r2 };
    Mat hist1, hist2, hist3;
    calcHist(&src1, 3, channels, Mat(), hist1, 2, histsize, ranges, true);
    //https://www.cnblogs.com/bjxqmy/p/12292421.html
    normalize(hist1, hist1, 1, 0, NORM_L1);

    calcHist(&src2, 3, channels, Mat(), hist2, 2, histsize, ranges, true);
    normalize(hist2, hist2, 1, 0, NORM_L1);

    calcHist(&src3, 3, channels, Mat(), hist3, 2, histsize, ranges, true);
    normalize(hist3, hist3, 1, 0, NORM_L1);
    
    int method[] = { HISTCMP_CORREL,HISTCMP_CHISQR,HISTCMP_INTERSECT,HISTCMP_BHATTACHARYYA };
    string names[] = { "HISTCMP_CORREL","HISTCMP_CHISQR","HISTCMP_INTERSECT","HISTCMP_BHATTACHARYYA" };
    for (int i = 0; i < 4; i++) {
        cout << names[i] << ":" << endl;
        cout << "src1 and src1 :" << compareHist(hist1, hist1, method[i]) << endl;
        cout << "src1 and src2 :" << compareHist(hist1, hist2, method[i]) << endl;
        cout << "src1 and src3 :" << compareHist(hist1, hist3, method[i]) << endl;
        cout << endl;
    }
    waitKey(0);
}

效果演示：

 

 

借鉴博客：https://blog.csdn.net/qq_18343569/article/details/48028457