• 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
    d(H_1,H_2) =  frac{sum_I (H_1(I) - ar{H_1}) (H_2(I) - ar{H_2})}{sqrt{sum_I(H_1(I) - ar{H_1})^2 sum_I(H_2(I) - ar{H_2})^2}}

    其中 ar{H_k} =  frac{1}{N} sum _J H_k(J)

    N 是直方图中bin的数目。

    卡方

    Chi-square

    HISTCMP_CHISQR
    d(H_1,H_2) =  sum _I  frac{left(H_1(I)-H_2(I)
ight)^2}{H_1(I)+H_2(I)}

    相交 

    Intersection

    HISTCMP_INTERSECT

    d(H_1,H_2) =  sum _I  min (H_1(I), H_2(I))

    巴氏距离 

    Bhattacharyya

    HISTCMP_BHATTACHARYYA
    d(H_1,H_2) =  sqrt{1 - frac{1}{sqrt{ar{H_1} ar{H_2} N^2}} sum_I sqrt{H_1(I) cdot H_2(I)}}

     

    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

     

  • 相关阅读:
    软件工程最后一次作业
    软件工程第四次作业
    软件工程第三次作业
    软件工程第一次作业
    软件工程第二次作业
    软件工程第一次作业
    2020年最后一次软工作业
    2020年第四次软工作业(第二次结对作业)
    2020年第三次软工作业(第一次结对作业)
    2020年第二次软工作业
  • 原文地址:https://www.cnblogs.com/bjxqmy/p/12379974.html
Copyright © 2020-2023  润新知