OpenCV图像处理之直方图比较方法详解

enum HistCompMethods {
    HISTCMP_CORREL        = 0,    //相关性比较
    HISTCMP_CHISQR        = 1,    //卡方比较
    HISTCMP_INTERSECT     = 2,    //十字交叉性
    HISTCMP_BHATTACHARYYA = 3,    //巴氏距离
    HISTCMP_HELLINGER     = HISTCMP_BHATTACHARYYA, 
    HISTCMP_CHISQR_ALT    = 4,    //替代卡方：通常用于纹理比较。
    HISTCMP_KL_DIV        = 5     //KL散度
};

#include"stdafx.h"
#include <opencv2/opencv.hpp>
#include <iostream>
#include <math.h>
 
using namespace std;
using namespace cv;
 
string convertToString(double d);
int main(int argc, char** argv) {
	Mat base, test1, test2;          //RGB图像
	Mat hsvbase, hsvtest1, hsvtest2; //HSV图像
	base = imread("F:/photo/zx.jpg");
	if (!base.data) {
		printf("could not load image...\n");
		return -1;
	}
	test1 = imread("F:/photo/a.jpg");
	test2 = imread("F:/photo/c.jpg");
	//转化为HSV图像
	cvtColor(base, hsvbase, COLOR_BGR2HSV);
	cvtColor(test1, hsvtest1, COLOR_BGR2HSV);
	cvtColor(test2, hsvtest2, COLOR_BGR2HSV);
 
	int h_bins = 50; int s_bins = 60;
	int histSize[] = { h_bins, s_bins };
	// hue varies from 0 to 179, saturation from 0 to 255     
	float h_ranges[] = { 0, 180 };
	float s_ranges[] = { 0, 256 };
	const float* ranges[] = { h_ranges, s_ranges };
	// Use the o-th and 1-st channels     
	int channels[] = { 0, 1 };
	MatND hist_base;
	MatND hist_test1;
	MatND hist_test2;
 
	calcHist(&hsvbase, 1, channels, Mat(), hist_base, 2, histSize, ranges, true, false);
	normalize(hist_base, hist_base, 0, 1, NORM_MINMAX, -1, Mat());
 
	calcHist(&hsvtest1, 1, channels, Mat(), hist_test1, 2, histSize, ranges, true, false);
	normalize(hist_test1, hist_test1, 0, 1, NORM_MINMAX, -1, Mat());
 
	calcHist(&hsvtest2, 1, channels, Mat(), hist_test2, 2, histSize, ranges, true, false);
	normalize(hist_test2, hist_test2, 0, 1, NORM_MINMAX, -1, Mat());
 
	double basebase = compareHist(hist_base, hist_base, 2);//zx
	double basetest1 = compareHist(hist_base, hist_test1,2);//zx and a
	double basetest2 = compareHist(hist_base, hist_test2, 2);//zx and c
	double tes1test2 = compareHist(hist_test1, hist_test2, 2);//a and c
	printf("test1 compare with test2 correlation value :%f", tes1test2);
 
	Mat test12;
	test2.copyTo(test12);
	putText(base, convertToString(basebase), Point(50, 50), FONT_HERSHEY_COMPLEX, 1, Scalar(0, 0, 255), 2, LINE_AA);  //zx
	putText(test1, convertToString(basetest1), Point(50, 50), FONT_HERSHEY_COMPLEX, 1, Scalar(0, 0, 255), 2, LINE_AA);//zx and a
	putText(test2, convertToString(basetest2), Point(50, 50), FONT_HERSHEY_COMPLEX, 1, Scalar(0, 0, 255), 2, LINE_AA);//zx and c
	putText(test12, convertToString(tes1test2), Point(50, 50), FONT_HERSHEY_COMPLEX, 1, Scalar(0, 0, 255), 2, LINE_AA);//a and c
 
	namedWindow("base", 0);
	resizeWindow("base", base.cols / 2, base.rows / 2);
	namedWindow("test1", 0);
	resizeWindow("test1", test1.cols / 2, test1.rows / 2);
	namedWindow("test2", 0);
	resizeWindow("test2", test2.cols / 2, test2.rows / 2);
 
	imshow("base", base);
	imshow("test1", test1);
	imshow("test2", test2);
	imshow("test12", test12);
 
	waitKey(0);
	return 0;
}
 
string convertToString(double d) {
	ostringstream os;
	if (os << d)
		return os.str();
	return "invalid conversion";
}