--- /dev/null
+/**
+ * @file compareHist_Demo.cpp
+ * @brief Sample code to use the function compareHist
+ * @author OpenCV team
+ */
+
+#include "opencv2/highgui/highgui.hpp"
+#include "opencv2/imgproc/imgproc.hpp"
+#include <iostream>
+#include <stdio.h>
+
+using namespace std;
+using namespace cv;
+
+/**
+ * @function main
+ */
+int main( int argc, char** argv )
+{
+ Mat src_base, hsv_base;
+ Mat src_test1, hsv_test1;
+ Mat src_test2, hsv_test2;
+ Mat hsv_half_down;
+
+ /// Load three images with different environment settings
+ if( argc < 4 )
+ { printf("** Error. Usage: ./compareHist_Demo <image_settings0> <image_setting1> <image_settings2>\n");
+ return -1;
+ }
+
+ src_base = imread( argv[1], 1 );
+ src_test1 = imread( argv[2], 1 );
+ src_test2 = imread( argv[3], 1 );
+
+ /// Convert to HSV
+ cvtColor( src_base, hsv_base, CV_BGR2HSV );
+ cvtColor( src_test1, hsv_test1, CV_BGR2HSV );
+ cvtColor( src_test2, hsv_test2, CV_BGR2HSV );
+
+ hsv_half_down = hsv_base( Range( hsv_base.rows/2, hsv_base.rows - 1 ), Range( 0, hsv_base.cols - 1 ) );
+
+ /// Using 30 bins for hue and 32 for saturation
+ int h_bins = 50; int s_bins = 60;
+ int histSize[] = { h_bins, s_bins };
+
+ // hue varies from 0 to 256, saturation from 0 to 180
+ float h_ranges[] = { 0, 256 };
+ float s_ranges[] = { 0, 180 };
+
+ const float* ranges[] = { h_ranges, s_ranges };
+
+ // Use the o-th and 1-st channels
+ int channels[] = { 0, 1 };
+
+
+ /// Histograms
+ MatND hist_base;
+ MatND hist_half_down;
+ MatND hist_test1;
+ MatND hist_test2;
+
+ /// Calculate the histograms for the HSV images
+ calcHist( &hsv_base, 1, channels, Mat(), hist_base, 2, histSize, ranges, true, false );
+ normalize( hist_base, hist_base, 0, 1, NORM_MINMAX, -1, Mat() );
+
+ calcHist( &hsv_half_down, 1, channels, Mat(), hist_half_down, 2, histSize, ranges, true, false );
+ normalize( hist_half_down, hist_half_down, 0, 1, NORM_MINMAX, -1, Mat() );
+
+ calcHist( &hsv_test1, 1, channels, Mat(), hist_test1, 2, histSize, ranges, true, false );
+ normalize( hist_test1, hist_test1, 0, 1, NORM_MINMAX, -1, Mat() );
+
+ calcHist( &hsv_test2, 1, channels, Mat(), hist_test2, 2, histSize, ranges, true, false );
+ normalize( hist_test2, hist_test2, 0, 1, NORM_MINMAX, -1, Mat() );
+
+ /// Apply the histogram comparison methods
+ for( int i = 0; i < 4; i++ )
+ { int compare_method = i;
+ double base_base = compareHist( hist_base, hist_base, compare_method );
+ double base_half = compareHist( hist_base, hist_half_down, compare_method );
+ double base_test1 = compareHist( hist_base, hist_test1, compare_method );
+ double base_test2 = compareHist( hist_base, hist_test2, compare_method );
+
+ printf( " Method [%d] Perfect, Base-Half, Base-Test(1), Base-Test(2) : %f, %f, %f, %f \n", i, base_base, base_half , base_test1, base_test2 );
+ }
+
+ printf( "Done \n" );
+
+ return 0;
+}