2 * @file compareHist_Demo.cpp
3 * @brief Sample code to use the function compareHist
7 #include "opencv2/highgui/highgui.hpp"
8 #include "opencv2/imgproc/imgproc.hpp"
18 int main( int argc, char** argv )
20 Mat src_base, hsv_base;
21 Mat src_test1, hsv_test1;
22 Mat src_test2, hsv_test2;
25 /// Load three images with different environment settings
28 printf("** Error. Usage: ./compareHist_Demo <image_settings0> <image_setting1> <image_settings2>\n");
32 src_base = imread( argv[1], 1 );
33 src_test1 = imread( argv[2], 1 );
34 src_test2 = imread( argv[3], 1 );
37 cvtColor( src_base, hsv_base, COLOR_BGR2HSV );
38 cvtColor( src_test1, hsv_test1, COLOR_BGR2HSV );
39 cvtColor( src_test2, hsv_test2, COLOR_BGR2HSV );
41 hsv_half_down = hsv_base( Range( hsv_base.rows/2, hsv_base.rows - 1 ), Range( 0, hsv_base.cols - 1 ) );
43 /// Using 30 bins for hue and 32 for saturation
44 int h_bins = 50; int s_bins = 60;
45 int histSize[] = { h_bins, s_bins };
47 // hue varies from 0 to 256, saturation from 0 to 180
48 float s_ranges[] = { 0, 256 };
49 float h_ranges[] = { 0, 180 };
51 const float* ranges[] = { h_ranges, s_ranges };
53 // Use the o-th and 1-st channels
54 int channels[] = { 0, 1 };
63 /// Calculate the histograms for the HSV images
64 calcHist( &hsv_base, 1, channels, Mat(), hist_base, 2, histSize, ranges, true, false );
65 normalize( hist_base, hist_base, 0, 1, NORM_MINMAX, -1, Mat() );
67 calcHist( &hsv_half_down, 1, channels, Mat(), hist_half_down, 2, histSize, ranges, true, false );
68 normalize( hist_half_down, hist_half_down, 0, 1, NORM_MINMAX, -1, Mat() );
70 calcHist( &hsv_test1, 1, channels, Mat(), hist_test1, 2, histSize, ranges, true, false );
71 normalize( hist_test1, hist_test1, 0, 1, NORM_MINMAX, -1, Mat() );
73 calcHist( &hsv_test2, 1, channels, Mat(), hist_test2, 2, histSize, ranges, true, false );
74 normalize( hist_test2, hist_test2, 0, 1, NORM_MINMAX, -1, Mat() );
76 /// Apply the histogram comparison methods
77 for( int i = 0; i < 4; i++ )
79 int compare_method = i;
80 double base_base = compareHist( hist_base, hist_base, compare_method );
81 double base_half = compareHist( hist_base, hist_half_down, compare_method );
82 double base_test1 = compareHist( hist_base, hist_test1, compare_method );
83 double base_test2 = compareHist( hist_base, hist_test2, compare_method );
85 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 );