fixed #1507

samples/cpp/tutorial_code/Histograms_Matching/calcHist_Demo.cpp

@@ -25,57 +25,57 @@ int main( int argc, char** argv )
   if( !src.data )
     { return -1; }
 
-  /// Separate the image in 3 places ( R, G and B )
-  vector<Mat> rgb_planes;
-  split( src, rgb_planes ); 
+  /// Separate the image in 3 places ( B, G and R )
+  vector<Mat> bgr_planes;
+  split( src, bgr_planes );
 
-  /// Establish the number of bins 
-  int histSize = 255;
+  /// Establish the number of bins
+  int histSize = 256;
 
-  /// Set the ranges ( for R,G,B) )
-  float range[] = { 0, 255 } ; 
+  /// Set the ranges ( for B,G,R) )
+  float range[] = { 0, 256 } ;
   const float* histRange = { range };
 
   bool uniform = true; bool accumulate = false;
 
-  Mat r_hist, g_hist, b_hist;
+  Mat b_hist, g_hist, r_hist;
 
   /// Compute the histograms:
-  calcHist( &rgb_planes[0], 1, 0, Mat(), r_hist, 1, &histSize, &histRange, uniform, accumulate );
-  calcHist( &rgb_planes[1], 1, 0, Mat(), g_hist, 1, &histSize, &histRange, uniform, accumulate );
-  calcHist( &rgb_planes[2], 1, 0, Mat(), b_hist, 1, &histSize, &histRange, uniform, accumulate );
+  calcHist( &bgr_planes[0], 1, 0, Mat(), b_hist, 1, &histSize, &histRange, uniform, accumulate );
+  calcHist( &bgr_planes[1], 1, 0, Mat(), g_hist, 1, &histSize, &histRange, uniform, accumulate );
+  calcHist( &bgr_planes[2], 1, 0, Mat(), r_hist, 1, &histSize, &histRange, uniform, accumulate );
 
-  // Draw the histograms for R, G and B
-  int hist_w = 400; int hist_h = 400;
+  // Draw the histograms for B, G and R
+  int hist_w = 512; int hist_h = 400;
   int bin_w = cvRound( (double) hist_w/histSize );
 
-  Mat histImage( hist_w, hist_h, CV_8UC3, Scalar( 0,0,0) );
+  Mat histImage( hist_h, hist_w, CV_8UC3, Scalar( 0,0,0) );
 
   /// Normalize the result to [ 0, histImage.rows ]
-  normalize(r_hist, r_hist, 0, histImage.rows, NORM_MINMAX, -1, Mat() );
-  normalize(g_hist, g_hist, 0, histImage.rows, NORM_MINMAX, -1, Mat() );
   normalize(b_hist, b_hist, 0, histImage.rows, NORM_MINMAX, -1, Mat() );
+  normalize(g_hist, g_hist, 0, histImage.rows, NORM_MINMAX, -1, Mat() );
+  normalize(r_hist, r_hist, 0, histImage.rows, NORM_MINMAX, -1, Mat() );
 
-  /// Draw for each channel 
+  /// Draw for each channel
   for( int i = 1; i < histSize; i++ )
-    { 
-      line( histImage, Point( bin_w*(i-1), hist_h - cvRound(r_hist.at<float>(i-1)) ) , 
-		       Point( bin_w*(i), hist_h - cvRound(r_hist.at<float>(i)) ), 
-	               Scalar( 0, 0, 255), 2, 8, 0  ); 
-      line( histImage, Point( bin_w*(i-1), hist_h - cvRound(g_hist.at<float>(i-1)) ) , 
-		       Point( bin_w*(i), hist_h - cvRound(g_hist.at<float>(i)) ), 
-	               Scalar( 0, 255, 0), 2, 8, 0  ); 
-      line( histImage, Point( bin_w*(i-1), hist_h - cvRound(b_hist.at<float>(i-1)) ) , 
-		       Point( bin_w*(i), hist_h - cvRound(b_hist.at<float>(i)) ), 
-	               Scalar( 255, 0, 0), 2, 8, 0  );       
-    }
-
- /// Display 
+  {
+      line( histImage, Point( bin_w*(i-1), hist_h - cvRound(b_hist.at<float>(i-1)) ) ,
+                       Point( bin_w*(i), hist_h - cvRound(b_hist.at<float>(i)) ),
+                       Scalar( 255, 0, 0), 2, 8, 0  );
+      line( histImage, Point( bin_w*(i-1), hist_h - cvRound(g_hist.at<float>(i-1)) ) ,
+                       Point( bin_w*(i), hist_h - cvRound(g_hist.at<float>(i)) ),
+                       Scalar( 0, 255, 0), 2, 8, 0  );
+      line( histImage, Point( bin_w*(i-1), hist_h - cvRound(r_hist.at<float>(i-1)) ) ,
+                       Point( bin_w*(i), hist_h - cvRound(r_hist.at<float>(i)) ),
+                       Scalar( 0, 0, 255), 2, 8, 0  );
+  }
+
+  /// Display
   namedWindow("calcHist Demo", CV_WINDOW_AUTOSIZE );
   imshow("calcHist Demo", histImage );
 
   waitKey(0);
 
   return 0;
- 
+
 }