-||-

modules/xphoto/src/dct_image_denoising.cpp

@@ -61,6 +61,8 @@ namespace cv
         Mat_<float> res( src.size(), 0.0f ),
                     num( src.size(), 0.0f );
 
+        double threshold = 2.0*log(psize)*sigma;
+
         for (int i = 0; i <= src.rows - psize; ++i)
             for (int j = 0; j <= src.cols - psize; ++j)
             {
@@ -69,7 +71,7 @@ namespace cv
                 dct(patch, patch);
                 float * ptr = (float *) patch.data;
                 for (int k = 0; k < psize*psize; ++k)
-                    if (fabs(ptr[k]) < 3.0f*sigma)
+                    if (fabs(ptr[k]) < threshold)
                         ptr[k] = 0.0f;
                 idct(patch, patch);
 

modules/xphoto/test/dct_image_denoising.cpp

@@ -14,13 +14,14 @@ namespace cvtest
         for (int i = 0; i < nTests; ++i)
         {
             cv::String srcName = dir + cv::format( "sources/%02d.png", i + 1);
-            cv::Mat src = cv::imread( srcName );
+            cv::Mat src = cv::imread( srcName, 1 );
 
             cv::String previousResultName = dir + cv::format( "results/%02d.png", i + 1 );
             cv::Mat previousResult = cv::imread( previousResultName, 1 );
 
-            cv::Mat currentResult;
+            cv::Mat currentResult, fastNlMeansResult;
             cv::dctDenoising(src, currentResult, sigma, psize);
+            cv::fastNlMeansDenoising(src, fastNlMeansResult);
 
             cv::Mat sqrError = ( currentResult - previousResult )
                 .mul( currentResult - previousResult );

modules/xphoto/test/test_precomp.hpp

@@ -13,6 +13,7 @@
 #include "opencv2/imgproc.hpp"
 #include "opencv2/imgproc/types_c.h"
 #include "opencv2/highgui.hpp"
+#include "opencv2/photo.hpp"
 #include "opencv2/xphoto.hpp"
 #include "opencv2/ts.hpp"
 #include <iostream>