Check that image is gray in FREAK

modules/xfeatures2d/src/freak.cpp

@@ -334,8 +334,7 @@ void FREAK_Impl::compute( InputArray _image, std::vector<KeyPoint>& keypoints, O
 
     // Convert to gray if not already
     Mat grayImage = image;
-//    if( image.channels() > 1 )
-//        cvtColor( image, grayImage, COLOR_BGR2GRAY );
+    CV_Assert(grayImage.channels() == 1);
 
     // Use 32-bit integers if we won't overflow in the integral image
     if ((image.depth() == CV_8U || image.depth() == CV_8S) &&
@@ -682,10 +681,7 @@ imgType FREAK_Impl::meanIntensity( InputArray _image, InputArray _integral,
     ret_val += integral.at<iiType>(y_top,x_left);
     ret_val -= integral.at<iiType>(y_top,x_right);
     const int area = (x_right - x_left) * (y_bottom - y_top);
-    if(ret_val > 0)
-        ret_val = (ret_val + area/2) / area;
-    else
-        ret_val = (ret_val - area/2) / area;
+    ret_val = (ret_val + area/2) / area;
     //~ std::cout<<integral.step[1]<<std::endl;
     return static_cast<imgType>(ret_val);
 }

modules/xfeatures2d/test/test_features2d.cpp

@@ -298,8 +298,8 @@ public:
     typedef typename Distance::ResultType DistanceType;
 
     CV_DescriptorExtractorTest( const string _name, DistanceType _maxDist, const Ptr<DescriptorExtractor>& _dextractor,
-                                Distance d = Distance() ):
-            name(_name), maxDist(_maxDist), dextractor(_dextractor), distance(d) {}
+                                int imgMode = IMREAD_COLOR, Distance d = Distance()):
+            name(_name), maxDist(_maxDist), dextractor(_dextractor), imgLoadMode(imgMode), distance(d) {}
 protected:
     virtual void createDescriptorExtractor() {}
 
@@ -356,7 +356,10 @@ protected:
             ts->set_failed_test_info( cvtest::TS::FAIL_INVALID_TEST_DATA );
         }
 
-        image.create( 50, 50, CV_8UC3 );
+        if(imgLoadMode == IMREAD_GRAYSCALE)
+            image.create( 50, 50, CV_8UC1 );
+        else
+            image.create( 50, 50, CV_8UC3 );
         try
         {
             dextractor->compute( image, keypoints, descriptors );
@@ -389,7 +392,7 @@ protected:
         // Read the test image.
         string imgFilename =  string(ts->get_data_path()) + FEATURES2D_DIR + "/" + IMAGE_FILENAME;
 
-        Mat img = imread( imgFilename );
+        Mat img = imread( imgFilename, imgLoadMode );
         if( img.empty() )
         {
             ts->printf( cvtest::TS::LOG, "Image %s can not be read.\n", imgFilename.c_str() );
@@ -493,6 +496,7 @@ protected:
     string name;
     const DistanceType maxDist;
     Ptr<DescriptorExtractor> dextractor;
+    int imgLoadMode;
     Distance distance;
 
 private:
@@ -1021,7 +1025,7 @@ TEST( Features2d_DescriptorExtractor_FREAK, regression )
 {
     // TODO adjust the parameters below
     CV_DescriptorExtractorTest<Hamming> test( "descriptor-freak",  (CV_DescriptorExtractorTest<Hamming>::DistanceType)12.f,
-                                             FREAK::create() );
+                                             FREAK::create(), IMREAD_GRAYSCALE );
     test.safe_run();
 }
 

modules/xfeatures2d/test/test_rotation_and_scale_invariance.cpp

@@ -318,11 +318,12 @@ public:
     DescriptorRotationInvarianceTest(const Ptr<FeatureDetector>& _featureDetector,
                                      const Ptr<DescriptorExtractor>& _descriptorExtractor,
                                      int _normType,
-                                     float _minDescInliersRatio) :
+                                     float _minDescInliersRatio, int imgLoad = IMREAD_COLOR) :
         featureDetector(_featureDetector),
         descriptorExtractor(_descriptorExtractor),
         normType(_normType),
-        minDescInliersRatio(_minDescInliersRatio)
+        minDescInliersRatio(_minDescInliersRatio),
+        imgLoadMode(imgLoad)
     {
         CV_Assert(featureDetector);
         CV_Assert(descriptorExtractor);
@@ -335,7 +336,7 @@ protected:
         const string imageFilename = string(ts->get_data_path()) + IMAGE_TSUKUBA;
 
         // Read test data
-        Mat image0 = imread(imageFilename), image1, mask1;
+        Mat image0 = imread(imageFilename, imgLoadMode), image1, mask1;
         if(image0.empty())
         {
             ts->printf(cvtest::TS::LOG, "Image %s can not be read.\n", imageFilename.c_str());
@@ -398,6 +399,7 @@ protected:
     Ptr<DescriptorExtractor> descriptorExtractor;
     int normType;
     float minDescInliersRatio;
+    int imgLoadMode;
 };
 
 
@@ -696,6 +698,16 @@ TEST(Features2d_RotationInvariance_Descriptor_BRIEF_16, regression)
     test.safe_run();
 }
 
+TEST(Features2d_RotationInvariance_Descriptor_FREAK, regression)
+{
+    Ptr<Feature2D> f2d = FREAK::create();
+    DescriptorRotationInvarianceTest test(SURF::create(),
+                                          f2d,
+                                          f2d->defaultNorm(),
+                                          0.9f, IMREAD_GRAYSCALE);
+    test.safe_run();
+}
+
 /*
  * Detector's scale invariance check
  */