Trying to fix flann python wrapper issue

modules/features2d/src/matchers.cpp

@@ -1022,12 +1022,27 @@ FlannBasedMatcher::FlannBasedMatcher( const Ptr<flann::IndexParams>& _indexParam
 void FlannBasedMatcher::add( InputArrayOfArrays _descriptors )
 {
     DescriptorMatcher::add( _descriptors );
-    std::vector<UMat> descriptors;
-    _descriptors.getUMatVector(descriptors);
-
-    for( size_t i = 0; i < descriptors.size(); i++ )
+    if(_descriptors.isUMatVector() || _descriptors.isUMat())
+    {
+        std::vector<UMat> descriptors;
+        _descriptors.getUMatVector(descriptors);
+        for( size_t i = 0; i < descriptors.size(); i++ )
+        {
+            addedDescCount += descriptors[i].rows;
+        }
+    }
+    else if(_descriptors.isMatVector() || _descriptors.isMat())
+    {
+        std::vector<Mat> descriptors;
+        _descriptors.getMatVector(descriptors);
+        for( size_t i = 0; i < descriptors.size(); i++ )
+        {
+            addedDescCount += descriptors[i].rows;
+        }
+    }
+    else
     {
-        addedDescCount += descriptors[i].rows;
+        CV_Assert( _descriptors.isUMat() || _descriptors.isUMatVector() || _descriptors.isMat() || _descriptors.isMatVector());
     }
 }