.. ocv:function:: void circle( Mat& img, Point center, int radius, const Scalar& color, int thickness=1, int lineType=LINE_8, int shift=0 )
.. ocv:function:: void circle( InputOutputArray img, Point center, int radius, const Scalar& color, int thickness=1, int lineType=LINE_8, int shift=0 )
The methods are extended variants of ``GenericDescriptorMatch::match``. The parameters are similar, and the semantics is similar to ``DescriptorMatcher::knnMatch``. But this class does not require explicitly computed keypoint descriptors.