private extern static void CvSURFDetectorDetectKeyPoints( ref MCvSURFParams detector, IntPtr image, IntPtr mask, IntPtr keypoints);
private extern static void CvSURFDetectorDetectFeature( ref MCvSURFParams detector, IntPtr image, IntPtr mask, IntPtr keypoints, IntPtr descriptors);
internal extern static IntPtr CvSURFDetectorCreate(ref MCvSURFParams detector, ref IntPtr featureDetector, ref IntPtr descriptorExtractor);