code: public static <T extends ImageGray<T>, II extends ImageGray<II>>
  	DescribeRegionPoint<T,BrightFeature> surfStable(@Nullable ConfigSurfDescribe.Stability config, Class<T> imageType) {
  
  		Class<II> integralType = GIntegralImageOps.getIntegralType(imageType);
  
  		DescribePointSurf<II> alg = FactoryDescribePointAlgs.surfStability( config, integralType);
  
  		return new WrapDescribeSurf( alg , imageType );
  	}
docs: <p>
  Creates a SURF descriptor.  SURF descriptors are invariant to illumination, orientation, and scale.
  BoofCV provides two variants. The SURF variant created here is designed for stability.  Different
  descriptors are produced for gray-scale and color images.
  </p>
  
  @see DescribePointSurf
  
  @param config SURF configuration. Pass in null for default options.
  @param imageType Type of input image.
  @return SURF description extractor