docs: public static <T extends ImageGray<T>>
  	SparseScaleGradient<T,?> createGradient( boolean useHaar , Class<T> imageType )
  	{
  		if( useHaar )
  			return FactorySparseIntegralFilters.haar(imageType);
  		else
  			return FactorySparseIntegralFilters.gradient(imageType);
  	}