docs: public static <T extends ImageGray<T>>
  	OrientationImage<T> convertImage( RegionOrientation algorithm , Class<T> imageType ) {
  		if( algorithm instanceof OrientationGradient ) {
  			Class derivType = ((OrientationGradient) algorithm).getImageType();
  			ImageGradient gradient = FactoryDerivative.sobel(imageType,derivType);
  			return new OrientationGradientToImage((OrientationGradient)algorithm,gradient,imageType,derivType);
  		} else if( algorithm instanceof OrientationIntegral ) {
  			Class integralType = GIntegralImageOps.getIntegralType(imageType);
  			return new OrientationIntegralToImage((OrientationIntegral)algorithm,imageType,integralType);
  		} else {
  			throw new IllegalArgumentException("Unknown orientation algorithm type");
  		}
  	}