code: public static <I extends ImageGray<I>, D extends ImageGray<D>>
  	DetectLineHoughFoot<I,D> houghFoot(@Nullable ConfigHoughFoot config ,
  									   Class<I> imageType ,
  									   Class<D> derivType ) {
  
  		if( config == null )
  			config = new ConfigHoughFoot();
  
  		ImageGradient<I,D> gradient = FactoryDerivative.sobel(imageType,derivType);
  
  		return new DetectLineHoughFoot<>(config.localMaxRadius, config.minCounts, config.minDistanceFromOrigin,
  				config.thresholdEdge, config.maxLines, gradient);
  	}
docs: Detects lines using the foot of norm parametrization, see {@link DetectLineHoughFoot}.  The polar
  parametrization is more common, but more difficult to tune.
  
  @see DetectLineHoughFoot
  
  @param config Configuration for line detector.  If null then default will be used.
  @param imageType Type of single band input image.
  @param derivType Image derivative type.
  @param <I> Input image type.
  @param <D> Image derivative type.
  @return Line detector.