This parameter controls the size of areas the filter works with. Large values result in very thick black areas and much less detail in the resulting image. Small values result in more subtle pen strokes and more details preserved.

This parameter controls the amount of black color added to the image. Small values make the blend from color regions to blackened areas smoother and dark lines themselves thinner and less noticeable. Larger values make the lines thicker, darker and sharper. The maximum value makes the lines aliased. The best, most natural results are usually achieved with an intermediate value.