Generating pencil drawing images of 3D objects

A simple technique is presented for generating pencil drawing images resembling hand-drawn sketches of 3D objects. We devised a method for extracting edge enhancement components by using division of an input image by its blurred one instead of conventional subtraction methods. Depth images are used for completion of edge enhancement components, which are impossible to extract from shading images. Edges are enhanced by removing one side of the edge enhancement shading. Thus, the obtained edge-enhanced shading images are transformed to stippling images using the point redistribution method presented by Secord et al. This stippling image is then anisotropically smoothed to produce a hatching image. We also applied this technique to moving images. One merit of our method is that it can produce movies with very low flicker without any specific overhead processing.