A thinning algorithm for digital figures of characters

Abstract

A thinning scheme could be used as a useful method of pre-processing in image processing. Various algorithms have been proposed to produce the skeleton of a digital binary pattern. However, they have undesirable properties that tend to cause shrinking or vanishing of segments, the appearance of a beard, and warping where segments intersect. In this paper, we propose a parallel Hilditch algorithm to acquire a more stable output. In particular, we introduce two kinds of masks that are effective in the thinning of digital figures of characters. Then, we evaluate the performance of our scheme by investigating thinning for 432 kinds of commonly used character fonts. We conclude that the skeletons obtained from our method give better results than those of any other major thinning algorithms.