We propose an improved thinning algorithm. Basically, the algorithm us
es a 3 x 3 window to accommodate an eight-neighbor skeleton in each th
inning iteration. This algorithm overcomes many thinning problems, suc
h as Y-shaped distortions, spiky skeletons and skeleton shortening, an
d thus preserves precise features of digital character patterns. By us
ing this thinning algorithm, better structural features of a character
pattern can be provided to an optical character recognition system, s
uch that accurate recognition results can be achieved.