Thinning is a frequently used method for extracting skeletons in discr
ete spaces. This paper presents an efficient parallel thinning algorit
hm that directly extracts medial lines from elongated 3D binary object
s (i.e., without creating medial surface). Our algorithm provides good
results, preserves topology and it is easy to implement. (C) 1998 Els
evier Science B.V. All rights reserved.