Skip to Main Content The skeleton of a digital figure can often
be regarded as a convenient alternative to the figure itself. It
is useful both to diminish drastically the amount of data to be
handled, and to simplify the computational procedures required
for description and classification purposes. Thinning a digital
figure down to its skeleton is a time-consuming process when
conventional sequential computers are employed. The procedure we
propose allows one to speed up the thinning transformation, and
to get a well-shaped skeleton. After cleaning of the input
picture has been performed, the pixels of the figure are labeled
according to their distance from the background, and a set,
whose pixels are symmetrically placed with respect to distinct
contour parts of the figure, is found. This set is then given a
linear structure by applying topology preserving removal
operations. Finally, a pruning step, regarding branches not
relevant in the framework of the problem domain, completes the
process. The resulting