We develop a method to construct an implicit shape model that approxim
ates a solid object from its characteristic function. The method is ba
sed on multiresolution edge detection and reconstruction using dyadic
wavelets. It synthesizes edges at multiple resolutions such that the r
econstructed function preserves the shape boundary, and the gradient o
f the function gives the normal vector field at the boundary. Several
examples and applications of the procedure are given. One of the appli
cations consists of the procedure of obtaining a rough estimate of the
tubular neighborhood of a shape. We also apply this procedure to obta
in an approximate, but accurate, conversion from a parametric to an im
plicit surface. (C) 1995 Academic Press,Inc.