In this paper we present a nonlinear scale-space representation based on a
general class of morphological strong filters, the levelings, which include
the openings and closings by reconstruction. These filters are very useful
for image simplification and segmentation. From one scale to the next, det
ails vanish, but the contours of the remaining objects are preserved sharp
and perfectly localized. Both the lattice algebraic and the scale-space pro
perties of levelings are analyzed and illustrated. We also develop a nonlin
ear partial differential equation that models the generation of levelings a
s the limit of a controlled growth starting from an initial seed signal. Fi
nally, we outline the use of levelings in improving the Gaussian scale-spac
e by using the latter as an initial seed to generate multiscale levelings t
hat have a superior preservation of image edges. (C) 2000 Academic Press.