Dynamic analysis of image sequences is an important task in object-ori
ented video applications. It often relies on the segmentation of each
image of the sequence into region entities of apparent homogeneous mot
ion. In this paper, we present an original motion segmentation algorit
hm based on 2D polynomial motion models, a multiresolution robust esti
mator to compute these motion models, and appropriate local observatio
ns supplying both motion relevant information and their reliability. M
otion segmentation is formulated as a contextual statistical labeling
problem exploiting multiscale Markov random field (MRF) models. One of
its main features is that it avoids time consuming alternate iteratio
ns between motion model estimation and spatial support identification.
An original detection step allows us to estimate and to update the nu
mber of required motion models, and thus to handle the appearance of n
ew objects. Numerous experiments performed with real indoor and outdoo
r image sequences demonstrate the efficiency of the method. (C) 1998 P
ublished by Elsevier Science B.V. All rights reserved.