MOTION AND ILLUMINATION VARIATION ESTIMATION USING A HIERARCHY OF MODELS - APPLICATION TO IMAGE SEQUENCE CODING

In this paper, a new image sequence coding technique which exploits th e redundant information between two successive images of a sequence is presented. We propose to model the temporal variations of the images without the usual brightness constancy assumption, using motion and va riations of illumination parameters. This modeling approach leads to a hierarchy of temporal variation models. To achieve an efficient regio n-based adaptation, a criterion that combines the quality of reconstru ction and the parameter transmission cost is introduced. This hierarch y of temporal variation models is implemented using an efficient diffe rential estimation algorithm. High compression ratios with high qualit ies of reconstruction far motion- and illumination-compensated sequenc es are obtained. This algorithm is particularly efficient when complex natural motions and illumination variations occur in the image sequen ces. The proposed coding technique has been validated on real image se quences. Quantitative results in terms of peak signal-to-noise ratio a nd compression ratios are provided. (C) 1995 academic Press, Inc.