A MULTISCALE APPROACH TO IMAGE SEQUENCE-ANALYSIS

In optic flow based velocity estimation the image brightness constrain t equation is used, However, for measurements performed at a certain s cale, the brightness constraint equation does not apply. We therefore use a recently developed approach which reconciles optic flow and scal e space theory. It specifically incorporates the scale (aperture) of i mage measurements, leading to a scheme which is essentially different from existing approaches. To obtain a unique velocity field, the data- derived information has to be augmented with physical knowledge, By ke eping a strict separation between data-derived and external informatio n, we can locally adapt or modify the user-supplied information withou t affecting the image-derived information. The two free scale paramete rs in time and space can be used for attentive vision (selecting parti cular velocities or objects) and to improve the reliability of velocit y estimates. (C) 1997 Academic Press.