Analyzing looming motion components from their spatiotemporal spectral signature

This paper addresses the use of spatio-temporal transform methods applied to the analysis of dynamic image sequences and the characterization of image motion. The image motion including a divergent component (resulting from a looming camera component) is analyzed in the spatio-temporal Mellin transform (MT) domain, resulting in the separation of the spectrum into two parts: a structural term corresponding to the spatial MT of the static image, and a kinematic term depending on time-to-collision (a motion support). We examine potential applications of this property for the recovery of image motion from integral image brightness measurements and the computation of time-to-collision using spatio-temporal MT analysis