A diffusion mechanism for obstacle detection from size-change information

A mechanism fur the visual detection of obstacles is presented. A new immediacy measure, representing the imminence of collision between an object and a moving observer, is defined. A diffusion process on the image domain, whose initial condition is determined by the motion field normal to the object's boundary, is shown to converge asymptotically to the immediacy measure. A network of locally connected cells, derived from a finite-difference approximation of the diffusion equation, estimates the immediacy measure from normal velocity and boundary information provided by a motion measurement and segmentation stage. The algorithm's performance on real image sequences is demonstrated.<
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