A DIFFUSION MECHANISM FOR OBSTACLE DETECTION FROM SIZE-CHANGE INFORMATION

A mechanism for 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 i mage 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, derive d from a finite-difference approximation of the diffusion equation, es timates the immediacy measure from normal velocity and boundary inform ation provided by a motion measurement and segmentation stage. The alg orithm's performance on real image sequences is demonstrated.