Miklos Olah, P.Masa, A. Lorincz, Dept of Chemical Physics, Hungarian Academy of Sciences, Budapest, Hungary.
In this paper a two-dimensional mixed-signal VLSI array is presented that can perform the morphological operation of skeletonization of binary images at a processing speed of up to 10K frames/second. The chip is a direct implementation of the grassfire method proposed by Blum. The system is a 2d array of identical processing elements (PEs) with integrated photodetectors allowing parallel optical input. The skeleton computation is performed in a fully parallel, asynchronous manner by local interactions between PEs., the transformed image is represented by analog values. The transformation is a VLSI analogue of time-integrated on-center-off-surround type nonlinear computation. The output of the transformation can be accessed serially with an on-chip raster-scan circuit generating multiscanning-compatible video signal. The system is currently being developed using a standard 0.7 
digital CMOS process. Simulation results and preliminary circuit specifications are presented.