A connectivity algorithm hardware implementation system wherein a subject pixel in a raster-scanned digitized image is declared a pixel of interest, in real time, by it being part of a potential target where every pixel on a closed pixel path enclosing the subject pixel differs in intensity from the intensity of the subject pixel by a predetermined intensity level, the system including a sequential delay line array producing a plurality of sequentially delayed digitized video signals representative of the spatial relationship of the pixels in the digitized image, these signals being coupled to a magnitude comparator array along with a delayed subject pixel contrast signal produced by a threshold circuit coupled to the subject pixel intensity causing the comparator array to produce a plurality of resultant signals representative of a comparison of the video signals with the subject pixel contrast signal, which resultant signals are coupled to a path checking circuit that simultaneously identifies all predetermined state closed paths around the subject pixel wherein every pixel on this closed path differs in intensity from an enclosed subject pixel by the predetermined intensity level. <IMAGE>
Real time connectivity algorithm system