A Computational Approach toEdgeDetection

image. We extend this simple detector using operators ofseveral widths tocopewithdifferent signal-to-noise ratios intheimage. We present ageneral method, called feature synthesis, forthefine-to-coarse integration ofinformation fromoperators atdifferent scales. Finally we showthatstepedgedetector performanceimproves considerably astheoperator point spread function is extended along theedge. Thisdetection scheme usesseveral elongated operators ateachpoint, andthedirectional operator outputs areintegrated withthegradient maximumdetector. Index Terms-Edge detection, feature extraction, imageprocessing, machine vision, multiscale imageanalysis.