A novel edge detector based on nonlinear local operations

A new type of edge detector is presented that uses spatial filtering of the locally thresholded image. The process is realized in two main stages. In the first one an appropriate threshold is used and the multilevel image is transformed to binary one. The second stage verifies the existence of an edge point by correlating the binary valued image points with certain binary valued spatial patterns. False edge points generated by noise are removed by means of another complementary filtering path based on the edge step size