Edge Detectors Based on Nonlinear Filters

A class of edge detectors is proposed which is obtained from the difference of the outputs of two nonlinear filters. The nonlinear filters used are based on nonlinear means (which contain homomorphic filters) or order statistic (which contain median filters). The performance of these edge detectors in the presence of noise is evaluated and is compared to the performance of well established edge detectors. Their computational requirements are described and some examples are presented.