Extension and generalization of recursive digital filters for edge detection

In this paper we give a method to detect edges in digital images based on the second order recursive implementation of a filter. These filters are directly designed in the discrete domain. We report the result of a set of experimental trials carried out to detect edges in digital signals. This design of filter for edge detection has the advantage of the simplicity. The lack of criteria, as those defined by J. Canny (1986) for analog filters, allows just to compare the digital filters with a qualitative method