Gradient based edge detection methods are mainly focus on step edges. However local energy based edge detection methods and phase congruency based edge detection methods are effective both to step and peak edges. According to the characters of mammals visual cortex

this paper designs a group of quadrature filters by Hilbert transforms

by which the local energy and phase congruency are calculated. After noise analyzing and frequency distribution analyzing

edges are detected according to phase congruency value. As phase congruency based edge detection method is insensitive to variations in image illumination

and it makes looking for the maxima in local energy become unnecessary

we get good experimental result on the location and accuracy of edge detection.