Rule Based Composite Gradient Edge Operator
Ron Patton, Dragana P. Brzakovic · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1987
A gradient operator for detecting edges in imagery corrupted by noise is presented. Edge detectors that use masks to approximate derivative operations become imprecise in the presence of noise. Edge detectors which operate over small spatial scales (3 by 3) are ideal for edge localization and representing small detail; however, they respond equally well to high frequency noise and coarse textural information. Larger neighborhood operators (7 by 7) reduce the response to noise; however, edge localization and detail may be jeopardized. The Rule Based Composite Gradient Edge Operator (RBCGEO) interprets and integrates the responses of three operators each designed to extract edge information at a specific spatial resolution. The premise is that true edges have properties which will carry through several spatial scales while noise and other ambiguities will not. The RBCGEO uses a rule set to assign an edge magnitude, direction, and confidence of edge based on the composite response of the three operators. The algorithm and experimental results are presented.