Verifying edges for visual inspection purposes

In this paper we develop a method for verifying edges for visual inspection purposes. This method characterizes and examines a candidate edge against a given condition which can be designed and modified according to the requi red specifications of an application. A criterion is established using the edge strength, edge length and the distributions of grey level values of th e pixels located in an edge neighbourhood. In consideration of computationa l speed and the accuracy of the locations of the edges, we first convolve t he image with a Gaussian impulse response with a single small smoothing sca le factor sigma to generate candidate edges. The candidate edges are verifi ed against the criterion and an edge is then retained or discarded on the b asis of its local characteristics. (C) 1999 Elsevier Science B.V. All right s reserved.