关键词: 序列滤波器, 边缘检测, 表面缺陷, 中值滤波器, 总变差

Abstract: To extract defect features of steel strip surface，it is required to find the edges of defect correctly at first.With the deficiency of existing method in operation of the de-noising capacity，edge detail protection in complex background and uneven light，a new method is presented to detect edges of defect in steel strip surface.This method is based on using median filtering to compute the total variation with respect to the central pixel in a filter window.The result images are sent to Canny edge detector to find the edges which are taken as preprocessing images.As the final step，the binary morphological operators are used to remove isolated points and smooth the lines in order to get connected edges.The experimental result shows that the method in this paper is characterized by high noise inhibiting ability and can overcome the influence of noise and uneven light to detection result effectively.The better edges in complex background are obtained.

Key words: order filter, edge detection, surface defects, median filter, total variation