Metal surface control system based on successive contour estimation

A nondestructive control system is proposed. We consider an application of defect detection in metal workpieces. To solve this defect detection problem, we propose an image processing system including denoising, segmentation, and mapping. A contour preserving denoising method based on wavelet decomposition is adapted; various tools of contour based image segmentation are combined adequately, to segment successively high contrast and low contrast contours; generalized Hough transform is adapted to map processed and reference workpieces without defects. Comparative results are proposed which involve the proposed image processing system, and two region based segmentation methods.