On-line defect detection algorithms for surface inspection of hot rolled strips

As there are a lot of scales, water drops and color differences on the surface of hot rolled strips, traditional algorithms of defect detection is not applicable for on-line surface inspection of hot rolled strips. New algorithms are developed, including three steps, which are image segmentation, four types of detection, and defect classification. Image segmentation is in real-time thread, while four types of detection are in just-in-time thread and defect classification is in idle-time thread. Three steps are implemented in the parallel mode for on-line inspection. The algorithms are applied to a newly developed surface inspection system of hot rolled strips, and time costs of the algorithms are bellow needs of on-line inspection.