“…These methods failed to detect all the faults, especially the tiny ones [ 4 ]. This motivated researchers [ 5 , 6 , 7 , 8 ] to develop computer vision systems that are able to detect and classify defects in ceramic tiles [ 5 ], textile fabrics [ 9 , 10 ] and steel industries [ 7 , 8 , 9 , 11 , 12 ]. Structure-based methods extract image structure features such as texture, skeleton and edge, while other methods succeed to extract statistical features, such as mean, difference and variance [ 13 ], from the defect surface and then apply machine learning algorithms to train these features to recognize defected surfaces [ 14 , 15 ].…”