The present work is intended for residual oxide scale detection and classification through the application of image processing
techniques. This is a defect that can remain in the surface of stainless steel coils after an incomplete pickling process in a
production line. From a previous detailed study over reflectance of residual oxide defect, we present a comparative study of
algorithms for image segmentation based on thresholding methods. In particular, two computational models based on multi-linear
regression and neural networks will be proposed. A system based on conventional area camera with a special lighting was
installed and fully integrated in an annealing and pickling line for model testing purposes. Finally, model approaches will be
compared and evaluated their performance..