Dynamic threshold using polynomial surface regression with application to the binarisation of fingerprints

摘要

Dynamic thresholds are a popular and effective means of binarisation, used in image processing. We show that the method is a special case of a general setting in which input data from a background window are fitted with a polynomial surface after which the data from a smaller, embedded focus window are thresholded with respect to the fitted surface. The method has been implemented and used with good results in the context of fingerprint recognition.