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A NEW ALGORITHM TO COMPUTE DIRECTIONAL FIELDS AND SINGULAR POINTS FROM A FINGERPRINT

This paper proposes a new algorithm for computing directional fields and singular points from a fingerprint. Directional field (DF) is defined as the local orientation of the ridge valley structures and singular points (SPs) are the points in a fingerprint where the DF is discontinuous. DF and SPs can be used in fingerprint verification system. This paper shows the way of deriving DF from the gradients by performing some averaging operation on the gradients involving some pixels in some neighborhood. Various methods have been used to establish the DF from a fingerprint. These approaches do not provide as much accuracy as gradient based methods, mainly because of the limited number of possible orientations. This paper also shows SPs extraction method that uses segmentation algorithm. This segmentation algorithm will be capable of detecting low quality areas in a fingerprint. It is capable of high resolution SPs extraction and does not need to use heuristic post processing. We have evaluated the performance of the algorithm by experiments on a live scanned database. Experimental results show that this algorithm offers simple processing but presents more accurate results than traditional methods belong to.