Fingerprint singularity region image enhancement algorithm

Enhancement of fingerprint image near the singularity point is a big challenge in the fingerprint image enhancement. However, the ridge structure near the singular point of the fingerprint can be destroyed by the current Separable Gabor filter algorithm. And the performance in repairing the fingerprint ridge is bad by the current directional Fourier filter algorithm. These result in the bad performance in fingerprint image enhancement of the current Separable Gabor filter algorithm and Fourier filter algorithm. In order to improve the performance in the fingerprint image enhancement, this paper combines the advantages of the two algorithms and proposes the Fourier Separable Gabor algorithm (FS-Gabor). In the proposed FS-Gabor algorithm, the fingerprint image is preprocessed to obtain the fingerprint direction, frequency information and mask information firstly. Then in order to repaire the fingerprint ridge, the algorithm marks the area near the singular point as the aim filter area in the fingerprint image. Finally, different filtering methods are chosen to obtain the aim fingerprint image according to the position of the pixel. In addition, in order to expand the effective area of fingerprint image, an improved fingerprint image frequency estimation method is proposed in the FS-Gabor algorithm. According to the experiment results, it is indicated that the EER of fingerprint image filtered by the FS-Gabor algorithm is 26% lower than the directional Fourier filter algorithm and 49% lower than the Separable Gabor algorithm.