Construction of fingerprint orientation field from minutia points

Construction of correct orientation field from minutia template is a critical problem in fingerprint recognition system. In this paper, a robust technique is proposed to construct fingerprint orientation field from minutia template based on interpolation. In order to perform interpolation, the Delaunay triangulation is used to create triangular triplet of minutia points. The bi-directional property of fingerprint ridge orientation is considered to achieve the minimum tolerance interval among the minutia points of a triplet. Barycentric coordinates of a point located inside a triangular region are considered as weight factor for the corresponding vertices. Experimentally, we observe that the weighted interpolation within smaller tolerance interval gives more accurate estimation. The performance of fingerprint recognition system can be improved by applying our proposed orientation estimation method.