Adaptation of Pair-Polar Structures to Compute a Secure and Alignment-Free Fingerprint Template

The unalterable nature of fingerprint biometrics leads to permanent identity loss of a user if an original fingerprint template is compromised. Moreover, it is evident in the literature that reconstructing a fingerprint image from an original fingerprint template is a feasible task. In order to protect the fingerprint template, we propose a noninvertible and alignment-free fingerprint template protection technique by exploiting the pair-polar minutiae structures. In the proposed technique, a secure fingerprint template is generated in the form of a set of binary vectors. These vectors are computed from the many-to-one mapping of the transformed pair-polar coordinates into a 3-D grid. Results of the proposed technique are analyzed in terms of revocability, unlinkability, security, and performance on six publicly available databases of Fingerprint Verification Competition 2002 and 2004. The overall analysis of the results clearly shows the effectiveness of the proposed technique as compared to the existing state-of-the-art techniques.