Security-Enhanced Alignment-Free Fuzzy Vault-Based Fingerprint Cryptosystem Using Pair-Polar Minutiae Structures

 Alignment-free fingerprint cryptosystems perform matching using relative information between minutiae, e.g., local minutiae structures, is promising, because it can avoid the recognition errors and information leakage caused by template alignment/registration.

However, as most local minutiae structures only contain relative information of a few minutiae in a local region, they are less discriminative than the global minutiae pattern. Besides, the similarity measures for trivially/coarsely quantized features in the existing work cannot provide a robust way to deal with nonlinear distortions, a common form of intraclass variation. As a result, the recognition accuracy of current alignment-free fingerprint cryptosystems is unsatisfying.

In this project, we propose an alignment-free fuzzy vault-based fingerprint cryptosystem using highly discriminative pair-polar (P-P) minutiae structures. The fine quantization used in our system can largely retain information about a fingerprint template and enables the direct use of a traditional, well-established minutiae matcher.

In terms of template/key protection, the proposed system fuses cancelable biometrics and biocryptography. Transforming the P-P minutiae structures before encoding destroys the correlations between them, and can provide privacy-enhancing features, such as revocability and protection against cross-matching by setting distinct transformation seeds for different applications.

The comparison with other minutiae based fingerprint cryptosystems shows that the proposed system performs favorably on selected publicly available databases and has strong security.

This project proposes a security-enhanced alignment-free fuzzy vault-based fingerprint cryptosystem using pair-polar (P-P) minutiae structures.  The global minutiae matching algorithms is used to paired two fingerprint based on their minutiae. For security enhancement, each P-P minutiae structure is transformed before being encoded into the fuzzy vault. A two-level secure sketch a fuzzy vault and Shamir’s secret sharing scheme is used in the encoding procedure.