A Fingerprint Matching Algorithm Based on Radial Structure and a Structure-Rewarding Scoring Strategy

摘要

This paper proposes a new fingerprint matching algorithm for locally deformed fingerprints based on a geometric structure of minutiae, called the radial structure, which is a collection of lines from a minu-tia that connect its Voronoi neighbors. The proposed algorithm consists of local matching followed by global matching, in both of which a new robust scoring strategy is employed. The local matching compares individual radial structures of a query and a template, and the global matching, performed when the local matching fails, utilizes overall radial structures of a query. The algorithm has been tested using the FVC2002 DB1 fingerprint database on a Pentium-4 personal computer with 1.8 GHz clock and 256 Mbyte RAM. The test results show that the average matching time including preprocessing is 0.9 sec, and the equal error rate is 8.22%. It has been observed that the proposed algorithm has a smaller equal error rate by 7.18% than Mital and Teoh's. This is a substantial improvement in the equal error rate on the angle-distance based algorithm of Mital and Teoh. This improvement is attributed to the following features of the proposed algorithm: the radial structure is obtained from Voronoi neighboring minutiae, which results in more robustness to false minutiae; and the scoring strategy rewards similarity in the geometric structure rather than feature types as in Mital and Teoh's algorithm.