ONLINE FINGERPRINT VERIFICATION

Fingerprint verification is one of the most reliable personal identifi cation methods. However, manual fingerprint verification is so tedious , time-consuming, and expensive that it is incapable of meeting today' s increasing performance requirements. An automatic fingerprint identi fication system (AFIS) is widely needed. It plays a very important rol e in forensic and civilian applications such as criminal identificatio n, access control, and ATM card verification. This paper describes the design and implementation of an on-line fingerprint verification syst em which operates in two stages: minutia extraction and minutia matchi ng. An improved version of the minutia extraction algorithm proposed b y Ratha et al,, which is much faster and more reliable, is implemented for extracting features from an input fingerprint image captured with an on-line inkless scanner. For minutia matching, an alignment-based elastic matching algorithm has been developed. This algorithm is capab le of finding the correspondences between minutiae in the input image and the stored template without resorting to exhaustive search and has the ability of adaptively compensating for the nonlinear deformations and inexact pose transformations between fingerprints. The system has been tested on two sets of fingerprint images captured with inkless s canners. The verification accuracy is found to be acceptable. Typicall y, a complete fingerprint verification procedure takes, on an average, about eight seconds on a SPARC 20 workstation. These experimental res ults show that our system meets the response time requirements of on-l ine verification with high accuracy.