Methods and related apparatus for fingerprint indexing and searching

摘要

A method for indexing and searching a plurality of reference fingerprints to determine if a sample fingerprint matches one of the reference fingerprints includes the steps of: determining respective index values for the reference fingerprints and the sample fingerprint based upon characteristics of the fingerprints and with the index values being generally evenly distributed and continuous over a relatively large population of individuals; selecting a first subset of the reference fingerprints having index values in a first range relative to the index value of the sample fingerprint; and comparing the sample fingerprint to each fingerprint of the first subset of reference fingerprints to thereby determine if there is a match between the sample fingerprint and one of the reference fingerprints and without comparing the sample fingerprint to all of the reference fingerprints. The step of determining index values for the reference fingerprints and the sample fingerprint preferably comprises determining same based upon ridge flow curvature of the fingerprints. The step of selecting the first subset of reference fingerprints preferably comprises selecting same based upon an expected confidence value for locating the sample fingerprint in the first subset. Apparatus aspects of the invention are also disclosed.