Patent Document ID: 20020168093
Application ID: 09841144
Patent Status: 0

Claim One:
1. A prescreen method for prescreening the matching of an unidentified search fingerprint with a set of file fingerprints in a reference file comprising: a. identifying a set of characterizing minutia for each unidentified search fingerprint and file fingerprint to be compared, which includes at least a positional location and a directional component for each minutia; b. for each minutia, while considering that minutia to be a central minutia, identifying a set of minutia neighbors for that central minutia based upon the directional component of the central minutia by dividing the space about that central minutia into a plurality of quadrants referenced to the directional component of the central minutia, wherein the closest minutia in each of the quadrants is determined to be the minutia neighbor in that quadrant of the central minutia; c. comparing the directional components of each different pair of minutia in the unidentified fingerprint and the file fingerprint to ensure that they are within a given angular tolerance, which is selected to allow for a reasonable variation in rotational alignments between the different fingerprints, but does not allow a pair of minutia from completely different ridge flows to be compared; d. for the different passed pairs of minutia which are within the given angular tolerance, generating a matching score for each passed pair of minutia by performing a virtual alignment of the pair of minutia in location and direction, and then by comparing the distances and relative orientations between each of the pairs of minutia neighbors in each of the plurality of quadrants, which represents how well each different pair of minutia match each other; e. determining file fingerprints to be passed onto a more rigorous and complete matching with the unidentified fingerprint in an automated fingerprint identification system on the basis of the matching scores of sets of well-matched pairs of minutia.