US 7,565,548 B2 · Biometric print quality assurance

Abstract

Quality of biometric prints is enhanced by any one of several different methods. In one embodiment, if a biometric print does not have a high enough quality, the biometric print is discarded. In another embodiment, a matching score is associated with the degree to which the two biometric prints match. In another embodiment, a ranking is associated with a biometric print, and the ranking is determined based upon two or more matching scores associated with the biometric print. In another embodiment, a variety of distinguishing features are derived from a given biometric print and are stored for authenticating a biometric print of a user requesting access to a secure entity. In an embodiment, a transformation is applied to at least a portion of a newly acquired biometric print to improve the match of the newly acquired biometric print to a stored biometric print.

Claims51

Dependent claims

A machine-implemented method comprising:

collecting a plurality of biometric prints,
each of the plurality of biometric prints being collected within the same session;
a portion of a body exists whose scan is included in each of the plurality of biometric prints collected;
for each of the plurality of biometric prints determining a value associated with how many unique aspects are discernable for at least one biometric print that was obtained during a current usage;
for each of the plurality of biometric prints determining whether to accept or reject the at least one biometric print based on a comparison of the value to a predetermined threshold;
for each of the plurality of biometric prints accepting or rejecting the at least one biometric print, based on the determining of whether to accept or reject;
for each of the plurality of biometric prints, at least temporarily storing the unique aspects as a representation of a set of two or more biometric prints from the plurality of biometric prints, the each biometric print being included in the set if the biometric print was accepted during the accepting or rejecting, and each biometric print not being included in the set if the biometric print was rejected during the accepting or rejecting;
and
determining whether to grant access based on a comparison of an accepted biometric print to a representation of the set of two or more biometric prints.

6 more elements

A machine-implemented method comprising:

acquiring a biometric print from a user;
determining whether to request another biometric print from the user;
if as a result of the determining, it is determined to request another biometric print, presenting a request for another biometric print to the user;
identifying distinguishing characteristics associated with the biometric print;
at least temporarily storing the distinguishing characteristics as a representation of the biometric print;
determining whether to grant access based on a comparison of a first set of distinguishing characteristics to a second set of distinguishing characteristics, one of the first set of distinguishing characteristics and the second set of distinguishing characteristics including the distinguishing characteristics of the biometric prints that were that were stored at least temporarily;
wherein
the biometric print is a first fingerprint;
the identifying includes at least
searching for bifurcations of ridges, and
searching for terminations of ridges;
and
the method further comprising:
(a) collecting a plurality of fingerprints, which includes at least collecting the first fingerprint prior to the identifying;
(b) performing the identifying and the storing for each of the plurality of fingerprints;
(c) for each of the plurality of fingerprints, discarding distinguishing characteristics not found in at least one other of the plurality of fingerprints;
(d) for each of the plurality of fingerprints, determining whether the distinguishing characteristics are fewer in number than a threshold number;
(e) discarding those of the plurality of fingerprints having fewer distinguishing characteristics than the threshold number;
(f) computing matching scores for each of a plurality of pairs of fingerprints, wherein
each fingerprint of each of the plurality of pairs is one of the plurality of fingerprints,
each fingerprint of the each of the plurality of pairs is a member of more than one pair, and
each matching score is a value based upon a degree to which distinguishing characteristics of one fingerprint of the pair matched distinguishing characteristics of another fingerprint of the pair;
(g) computing at least one transformation including at least computing a rotation and computing a translation, wherein
the transformation computed is at least in part based on whether an improvement in matching indicated by the matching score results from the transformation,
a value of the translation in any direction could be positive, negative, or zero,
a value of the rotation could be positive, negative, or zero, and
the value of each matching score that is retained is a value resulting after the transformation is finished being computed;
(h) for each of the plurality of fingerprints not discarded computing a ranking based on each matching score associated with that fingerprint;
and
(i) discarding one or more of the plurality of fingerprints having rankings indicating poorer matches with others of the plurality of fingerprints than those of the plurality of fingerprints not discarded.

27 more elements

A machine-implemented method comprising:

acquiring a biometric print from a user;
determining whether to request another biometric print from the user;
if as a result of the determining, it is determined to request another biometric print, presenting a request for another biometric print to the user;
identifying distinguishing characteristics associated with the biometric print;
and
at least temporarily storing the distinguishing characteristics as a representation of the biometric print;
determining whether to grant access based on a comparison of a first set of distinguishing characteristics to a second set of distinguishing characteristics, one of the first set of distinguishing characteristics and the second set of distinguishing characteristics including the distinguishing characteristics of the biometric prints that were that were stored at least temporarily;
the determining whether to request another biometric print includes at least determining whether a particular number of biometric prints were acquired, if less biometric prints were acquired than the particular number, the presenting of the request is performed;
prior to the determining of whether the particular number of biometric prints were acquired, determining whether the biometric print acquired via the acquiring is equal to or above a particular quality and if the biometric print is below the particular quality, discarding the biometric print and further, the determining does not include the biometric print in the number of biometric prints acquired;
the particular number being three or greater, the method further comprising:
after the particular number of biometric prints has been acquired,
comparing each biometric print acquired to other biometric prints acquired by comparing the distinguishing characteristics of the biometric print to other biometric prints,
if it is determined by the comparing of the distinguishing characteristics that a distinguishing characteristic appears in a first biometric print, but does not appear in at least one other biometric print, removing the distinguishing characteristic from the biometric prints and
determining a matching score for each pair of biometric prints compared,
determining a ranking for each biometric print based on the matching scores, for any given ranking of a given biometric print, the given ranking being a associated with a combination of at least a plurality of matching scores computed from a plurality of pairs of biometric prints, any given pair of biometric prints of the plurality of pairs includes the given biometric print and one biometric print that is not included in any other of the pairs of biometric prints from which the plurality of matching scores are computed that form the combination that the given ranking is associated with;
determining which biometric print has a ranking that is lower than the other biometric prints,
removing the biometric print that has the ranking that is lower than the other biometric prints.

14 more elements

A machine-implemented method comprising:

collecting a plurality of biometric prints,
each of the plurality of biometric prints being collected from the same body;
each of the plurality of biometric prints being collected within the same session;
a portion of the body exists whose scan is included in each of the plurality of biometric prints collected
for each of the plurality of biometric prints applying a process for extracting distinguishing characteristics;
for a current unique aspect of a current biometric print, which is one of the distinguishing characteristics of the plurality of biometric prints, computing matching scores indicating a degree of match between the current distinguishing characteristic of the current biometric print and at least one distinguishing characteristic for each of the plurality of biometric prints other than the current biometric print;
repeating the computing of the matching scores for each of the distinguishing characteristics of the current biometric print;
determining which of the distinguishing characteristics to store as a representation of the current biometric print based on the matching scores of the distinguishing characteristics;
and
storing the distinguishing characteristics that were determined to be the distinguishing characteristics to store as a representation of the current biometric print;
and
determining whether to grant access based on a comparison of a first set of distinguishing characteristics to a second set of distinguishing characteristics, one of the first set of distinguishing characteristics and the second set of distinguishing characteristics including the distinguishing characteristics of the biometric prints that were that were stored.

9 more elements

Dependencies are inferred from the claim text.

Biometric print quality assurance

Life of this patent

Biometric print quality assurance

Life of this patent

Abstract

Claims51