Feature-Based Matcher for Distorted Fingerprint Matching
AssigneeMorphoTrack, LLC
InventorsPeter Zhen-Ping Lo, Hui Chen
Life of this patent
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Abstract
In one aspect, methods that use a novel representation, referred to as an octant feature vector (OFV), are used for matching distorted fingerprints. For instance, a feature-based matcher for distorted fingerprint matching may use a two-step local and global matching scheme to compare a set of feature vectors that are derived from minutiae of a reference fingerprint and a search fingerprint. The relative geometric relationships between the reference minutia and nearest minutiae may be derived and encoded into a feature vector based on orientation difference. The OFV is invariant to the rigid transformations and is insensitive to nonlinear distortions since the relative geometric relationships are independent from the rigid transformation.
Claims20
A method performed by one or more computers, the method comprising:
- identifying a geometrically aligned region between a search fingerprint image and a reference fingerprint image;
- determining a set of globally aligned mated minutia pairs based on the geometrically aligned region between the search fingerprint image and the reference fingerprint image;
- for each mated minutia pair included in the set of globally aligned mated minutia pairs:
- computing a first score representing a feature difference between (i) a search minutia and (ii) reference minutiae included in a set of reference minutiae that are identified as being closest neighboring minutiae to the search minutia in the geometrically aligned region, and
- computing a second score representing a ratio of a number of paired mated minutiae in the geometrically aligned region included in the set of reference minutiae relative to a number of paired unmated minutiae in the geometrically aligned region included in the set of reference minutiae;
- computing a match similarity score between the search fingerprint image and the reference fingerprint image based at least on the first score and the second score;
- and
- providing the match similarity score for output.
A system comprising:
- one or more computers;
- and
- one or more storage devices storing instructions that are operable, when executed by one or more computers, to cause the one or more computers to perform operations comprising:
- identifying a geometrically aligned region between a search fingerprint image and a reference fingerprint image;
- determining a set of globally aligned mated minutia pairs based on the geometrically aligned region between the search fingerprint image and the reference fingerprint image;
- for each mated minutia pair included in the set of globally aligned mated minutia pairs:
- computing a first score representing a feature difference between (i) a search minutia and (ii) reference minutiae included in a set of reference minutiae that are identified as being closest neighboring minutiae to the search minutia in the geometrically aligned region, and
- computing a second score representing a ratio of a number of paired mated minutiae in the geometrically aligned region included in the set of reference minutiae relative to a number of paired unmated minutiae in the geometrically aligned region included in the set of reference minutiae;
- computing a match similarity score between the search fingerprint image and the reference fingerprint image based at least on the first score and the second score;
- and
- providing the match similarity score for output.
A non-transitory machine-readable data storage device that stores instructions that, when executed by a data processing apparatus, cause the data processing apparatus to perform operations comprising:
- identifying a geometrically aligned region between a search fingerprint image and a reference fingerprint image;
- determining a set of globally aligned mated minutia pairs based on the geometrically aligned region between the search fingerprint image and the reference fingerprint image;
- for each mated minutia pair included in the set of globally aligned mated minutia pairs:
- computing a first score representing a feature difference between (i) a search minutia and (ii) reference minutiae included in a set of reference minutiae that are identified as being closest neighboring minutiae to the search minutia in the geometrically aligned region, and
- computing a second score representing a ratio of a number of paired mated minutiae in the geometrically aligned region included in the set of reference minutiae relative to a number of paired unmated minutiae in the geometrically aligned region included in the set of reference minutiae;
- computing a match similarity score between the search fingerprint image and the reference fingerprint image based at least on the first score and the second score;
- and
- providing the match similarity score for output.
Dependencies are inferred from the claim text.