Patent ID: 9483679
Filing Date: 2016-11-01
CPC Classification: G06K,G06T

Claim Text:
1. A method of enrolling a fingerprint comprising: receiving a first fingerprint image strip, a second fingerprint image strip and a third fingerprint image strip, each fingerprint image strip representing a portion of the fingerprint and the second and third fingerprint image strips overlapping the first fingerprint image strip, wherein the fingerprint image strips are input using a swipe-type fingerprint sensor having a rectangular scan area where a width of a long side thereof is less than 10 mm; extracting minutiae from each of the first, second and third fingerprint image strips; matching the extracted minutiae of the first, second and third fingerprint image strips to determine relative positions of the fingerprint image strips; combining the minutiae of the first, second and third fingerprint image strips based on their relative positions to produce a combined set of minutiae representing a larger portion of the fingerprint; and determining that the fingerprint has been successfully enrolled if a width of the larger portion of the fingerprint is greater than a predetermined minimum width; wherein matching the extracted minutiae of at least two of the first, second and third fingerprint image strips comprises: determining a first local neighbourhood for each extracted minutiae of one of the fingerprint image strips and for each extracted minutiae of another of the fingerprint image strips, wherein each first local neighbourhood includes at least one extracted minutia neighbouring the respective extracted minutia; comparing the first local neighbourhoods of the extracted minutiae of the one of the fingerprint image strips with the first local neighbourhoods of the extracted minutiae of the other of the fingerprint image strips to determine matched minutiae appearing in both the extracted minutiae of the one of the fingerprint image strips and the extracted minutiae of the other of the fingerprint image strips; determining a second local neighbourhood for each unmatched extracted minutiae of the one of the fingerprint image strips and in the other of the fingerprint image strips, wherein each extracted minutia that is not a matched minutia is an unmatched extracted minutia, and wherein each second local neighbourhood includes at least one matched minutia neighbouring the respective unmatched extracted minutia; comparing the second local neighbourhoods of the unmatched extracted minutiae of the one of the fingerprint image strips with the second local neighbourhoods of the unmatched extracted minutiae of the other of the fingerprint image strips to determine further matched minutiae appearing in both the extracted minutiae of the one of the fingerprint image strips and the extracted minutiae of the other of the fingerprint image strips, wherein the relative position of fingerprint image strips is determined also based on the further matched minutia.