Patent attributes
A method of authenticating a finger against a stored template and expanding the stored template. The method comprises acquiring a present fingerprint image; retrieving a stored enrollment representation, comprising said stored template, and a representation of at least a first previous fingerprint image acquired in connection with a previous failed authentication attempt; and determining if the stored template should be expanded. When it is determined that a first match between a present fingerprint image representation and the stored template fulfills a first template updating requirement and a second match between the present fingerprint image representation and said at least first previous fingerprint image representation fulfills said second template updating requirement, a signal indicating a successful authentication is provided; and a first expanded template is formed based on said stored template, said present fingerprint image and said at least first previous fingerprint image.
