Patent ID: 6205424
Filing Date: 2001-03-20
Classification: G10L

Abstract:
A method for verifying a claimed identity of a speaker, the method comprising the steps of:processing training speech signals to create sets of acoustic models, the training speech signals being produced by speakers having known identities during training sessions, there being one set of acoustic models for each identified speaker;selecting from the sets of acoustic models a plurality of sets of cohort models for each identified speaker, each of the plurality of sets of cohort models characterizing the speech of a corresponding identified speaker;processing testing speech signals produced by an unknown speaker claiming to be one of the identified speakers to generate processed testing speech signals during a testing session;comparing the processed testing speech signals and the set of acoustic models for the claimed identified speaker to determine first scores;comparing the processed testing speech signals and the plurality of sets of cohort models for the claimed identified speaker to determine second scores;selecting a subset of scores from the second scores, the subset of scores corresponding to sets of cohort models which characterize the testing speech signals according to a predetermined criteria;validating that the unknown speaker is the claimed identified speaker if the difference between the first scores and a predetermined combination of the subset of scores is greater than a predetermined threshold value.