SPEAKER ADAPTATION METHOD FOR ACOUSTIC MODEL AND DEVICE THEREFOR

摘要

PURPOSE: To realize a recognition system of high performance which minimizes the error rate of an acoustic HMM. CONSTITUTION: This device has a characteristic parameter extraction section 1 which forms and holds the acoustic HMM(hidden Markov model) 6 for nonspecific speakers formed by learning from the speeches of many speakers and extracts a characteristic parameter from speech data 5 of the person to be recognized and a likelihood maximizing adaptation section 2 which optimizes the parameter of the acoustic HMM for the nonspecific persons so as to maximize the likelihood for the speech of a person to be recognized. Further, the device has an identification error minimizing adaptation section 3 which obtaines the acoustic HMM of the min. in the identification error by defining the differentiable loss function from the parameter of the acoustic HMM having the parameter maximized in the likelihood and the time series speech data of the characteristic parameter of the person to be recognized and selecting the parameter so as to minimize the function and an adaptation acoustic HMM accumulation section 4.