Method and apparatus for automatically updating estimates of undesirable components of the speech signal in a speech recognition system

摘要

A speech recognition method and apparatus take into account a system transfer function between the speaker and the recognition apparatus. The method and apparatus update a signal representing the transfer function on a periodic basis during actual speech recognition. The transfer function representing signal is updated about every fifty words as determined by the speech recognition apparatus. The method and apparatus generate an initial transfer function representing signal and generate from the speech input, successive input frames which are employed for modifying the value of the current transfer function signal so as to eliminate error and distortion. The error and distortion occur, for example, as a speaker changes the direction of his profile relative to a microphone, as the speaker's voice changes or as other effects occur that alter the spectra of the input speech frames. The method is automatic and does not require the knowledge of the input words or text.