Method and system for the reduction of processing time in a speech recognition system using the hidden markov model

摘要

Disclosed is a speech recognition method in a speech recognition apparatus to applying speech recognition to a voice signal applied thereto. The input voice signal is converted from an analog to a digital signal and sequences of feature vectors are extracted based upon the digital signal (S12). A search space is defined by the sequences of feature vectors and an HMM (16) prepared beforehand for each unit of speech. The search space allows a transition between HMMs only in specific feature-vector sequences. A search is conducted in this space to find an optimum path for which the largest acoustic likelihood regarding the voice signal is obtained to find the result of recognition (S14), and this result is output (S15).