Patent ID: 7366669

Claim:
An acoustic model creation method to create a syllabic HMM (Hidden Markov Model) which is an acoustic model, comprising: generating a phoneme HMM set which includes phoneme HMMs corresponding to individual phonemes; combining the phoneme HMMs of the phoneme HMM set so as to generate an initial phoneme-connected syllable HMM set which includes initial phoneme-connected syllable HMMs corresponding to individual syllables; training the initial phoneme-connected syllable HMM set, thereby generating a phoneme-connected syllable HMM set being the acoustic model; and conducting a preliminary experiment for the phoneme-connected syllable HMM set by using training speech data, any misrecognized syllable and a syllable connected to the misrecognized syllable being checked using results of the preliminary experiment and syllable label data prepared in correspondence with the training speech data, a combination between a correct answer syllable for the misrecognized syllable and a syllable connected to the misrecognized syllable being extracted as a syllable connection, that a syllable-connected HMM corresponding to the syllable connection being added into the phoneme-connected syllable HMM set so as to generate an initial phoneme-connected syllable HMM/syllable-connected HMM set, and then the initial phoneme-connected syllable HMM/syllable-connected HMM set being trained using the training speech data and the syllable label data, thereby generating a phoneme-connected syllable HMM/syllable-connected HMM set being the acoustic model, the numbers of times of misrecognition of such syllable connections in the preliminary experiment results being counted, and that, a syllable-connected HMM corresponding to any syllable connection whose number of times of misrecognition is at least a preset number, among the syllable connections extracted using the preliminary experiment results, is made a candidate for addition into the phoneme-connected syllable HMM set.