Method for speech recognition, apparatus for the same, and voice controller
AssigneeMatsushita Electric Industrial Co., Ltd.
InventorsKeiko Morii, Yoshio Ohno
Life of this patent
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Abstract
An acoustic analysis unit acoustically analyzes a first utterance by a user. A pattern by-characteristic selection unit selects a trained pattern optimal for the user's utterance from a plurality of trained patterns that are previously classified and stored every characteristic. A speaker adaptation processor determines a spectral frequency distortion coefficient for correcting difference between spectral frequencies. The difference is caused by vocal tract length of a training speaker and an input speaker. Recognition of subsequent utterances using this determination improves recognition performance of the subsequent speech sounds.
Claims36
A speech recognition method comprising the steps of:
- (a) selecting, based on a first utterance by a speaker, adaptable trained patterns from a plurality of stored trained patterns, the plurality of stored trained patterns are classified by a characteristic of a training speaker;
- (b) finding a distortion coefficient fixed by spectral region of speech for an utterance by the speaker, based on the first utterance by the speaker and the selected trained patterns;
- and
- (c) recognizing an input speech sound following the first utterance by using the selected trained patterns and the distortion coefficient.
A speech recognition apparatus comprising:
- (a) an acoustic analysis unit for acoustically analyzing an input speech sound to find acoustic parameters;
- (b) a pattern by-characteristic storage for previously holding a plurality of trained patterns classified by characteristic of a training speaker;
- (c) a pattern by-characteristic selection unit for selecting adaptable trained patterns from the plurality of trained patterns based on a first utterance by a speaker;
- (d) a speaker adaptation processor for finding a distortion coefficient fixed by spectral region of speech for acoustic parameters of the first utterance by the speaker using the acoustic parameters and the trained patterns selected by said pattern selection unit;
- and
- (e) a word lexicon including known words to be recognized;
- (f) a speech recognition unit for recognizing an input speech sound following the first utterance using the distortion coefficient, the selected trained patterns and the word lexicon.
A voice controller comprising:
- (a) a sound input unit for receiving a speech sound;
- (b) an acoustic analysis unit for acoustically analyzing the speech sound from said sound input unit to provide acoustic parameters;
- (c) a pattern by-characteristic storage for previously holding a plurality of trained patterns classified by characteristic of a training speaker;
- (d) a pattern by-characteristic selection unit for selecting adaptable trained patterns from the plurality of trained patterns based on a first utterance by a speaker;
- (e) a speaker adaptation processor for obtaining a distortion coefficient fixed by spectral region of speech for acoustic parameters of the first utterance by the speaker, using the acoustic s and the trained patterns selected by said pattern selection unit;
- (f) a word lexicon comprising known words for recognition objects;
- (g) a speech recognition unit for recognizing an input speech sound following the first utterance using
- (g1) the distortion coefficient,
- (g2) the selected trained patterns, and
- (g3) the word lexicon;
- and
- (h) a control signal output unit for outputting a control signal from said speech recognition unit.
Dependencies are inferred from the claim text.