Patent ID: 6732074
Filing Date: 2004-05-04
Classification: G10L

Abstract:
A device for speech recognition comprising:a standard dictionary; a feature extracting unit which extracts features from an input speech; a matching unit which performs matching of the features of the input speech extracted by said feature extracting unit against said standard dictionary; a result outputting unit which outputs a matching result in said matching unit; and a dictionary updating portion which updates said standard dictionary, wherein: said standard dictionary is built initially as a dictionary to be used for recognizing speeches produced by any independent speaker; said dictionary updating portion updates said standard dictionary so as to provide a dictionary to be used for recognizing speeches produced by a dependent speaker based on the result of matching of the features extracted from the input speech against said standard dictionary; and said standard dictionary is built initially as a dictionary, to be used for recognizing speeches produced by any independent speaker, as a result of standard features of each string of characters being disintegrated into phoneme units, the thus-obtained features of the respective phonemes being used as phoneme information, and the connection of the phonemes being used as path information; said matching unit, when comparing features of input phonemes determined from the features extracted from the input speech for a string of characters with the phoneme information in said standard dictionary corresponding to said string of characters, performs evaluation of phoneme distance between the features of the input phonemes and the phoneme information in said standard dictionary corresponding to said string of characters; and said dictionary updating portion, based on the result of said evaluation of phoneme distance, updates the phoneme information in said standard dictionary corresponding to said string of characters, and, thus, updates said standard dictionary so as to provide a dictionary to be used for recognizing speeches produced by a dependent speaker, wherein said dictionary updating portion updates the phoneme information in said standard dictionary corresponding to said string of characters, and, thus, updates said standard dictionary, only when the phoneme distance between the features of the input phonemes and the phoneme information in said standard dictionary corresponding to said string of characters exceeds a predetermined threshold as a result of said evaluation of phoneme distance, such that said updating portion does not update said standard dictionary when the phoneme distance between the features of the input phonemes and the phoneme information in said standard dictionary corresponding to said string of characters does not exceed said predetermined threshold.