Patent ID: 7415408

Claim:
A speech recognizing method comprising: a speech section detecting step of detecting a speech section from an input signal; a characteristic amount extracting step of analyzing an input speech, which is the input signal in the speech section, and extracting the time series of the amount of characteristics representing characteristics of the input speech; a recognizing target vocabulary comparing step of comparing the time series of the amount of characteristics with respective recognizing target vocabularies read from a recognizing target vocabulary storing unit to store predetermined recognizing target vocabularies one by one to obtain a likelihood that respective recognizing target vocabularies coincide with the time series of the amount of characteristics; an environment adaptive noise model comparing step of comparing the time series of the amount of characteristics with one recognizing standard pattern or with two or more combined recognizing standard patterns one by one to obtain a likelihood that respective environment adaptive noise models coincide with the time series of the amount of characteristics; a rejection determining step of determining whether or not the input signal is a noise by comparing the likelihood obtained by the recognizing target vocabulary comparing step with the likelihood obtained by environment adaptive noise model comparing step; and a noise model adapting processing step for calculating a first likelihood by comparing the time series of the amount of characteristics with recognizing standard patterns and orders the recognizing standard patterns in accordance with a size of the first likelihood.