Speech recognition apparatus, speech recognition method, and computer-readable recording medium in which speech recognition program is recorded

A speech recognition method of recognizing at least one of keywords contained in uttered spontaneous speech, comprising:

• an extraction process of extracting a spontaneous-speech feature value, which is feature value of speech ingredient of the spontaneous speech, by analyzing the spontaneous speech;
• an acquiring process of acquiring at least one of keyword feature data indicating feature value of speech ingredient of said keyword and at least one of an extraneous-speech feature data indicating feature value of speech ingredient of extraneous-speech, said keyword feature data and extraneous-speech feature data prestoring in a database;
• a calculation process of calculating likelihood which indicates probability that at least part of the feature values of the extracted spontaneous speech is matched with said keyword feature data and said extraneous-speech feature data;
• and
• a determination process of determining at least one of said keywords to be recognized and said extraneous-speech based on the calculated likelihood,
• wherein said calculation process calculates the likelihood by using a predetermined correction value when said calculation process calculates the likelihood which indicates probability that at least part of the feature values of the extracted spontaneous speech is matched with said extraneous-speech feature data.

A recording medium wherein a speech recognition program is recorded so as to be read by a computer, the computer included in a speech recognition apparatus for recognizing at least one of keywords contained in uttered spontaneous speech, the program causing the computer to function as:

• an extraction device for extracting a spontaneous-speech feature value, which is feature value of speech ingredient of the spontaneous speech, by analyzing the spontaneous speech;
• an acquiring device for acquiring at least one of keyword feature data indicating feature value of speech ingredient of said keyword and at least one of an extraneous-speech feature data indicating feature value of speech ingredient of extraneous-speech, said keyword feature data and extraneous-speech feature data prestoring in a database;
• a calculation device for calculating likelihood which indicates probability that at least part of the feature values of the extracted spontaneous speech is matched with said keyword feature data and said extraneous-speech feature data;
• and
• a determining device for determining at least one of said keywords to be recognized and said extraneous-speech based on the calculated likelihood,
• wherein said calculation device calculates the likelihood by using a predetermined correction value when said calculation device calculates the likelihood which indicates probability that at least part of the feature values of the extracted spontaneous speech is matched with said extraneous-speech feature data.