Patent US 7,680,666

The object of the present invention is to keep a high success rate in recognition with a low-volume of sound signal, without being affected by noise.The speech recognition system comprises a sound signal processor 10 configured to acquire a sound signal, and to calculate a sound signal parameter based on the acquired sound signal; an electromyographic signal processor 13 configured to acquire potential changes on a surface of the object as an electromyographic signal, and to calculate an electromyographic signal parameter based on the acquired electromyographic signal; an image information processor 16 configured to acquire image information by taking an image of the object, and to calculate an image information parameter based on the acquired image information; a speech recognizer 20 configured to recognize a speech signal vocalized by the object, based on the sound signal parameter, the electromyographic signal parameter and the image information parameter; and a recognition result provider 21 configured to provide a result recognized by the speech recognizer 20.