Method and apparatus for suppressing background music or noise from the speech input of a speech recognizer

A method for suppression of an unwanted feature from a string of input speech, comprising:

• a) providing a string of speech containing the unwanted feature, referred to as corrupted input speech;
• b) providing a reference signal representing the unwanted feature;
• c) segmenting the corrupted input speech and the reference signal, respectively, into predetermined time segments;
• d) finding for each time segment of the speech having the unwanted feature the time segment of the reference signal that best latches the unwanted feature;
• e) removing the best matching time segment of the reference signal from the corresponding time segment of the corrupted input speech;
• f) outputting a signal representing the speech with the unwanted features removed;
• wherein step (d) is performed utilizing a first filter to find the time segment of the reference signal that best matches the unwanted feature and step (e) is performed utilizing a second filter to remove the best matching time segment of the reference signal from the corresponding time segment of the corrupted input speech.

A system for suppression of an unwanted feature from a string of input speech, comprising:

• a) means for providing a string of speech containing the unwanted feature, referred to as corrupted input speech;
• b) means for providing a reference signal representing the unwanted feature;
• c) means for segmenting the corrupted input speech and the reference signal, respectively, into predetermined time segments;
• d) means for finding for each time segment of speech containing the unwanted feature the time segment of the reference signal that best matches the unwanted feature;
• e) means for removing the best matching time segment of the reference signal from the corresponding time segment of the corrupted input speech;
• f) means for outputting a signal representing the speech with the unwanted feature removed;
• wherein the finding means includes a first filter for finding the time segment of the reference signal that best matches the unwanted feature and the removing means includes a second filter for removing the best matching time segment of the reference signal from the corresponding time segment of the corrupted input speech.