A model (296, 630) is provided for formants found in human speech. Under one aspect of the invention, the model is used in formant tracking by providing probabilities that describe the likelihood that a candidate formant is actually a formant in the speech signal. Other aspects of the invention use this formant tracking to improve the model (296, 630) by regenerating the model based on the formants detected by the formant tracker (287). Still other aspects of the invention use the formant tracking to compress a speech signal by removing some of the formants from the speech signal. A further aspect of the invention uses the formant model (630) to synthesize speech. Under this aspect of the invention, the formant model (630) is used to identify a most likely formant track for the synthesized speech. Based on this track, a series of resonators (632, 634, 636) are used to introduce the formants into the speech signal.
FORMANT TRACKING IN SPEECH SIGNAL WITH PROBABILITY MODELS