Formant extraction from Fourier transform phase

A method of extracting formant information from the short-time Fourier transform (FT) phase spectrum of speech is proposed. Fourier transform phase has not been used for formant extraction because it appears to be noisy and difficult to interpret. The effects of wrapping of phase (due to zeros close to the unit circle and the linear phase component) make it difficult to derive useful information. The authors develop algorithms to reduce the effects of wrapping.