Measuring pitch and formant frequencies for a speech understanding system
D.W. Tufts, S. Levinson, R Rao · 2005
We present new techniques for the measurement of pitch period and formant frequencies. Individual pitch periods are estimated by finding local maxima in the power spectrum averaged over a frequency band that includes a formant. A spectral analysis is then performed for each pitch period over a data interval that is of shorter duration than the estimated pitch period. The pitch synchronous spectral analysis followed by post detection smoothing - preferably carried out over both time and frequency - leads to a spectrogram from which formant trajectories can be estimated by simple algorithms.