Automatic generation of control signals for a parallel formant speech synthesizer

An algorithm to estimate formant frequencies and amplitudes has been developed to provide control signals for a parallel formant speech synthesizer. During voiced sounds power spectra are derived by Fourier analysis of speech samples in the closed glottis regions but for unvoiced sounds spectra are derived with appropriate time averaging. Each power spectrum is matched trying several different allocations of formants to spectral peaks. An analysis-by-synthesis procedure iteratively updates the formant frequencies and amplitudes for each allocation. The final choice from these formant parameters is made every 10 ms, and depends on both spectral match and speech-like constraints.