Computer‐Simulated Analyzer for a Formant Vocoder

Comparative formant and channel vocoder performance

A formant vocoder based on mixtures of Gaussians

Parham Zolfaghari Tony Robinson Cambridge University Engineering Department, Trumpington Street, Cambridge CB2 1PZ, UK. Tel: [+44] 1223 332754 Fax: [+44] 1223 332662 email : psz1000,[email protected] ABSTRACT This paper describes a new low bit-rate formant vocoder. The formant parameters are represented by Gaussian mixture distributions, which are estimated from the discrete Fourier transform (...

A segmental formant vocoder based on linearly varying mixture of Gaussians

MIXTURE OF GAUSSIANS Parham Zolfaghari and Tony Robinson Cambridge University Engineering Department, Trumpington Street, Cambridge CB2 1PZ, UK. Tel: [+44] 1223 332754 Fax: [+44] 1223 332662 email : psz1000,[email protected] ABSTRACT This paper describes a low bit-rate segmental formant vocoder. The formants are estimated using mixture of Gaussians whose means are constrained to vary linearly w...

Real Time Pitch Shifting with Formant Structure Preservation Using the Phase Vocoder

Pitch shifting in speech is presented based on the use of the phase vocoder in combination with spectral whitening and envelope reconstruction, applied respectively before and after the transformation. A band preservation technique is introduced to contain quality degradation when downscaling the pitch. The transposition ratio is fixed in advance by selecting analysis and synthesis window sizes...

Phase-locked Vocoder 1. Phase Vocoder

The phase vocoder is widely used to provide high-delity time stretching or contraction of audio signals such as speech or monophonic musical passages. Two problems bedevil the re-constructive phase of this technique. First, the frequency estimate is usually multi-valued and one does not know how to choose which of the possible frequencies given by the analysis to use in resynthesis. Second, a s...