Sixth European Conference on Speech Communication and Technology
This paper presents an Enhanced analysis-by-synthesis (AbS) Waveform Interpolative (EWI) speech coder at 4 kbps. The system incorporates novel features such as: AbS quantization of the slowly evolving waveform (SEW), AbS vector quantization (VQ) of the dispersion phase, a special pitch search for transitions, and switched-predictive analysis-by-synthesis gain VQ. Subjective quality tests indicate that it exceeds MPEG-4 at 4 kbps and of G.723.1 at 5.3 kbps, and it is slightly better than G.723.1 at 6.3 kbps.
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Bibliographic reference. Gottesman, Oded / Gersho, Allen (1999): "Enhanced analysis-by-synthesis waveform interpolative coding at 4 KBPS", In EUROSPEECH'99, 1443-1446.