Speech compression by vector quantization of epochs

Abstract

A pitch epoch is a fundamental unit of voiced speech. This paper introduces a speech compression method based on vector quantization of epochs. Pitch determination, epoch marking, vector quantization procedure, and a technique for epoch extrapolation are described. The compression method is then evaluated and briefly compared to other waveform coders. The quality is objectively measured by the segmental signal-to-noise ratio and the results are tabulated. The (automatic) epoch vector quantization yields the following SNRseg: 10.03 dB at 12.0 kbps, 11.35 dB at 21.3 kbps, 13.31 dB at 39.7 kbps, 18.32 dB at 76.4 kbps, and 62.69 dB at 112.9 kbps.