Abstract
An adaptive transform coder is proposed that makes effective use of vector quantization. It is aimed at medium-band (4. 8-9. 6 kbps) speech coding. To minimize waveform distortion, discrete Fourier transform (DFT) coefficients of the linear prediction residue are quantized using two novel techniques: information has been adaptively allocated so as to obtain SNR gain, and quantization has been divided into two (vector-scalar) stages for a higher bit rate. Subjective quality at 7. 2 kbps in comparable to that for a 5 bit log PCM. The coder is resistant to background noise.
| Original language | English |
|---|---|
| Pages (from-to) | 87-95 |
| Number of pages | 9 |
| Journal | Reports of the Electrical Communication Laboratory |
| Volume | 34 |
| Issue number | 1 |
| Publication status | Published - 1986 Jan 1 |
| Externally published | Yes |
ASJC Scopus subject areas
- Engineering(all)