Abstract
This paper describes techniques for evaluating and improving subjective quality of PSI-CELP speech coding. In low bit-rate speech coding, it is impossible to design good coders based on only objective evaluation measures such as SNR, SNRseg, and cepstral distances: subjective evaluation is essential. The PSI-CELP codec for mobile communications has been designed to be optimal under the following conditions: error free, burst error, low level power, and background noise. A perceptual weighting filter and a postfilter improve the subjective quality. The relationships between subjective and objective evaluation measures have been investigated to obtain error-robust coders. The subjective quality of the resulting half-rate PSI-CELP codec is better than that of the Japanese full-rate codec.
| Original language | English |
|---|---|
| Pages (from-to) | 405-412 |
| Number of pages | 8 |
| Journal | NTT R and D |
| Volume | 43 |
| Issue number | 4 |
| Publication status | Published - 1994 Jan 1 |
| Externally published | Yes |
ASJC Scopus subject areas
- Electrical and Electronic Engineering