COMPARISON OF SPEECH CODERS
To conclude the discussion on standardized coders, Table 4-1 [RUDK97][7] compares several coders with regard to bit rate, MOS, complexity (with G.711 as the base), and delay (frame size and lookahead time).
[7] [RUDK97] Rudkin, S., Grace, A., and Whybray, M. W. "Real-Time Applications on the Internet," BT Journal, Vol. 15, No. 2, April 1997.
| Standard | Coding type | Bit rate kbit/s | MOS | Complexity | Delay (ms) |
|---|---|---|---|---|---|
| G.711 | PCM | 64 | 4.3 | 1 | 0.125 |
| G.726 | ADPCM | 32 | 4.0 | 10 | 0.125 |
| G.728 | LD-CELP | 16 | 4.0 | 50 | 0.625 |
| GSM | RPE_LTP | 13 | 3.7 | 5 | 20 |
| G.729 | CSA-CELP | 8 | 4.0 | 30 | 15 |
| G.729A | 15 | ||||
| G.723.1 | ACELP | 6.3 | 3.8 | 25 | 37.5 |
| MP-MLQ | 5.3 | ||||
| US Dod FS1015 | LPC-10 | 2.4 | synthetic | 10 | 22.5 |
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