Re: [codec] #16: Delay factor: algorithmic delay vs. transmission latency.

[Mikael Abrahamsson <[e-mail]>]

On Sun, 16 May 2010, Christian Hoene wrote:

> At the first glance, I did see evidence for the 3x factor for IP 
> gateways. The best in class at a 40.4 ms one-way delay for G.711 (20ms 
> packets) and a 54.3 ms delay for G.729 (20ms packets) referring to 
> Tables 4.1 and 4.2. The algorithmic delay of G.729 is 15ms (5ms 
> lookahead).  Thus, the algorithmic delay was 20ms for G.711 (plus an 
> unknown delay of PLC) and 25ms for G.729. Thus, a factor of 3 seems to 
> be valid (5msx2,9=53,3-40,4)

One-way delay of 40.4ms for G.711 sounds like 20ms for packet size and 
20ms for jitter buffer. I wouldn't call that "algorithmic delay", that's 
packet and jitter buffer delay, "algorithmic delay" for G.711 should be 
"zero" or am I getting the concepts wrong (since it doesn't do any 
compression).

-- 
Mikael Abrahamsson    email: [e-mail]