[Speex-dev] size of speex packets when VAD/CNG is enabled

[Fabio Pietrosanti (naif)]

Hi all,

supposing to have speex working at 3.95, when VAD/CNG is employed, which 
is the size of those "silence" samples respect to voice samples?

I am wondering if it could be possible to lower even the transmission of 
VAD/CNG samples by specifying "outbound" in the communication channel 
only 1 bit instead of sending the whole VAD/CNG packet.

I am doing the same for AMR where i strip-off the AMR SID describing 
VAD/CNG and simply send "1 bit" in a custom appropriate header of the 
transmission protocol. With AMR 4.75, sample of 13byte, additionally i 
also cut-off the the 1byte AMR header by making AMR samples to be 
transmitted of 12byte.

Are those kind of "bandwidth" optimization feasible also for speex?

a) size of VAD/CNG samples being replaced by "1 bit" instead of 
transporting the whole sample
b) cutting-off the speex header to reduce the sample size (and 
re-attaching it a standard-one on the other side before playing)

I don't know if the first (a) or the second (b) would be feasible or 
would cause problems.

Fabio

p.s. i am talking about a voip application