[Asterisk-Users] G.729? Worth it?

[Aaron Johnson]

Andrew Kohlsmith wrote:

>On January 19, 2005 12:23 pm, Paul Fielding wrote:
>  
>
>>I think you might want to clarify that Best audio quality is in relation to
>>other highly compressed codecs.  Certainly my (albeit limited) experience
>>is that g711 is much more clear than g729.   Compared against gsm, for
>>example, however, the audio quality is quite good....
>>    
>>
>
>heh -- everyone keeps bashing on GSM but out of the low bitrate codecs I've 
>tried (G711, GSM, iLBC) GSM is king (G711 is the absolute upper bound of my 
>"low bitrate") 
>  
>
Since when is g711 "low bitrate"?

>it to sound good.
>
>Any ideas for additional testing would be great -- I'm not afraid of packet 
>captures or code hacking but I'm not sure where to begin at this point.  My 
>links are solid (no packet loss, low jitter, you name it) and as I said... 
>G711, GSM, ulaw... these all sound great.  It's just iLBC.
>
>-A.
>  
>
We briefly tested iLBC and found that the audio quality was not 
acceptable.  If you have the ability, you may also want to try out 
Speex.  Other than the high CPU overhead, many people here have found 
that it gives you good audio quality while using less bandwidth than 
g711 ulaw.  One of the biggest problems with Speex is finding good 
phones that support it.  Our clients mainly use Polycom and Cisco phoes, 
which do not support Speex.

-- 
Aaron Johnson
Star Networks
Main: 602-889-3000 | Office: 602-889-3002 | Cell: 602-741-4660