[Asterisk-Users] Prices of g729 codec

[Steve Underwood]

Kevin P. Fleming wrote:

>----- trixter aka Bret McDanel <trixter at 0xdecafbad.com> wrote:
>
>  
>
>>speex isnt in all ATAs and other things.  So if its not there it
>>offers
>>worse compression since the call wont go through :P
>>    
>>
>
>And it's not there because it is significantly more computationally intensive than G.729 (I don't believe there is a fixed-point Speex implementation either, although I could be wrong) so that means the hardware cost for the ATA/phone/etc. goes up.
>
>  
>
There is a fixed point Speex implementation for some of the popular 
DSPs. The PC versions of Speex are not much more computationally 
expensive than G.729 these days. The fixed point versions are less well 
optimised right now, but they are getting better. G.729 tends to take 
between 10-20MIPs on a DSP, depending on the implementation and the 
architecture. Speex seems to be taking 30-40MIPs, but that should fall 
over time. The G.729 implementations for things like TI 54x have been 
very intensively optimised to get where they are today.

Asterisk should really import a recent version of Speex. The last time I 
checked it had an ancient version. Quality has improved, and computation 
has significantly reduced.

Regards,
Steve