[asterisk-users] G729: TC400B vs Software Encoder

[Steve Underwood]

On 12/05/2009 10:19 PM, Kevin P. Fleming wrote:
> Jim Boykin wrote:
>    
>> Can someone help me decide between TC400B vs Software Encoder. TC400B
>> is really expensive and would like to get opinion if it is worth
>> considering. Maximum simultaneous call we handle is hardly 10-15. Will
>> going to TC400B improves quality. Any other option then TC400B.
>>      
> All G.729 encoders produce the same quality, since they all do the same
> thing. The only difference between various encoders is the amount of
> load they play on the system CPU, cost, licensing models, etc.
>    
That's not strictly true. All fixed point G.729 encoders should produce 
a bit exact output that will match the ITU test vectors. However, most 
G.729 encoders on PCs use floating point arithmetic, and there is some 
variability in the output. It should be a pretty small difference, though.

Steve