[Asterisk-Dev] Please help test jitterbuffer/PLC patches.

[Steve Underwood]

Chris Stenton wrote:

>
> ----- Original Message ----- From: "Steve Kann" <stevek at stevek.com>
> To: "Asterisk Developers Mailing List" <asterisk-dev at lists.digium.com>
> Sent: Tuesday, March 15, 2005 7:51 PM
> Subject: Re: [Asterisk-Dev] Please help test jitterbuffer/PLC patches.
>
>
>> Michael Giagnocavo wrote:
>>
>>> But G729 still isn't supported for PLC yet?
>>> I'd love to apply it, as I've got some seriously horrendous connections
>>> (packetloss up to 10%, jitter up to 100ms sometimes).
>>>
>> I don't have this, don't know if anyone else made something like that.
>>
>> If you have the source, it should be pretty trivial to add, but I 
>> don't have the source (and I don't use G.729, so I really don't want 
>> it). If you look at the patches for speex, iLBC, etc., it's pretty 
>> simple.
>>
>
> I thought this was already in  G 729 via CELP; all you need to do is 
> pass a packet to the codec with an invalid CRC?

The basic G.729 spec does not include PLC, but one of the annexes adds 
it. I think most implementations include the annex. The PLC in that 
annex takes state information within the decoder into account. This 
results in better G.729 specific PLC than other PLC implementations are 
likely to achieve.

I think you must be confused about CRCs. There are no CRCs in the G.729 
codec.

Regards,
Steve