Hi David,

On Fri, Feb 6, 2009 at 11:52 PM, D. S. <[email protected]> wrote:
> As it stands, G.722 sessions will not connect using Recon with sipXtapi.
> The reason is that G.722 sessions are negotiated with 8000 as the
> sample rate even though it actually operates at 16000.
> See sec. 4.5.2 in RFC3551 and the following link:
> http://en.wikipedia.org/wiki/G.722

Yes, this is a known problem, and it's already workarounded in
sipXtapi. Look at following lines:
sipXtackLib\src\net\SdpBody.cpp:1272
sipXtackLib\src\net\SdpBody.cpp:1778
sipXtackLib\src\net\SdpHelper.cpp:220

So if it does not work with recon, it's a problem with recon I guess.
I recall I tested this with some phones and it worked.

> My patch also changes the default internal sample rate of the codec to
> get it working with the default internal sipXtapi sample rate of 8000.

It's a very different patch, please do not mix several changes into
a single one. You can use things like Mercurial queues to maintain
sets of patches.

Please, upload clean version of this patch to http://codereview.appspot.com/
Choose "sipXtapi/main branch" and add me (Alexander.Chemeris)
as a reviewer.

Actually we should pass flowgraph samplerate to a codec
to let it choose the best output samplerate. But this require
quite a few of changes in codec API.

> How do you build sipXtapi to use an internal sample rate of 16000?

Added this to FAQ:
http://sipxtapi.sipfoundry.org/wiki/Frequently_Asked_Questions

-- 
Regards,
Alexander Chemeris.

SIPez LLC.
SIP VoIP, IM and Presence Consulting
http://www.SIPez.com
tel: +1 (617) 273-4000
_______________________________________________
sipxtapi-dev mailing list
[email protected]
List Archive: http://list.sipfoundry.org/archive/sipxtapi-dev/

Reply via email to