Hi Paul & List, I've just implemented PTT/SQU over RTP for a client. The big advantaged are: * you can negotiate an additional dynamically numbered payload type through SDP (e.g 102/radio-event), just like RFC2833 DTMF is. That way you only send your events to peers that advertise it, and stay fully standard compliant and compatible to other SIP devices. * it's guaranteed to be in sync w/the voice data. * at 8kHz for G711 and some processing delays, you can stay well below 50ms end-to-end latency, which is usually good enough. RTCP isn't really that ideal I think... you have to attach your custom data to sender/receiver reports, which messes up the reporting intervals. I'll see if I can publish patches of the relevant changes in the media layer -- there wasn't much to do, really, i pretty much followed what's done for DTMF. hope that helps, Klaus On May 13, 2009, at 7:04 AM, manjeet wrote: > > TBCP messages are currently not supported by the PJMedia stack. I > had a similar problem where i needed to use TBCP(RTCP APP) msgs for > a similar kind of PTT application. So had to hack around by defining > my own callbacks at the application level and letting the PJMedia > stream layer call it after passing the needed PKT from the transport > layer. > > Regards > Manjeet > > > --- On Tue, 5/12/09, Olle Frimanson <olle.frimanson at keystream.se> > wrote: > From: Olle Frimanson <olle.frimanson@xxxxxxxxxxxx> > Subject: Re: Push To Talk Implementation > To: "'pjsip list'" <pjsip at lists.pjsip.org> > Date: Tuesday, May 12, 2009, 11:40 PM > > Hi Paul, we have looked into this and tried both SIP based and RTPC > based solution and the conclusions so far is that it must be based > on RTCP otherwise you will get to long delays on floor control > mechanism. > > > The next step for us is to implement TBCP or similar to do this. > > > Hopes this helps. > > > Cheers / Olle > > > From: pjsip-bounces@xxxxxxxxxxxxxxx [mailto:pjsip-bounces at lists.pjsip.org > ] On Behalf Of Paul Mungai > Sent: den 12 maj 2009 18:42 > To: pjsip at lists.pjsip.org > Subject: Push To Talk Implementation > > > Hello Everyone, > > I would like to implement PTT using the pjsip stack; how can i do > it? I want a software solution so muting/unmuting the mic is not in > my options. > > Thank you. > > Paul Mungai, > Software Engineer, > Worked on Failed & Successful projects. > > Cell: +254-738-138556 | +254-716-444781 > Blog: http://paulmungai.wordpress.com > LinkedIn: http://www.linkedin.com/in/paulmungai > Jay Leno - "Don't forget Mother's Day. Or as they call it in > Beverly Hills, Dad's Third Wife Day." > > _______________________________________________ > Visit our blog: http://blog.pjsip.org > > pjsip mailing list > pjsip at lists.pjsip.org > http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org > > _______________________________________________ > Visit our blog: http://blog.pjsip.org > > pjsip mailing list > pjsip at lists.pjsip.org > http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.pjsip.org/pipermail/pjsip_lists.pjsip.org/attachments/20090513/2c81a167/attachment.html>
