Hi Gang Lau, 2008/7/17 Gang Lau <gangban.lau at gmail.com>: > Hi, > I have some questions about conference bridge when play with pjsipua. > > If we want to create a four party audio conference, is it needed to > connect all channels each other? > > connect(0, 1); > connect(0, 2); > connect(0, 3); > connect(1, 0); > ... > connect(1,3); > connect(2,0); > ... > connect(2,3); > ... > connect(3,2); > > or just all the ports connected to port zero and port zero connected to > all ports is enough. You have to connect all channels each other. Port zero is just a participant as the other stream ports, it doesn't do the mixing, the conference bridge does. > > And it seems pjsipua create conference bridge by default, even for a > simple call. Yes, assumed you are using PJSUA, there is no pjsipua. > The conference bridge has 120ms(buffer size 6 * ptime 20 ms) latency.A > simple call will be total 240ms latency caused by > both side bridge. Is it true? > How could I reduce latency for pjsipua? > No, it isn't true :) The buffer size you point there should be PJMEDIA_SOUND_BUFFER_COUNT. Please see please see http://trac.pjsip.org/repos/wiki/FAQ#audio-latency about buffer size meaning. The link also gives info about how to reduce latency. Regards, nanang
