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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>Igor<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>The main issue is not the packets are being lost but the rendering being too slow and blocking the receive thread which would drop packets. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>The quick solution was to throw the actual rending within your VideoOutputDevice onto another thread and use a std::queue (with mutex) to load the frames coming out of the codec and grab the frames to send to the renderer. This will then not block the receiving thread.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>You can be cleaver and build a 1-3 frame buffer in your outputdevice to simulate a jitter buffer.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>See<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>MyVideoOutputDevice::SetFrameData(….,const void * mark);<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>The mark is a H323_RTPInformation pointer which contains a pointer to the last raw received RTP packet of the completed frame. You can get timestamp information from this and pace the output to the render, so if a frame is dropped then you can conceal it.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>Simon<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> h323plus-bounces@lists.packetizer.com [mailto:h323plus-bounces@lists.packetizer.com] <b>On Behalf Of </b>Igor Pavlov<br><b>Sent:</b> 08 February 2011 22:27<br><b>To:</b> h323plus@lists.packetizer.com<br><b>Subject:</b> [h323plus] lost rtp packets and using jitter for video session<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Hi,<br><br>On connection speed greater than 384 kbps I have many lost rtp packets.<br>If I switch off decoding of incoming video packets, than number of lost packets decreases.<br>That is why I would like to try use jitter on video stream.<br>I changed call of OpalMediaFormat() constructor inside OpalVideoFormat constructor in such way that needsjitter member become TRUE.<br>But It is not working, not decoding any data.<br><br>How can I use Jitter for my purpose and in general - can I do it?<br clear=all><br>Igor Pavlov<o:p></o:p></p></div></body></html>