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--></style></head><body lang="EN-CA" link="blue" vlink="purple"><div class="WordSection1"><p class="MsoNormal">We are using Live555 to stream (unicast) short bursts of video (currently MJPG, soon to be H.264) and metadata as objects are tracked throughout a scene. For a given tracked object , we have information about the object (id, location, etc), which we send as XML meta data in a MediaSubsession. Each video/metadata sequence has a start and an end, and multiple (up to 25) of these sequences may be active at one time (think of each as coming from a separate camera trained on a separate subject).</p>
<p class="MsoNormal"> </p><p class="MsoNormal">Currently the way we are doing this (just as a proof of concept) is to use a single SMS containing one MJPG stream and one XML stream, with each video sequence multiplexed into this single image/metadata channel. In this model, the MJPG stream has the frames tagged with a serial number and put into correspondence with the XML stream in a buffer on the receiving end. </p>
<p class="MsoNormal"> </p><p class="MsoNormal">This is very clunky, and will not scale to better video codecs due to the uncorrelated (multiplexed) sequence of frames. We would like to move toward a model where we have a single session open, but each video/metadata sequence is dynamically added/removed from that session as objects appear and disappear.</p>
<p class="MsoNormal"> </p><p class="MsoNormal">Is this possible using Live555? Is this something that can’t be done due to limitations in RTSP/RTCP? </p><p class="MsoNormal"> </p><p class="MsoNormal">If this can be done, at what level can we dynamically add “streams” to an open session? Can we simply add a new ServerMediaSessions after the Unicast session has begun?</p>
<p class="MsoNormal"> </p><p class="MsoNormal">Any guidance on the “right way” to tackle this would be much appreciated.</p><p class="MsoNormal"> </p><p class="MsoNormal">Best regards,</p><p class="MsoNormal"><br>Dave McMordie</p>
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<tr><td width="157" valign="top" style="width:118.1pt;padding:0cm 0cm 0cm 0cm"><p class="MsoNormal" style="line-height:115%"><b><span style="font-size:12.0pt;line-height:115%;font-family:"Arial","sans-serif";color:black"><img width="141" height="41" id="Picture_x0020_1" src="cid:image001.jpg@01CCCBDB.C0E45E90" alt="Description: cid:image001.jpg@01C94FAF.E4535F30"></span></b><span style="font-size:12.0pt;line-height:115%;font-family:"Arial","sans-serif";color:black"><br clear="left">
</span><span style></span></p></td><td width="164" valign="top" style="width:122.9pt;padding:0cm 0cm 0cm 0cm"><p class="MsoNormal" style="line-height:115%"><b><span lang="FR-CA" style="font-family:"Arial","sans-serif";color:#403152">David McMordie</span></b><span lang="FR-CA" style="font-family:"Arial","sans-serif";color:#403152"> </span><span lang="FR-CA" style="font-family:"Arial","sans-serif""><br>
</span><i><span lang="FR-CA" style="font-size:8.0pt;line-height:115%;font-family:"Arial","sans-serif";color:black">CTO</span></i><span lang="FR-CA" style="font-family:"Arial","sans-serif";color:black"> </span><span lang="FR-CA" style></span></p>
<p class="MsoNormal" style="line-height:115%"><span lang="FR-CA" style="font-size:8.0pt;line-height:115%;font-family:"Arial","sans-serif";color:black">1751 Richardson, Suite 8.123</span><span lang="FR-CA" style></span></p>
<p class="MsoNormal" style="line-height:115%"><span style="font-size:8.0pt;line-height:115%;font-family:"Arial","sans-serif";color:black">Montreal, QC H3K 1G6</span><span style="font-family:"Arial","sans-serif";color:black"><br>
</span><span style="font-size:8.0pt;line-height:115%;font-family:"Arial","sans-serif";color:black"><a href="mailto:mcmordie@viionsystems.com"><span style="color:black">mcmordie@viionsystems.com</span></a> </span><span style="font-family:"Arial","sans-serif";color:black"><br>
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