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<DIV><SPAN class=508544910-28032012>Good afternoon,</SPAN></DIV>
<DIV><SPAN class=508544910-28032012></SPAN> </DIV>
<DIV><SPAN class=508544910-28032012>I have hit an interesting obstacle while
streaming RTSP video data from a live source. I am using the openRTSP client to
retreive data from a testOnDemandRTSPServer, which I have added a new
OnDemandServerMediaSubsession type to, named OnDemandVideoInputSubsession. I am
streaming mpeg4 elementaary stream data (format: 96) and have come across a
strange problem. When ServerMediaSession::generateSDPDescription is called, I
trace the call stack from there down to the
OnDemandServerMediaSubsession::getAuxSDPLine(RTPSink *, FramedSource *)
function, which internally calls MPEG4ESVideoRTPSink::auxSDPLine(). At the
point where the getAuxSDPLine function is called, the RTPSink * and FramedSource
* parameters point to the correct classes. When entering the
MPEG4ESVideoRTPSink::auxSDPLine() function the mp4 video rtpsink checks a
variable named fSource, which should point to the FramedSource parameter from
the preceding call, yet the parameter is not passed in from the getAuxSDPLine
function. Is this a bug, or is there another way that the fSource parameter gets
set? Currently the fSource parameter is NULL so the function returns
prematurely. Without the parameter being set, my SDP description which gets
sent to the client is incomplete and is missing the line which should read
"a=fmtp:96 profile-level-id=3; ...". As a result I can connect to the stream,
with any rtsp client (openRTSP and VLC for instance) but cannot decode the
resulting data for lack of information. I do not want to edit the code in-place,
since this is part of the live555 library, any suggestions to pass the
parameters from OnDemandServerMediaSubsession::getAuxSDPLine(RTPSink *,
FramedSource *) to MPEG4ESVideoRTPSink::auxSDPLine() , or to set the fSource
parameter without destroying the live555 code?</SPAN></DIV>
<DIV><SPAN class=508544910-28032012></SPAN> </DIV>
<DIV><SPAN class=508544910-28032012>Thank you</SPAN></DIV>
<DIV><SPAN class=508544910-28032012>Regards</SPAN></DIV>
<DIV align=left><STRONG>___________________________________</STRONG></DIV><BR>
<DIV align=left><STRONG>Shaheed Abdol</STRONG></DIV>
<DIV align=left><FONT color=#909090 size=1><STRONG>Web: <A
href="http://www.scansoft.co.za/">www.scansoft.co.za</A></DIV>
<DIV align=left><FONT color=#909090 size=1><STRONG>Tel: +27 21 913
8664</STRONG></FONT></DIV>
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