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<P><FONT SIZE=2 FACE="Arial">Ok, this one is driving me buts now so I would like to throw it to the floor if I may.</FONT>
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<P><FONT SIZE=2 FACE="Courier New">To re-cap, I am trying to use VLC to playback an RTP/H263 video stream (RTP/H263 payload using RFC2429). I am giving VLC the following SDP manually as a file (which was created after several prods in the right direction by Ross Finlayson)</FONT></P>
<P><FONT SIZE=2 FACE="Courier New">v=0</FONT>
<BR><FONT SIZE=2 FACE="Courier New">o=- 7776 3 IN IP4 10.215.130.112</FONT>
<BR><FONT SIZE=2 FACE="Courier New">s=Test H263 stream</FONT>
<BR><FONT SIZE=2 FACE="Courier New">i=Parameters for the session streamed by "ChipsAhoyH263"</FONT>
<BR><FONT SIZE=2 FACE="Courier New">t=0 0</FONT>
<BR><FONT SIZE=2 FACE="Courier New">m=video 7776 RTP/AVP 98</FONT>
<BR><FONT SIZE=2 FACE="Courier New">a=rtpmap:98 H263-1998/90000</FONT>
<BR><FONT SIZE=2 FACE="Courier New">a=fmtp:98 profile=0; level=40</FONT>
<BR><FONT SIZE=2 FACE="Courier New">b=TIAS:2048000 </FONT>
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<P><FONT SIZE=2 FACE="Arial">I start the remote stream on my server which starts blasting UDP/RTP packets at port 7776 on my client machine.</FONT>
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<P><FONT SIZE=2 FACE="Arial">On the client I start vlc up like this:</FONT>
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<P><FONT SIZE=2 FACE="Arial">vlc -vvv </FONT><A HREF="file://c:\testH263.sdp"><U><FONT COLOR="#0000FF" SIZE=2 FACE="Arial">file://c:\testH263.sdp</FONT></U></A>
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<P><FONT SIZE=2 FACE="Arial">VLC comes up and after about 10 seconds(not sure why the delay is so high) it starts to playback the stream. However after about 3-4 seconds, the playback freezes and the following messages appear on the debug screen:</FONT></P>
<P><FONT SIZE=2 FACE="Arial"></FONT> <FONT SIZE=2 FACE="Courier New">ffmpeg warning: illegal ac vlc code at 2x8</FONT>
<BR><FONT SIZE=2 FACE="Courier New"> (h263@00B1E370)</FONT>
<BR><FONT SIZE=2 FACE="Courier New">ffmpeg warning: Error at MB: 98</FONT>
<BR><FONT SIZE=2 FACE="Courier New"> (h263@00B1E370)</FONT>
<BR><FONT SIZE=2 FACE="Courier New">ffmpeg debug: concealing 65 DC, 65 AC, 65 MV errors</FONT>
<BR><FONT SIZE=2 FACE="Courier New"> (h263@00B1E370)</FONT>
<BR><FONT SIZE=2 FACE="Courier New">live555 debug: lost 2048 bytes</FONT>
<BR><FONT SIZE=2 FACE="Courier New">live555 debug: increasing buffer size to 524288</FONT>
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<P><FONT SIZE=2 FACE="Courier New">The playback then resumes for similar period and then freezes again - this continues for a about 5 mins and then VLC blows up.</FONT></P>
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<P><FONT SIZE=2 FACE="Courier New">I have created the source H263 file (which I am streaming) using the Telenor h263 encoder and have verified it's validity by playing it back using ffplay (in the ffmpeg package). I am however not too sure I have got the RTP payload correct as the RFC is not exactly helpful. I simple tag on the RFC2429 2 byte header and set the P bit to 1 everytime.</FONT></P>
<P><FONT SIZE=2 FACE="Courier New">Also, I noticed that the results are quite different on linux - the live555 module in VLC simply states that there is no data to playback and gives up…very odd I thought as the windows build seems to at least read in the packets.</FONT></P>
<P><FONT SIZE=2 FACE="Courier New">Any help would be very much appreciated as I really want to use VLC for this as we want to use the transcoding facilites which look great.</FONT></P>
<P><FONT SIZE=2 FACE="Courier New">Many regards,</FONT>
<BR><FONT SIZE=2 FACE="Courier New">-Chris Dobbs</FONT>
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<P><FONT SIZE=2 FACE="Courier New">PS/</FONT>
<BR><FONT SIZE=2 FACE="Courier New">My packet sizes are around 2500 bytes so I increased the VLC MTU setting to 3000.</FONT>
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