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<P><FONT SIZE=2 FACE="Arial">Sorry to be a pain but can anyone verify that the following assumtions are correct when packetising H263 into RTP packets</FONT></P>
<P><FONT SIZE=2 FACE="Arial">Caveat here is that I have the H263 data in a file (hence I don't know what size each indivual h263 encoded frame is) and am reading this in to stream out to VLC </FONT></P>
<P><FONT SIZE=2 FACE="Arial">1. The first packet shall have the h263 header P bit set to one. (bit 6)</FONT>
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<P><FONT SIZE=2 FACE="Arial">2. Subsequent packets shall have P bit set to zero</FONT>
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<P><FONT SIZE=2 FACE="Arial">3. When a record from the file contains a start of next frame marker (which I am assuming is the 2 bytes of zeros I see sprinkled thoughout the file ) I set the M bit in the RTP header to signal end of frame for current frame.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">I am struggling to understand how to correctly packetise as I get 'some' results by playing this stream with VLC but it seems to taking far too long in the RTP/demux stage before actually attempting to display frames - I get errors like this:</FONT></P>
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<P><FONT COLOR="#000000" SIZE=1 FACE="MS Shell Dlg 2">main error:</FONT> <FONT COLOR="#FF0000" SIZE=1 FACE="MS Shell Dlg 2">picture 00BDBD98 refcount is -1</FONT>
<BR><FONT COLOR="#000000" SIZE=1 FACE="MS Shell Dlg 2">ffmpeg warning:</FONT> <FONT COLOR="#0000FF" SIZE=1 FACE="MS Shell Dlg 2">Error at MB: 3</FONT>
<BR><FONT COLOR="#0000FF" SIZE=1 FACE="MS Shell Dlg 2"> (h263@00B1E370)</FONT>
<BR><FONT COLOR="#000000" SIZE=1 FACE="MS Shell Dlg 2">ffmpeg debug: concealing 99 DC, 99 AC, 99 MV errors</FONT>
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<P><FONT SIZE=2 FACE="Arial">The video sequence freezes at this point but continues again after 3-5 sec, then does the same</FONT>
<BR><FONT SIZE=2 FACE="Arial">I suspect the demuxer is grabbing in RTP packets and not knowing when the eof frame is so it just keep gobbling them up and when it's buffer is full it hands them off to the h263 decoder…?!!</FONT></P>
<P><FONT SIZE=2 FACE="Arial">I used RFC4269 as a reference but it reads like stereo instructions and seems to assumeI understand the H263 encoder which I don't. It states that the P bit is start of picture marker but what does this mean? Start of entire h263 video sequence or start of frame which is comprosed of some unknown number of coded blocks?</FONT></P>
<P><FONT SIZE=2 FACE="Arial">Help please….</FONT>
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<P><FONT SIZE=2 FACE="Arial">-Chris</FONT>
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