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<div style="">I had the same problem a while back. I also use live555 feeding libavcodec.<br>
While the standard only says you need to have a 7 and an 8 before the first 5 and that after that the 5 or 1 is valid, I have had decoding trouble because of it.<br>
So while all the following are technically legal<br>
7,8,5,1,1,1,1,5,1,1,1...<br>
7,8,5,1,1,1,1,1,1......<br>
7,8,5,5,5,1,1,1,5,1,1,1,5,1,1,1 (some axis cameras by default)<br>
<br>
It is the decoder not live555 that needs the 7,8,5 at the beginning of every key frame.
<br>
I have gotten arguments about this, It seems to vary by version. The 7 and 8 packets are so small compared to
<br>
the key frame slices [5] and the diff frames [1] that I just cache them and inject them if missing. Not only do I get<br>
Rock solid playback, I do not need to worry about a second user starting late on a multicast or trouble when I seek.<br>
<br>
BTW each and every frame needs the 0x00 0x00 0x00 0x01 (4 bytes, aka network byte order. not a 32 bit byte that could end up with endian issues)<br>
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<div style="direction: ltr;" id="divRpF329528"><font color="#000000" face="Tahoma" size="2"><b> From:</b> live-devel-bounces@ns.live555.com [live-devel-bounces@ns.live555.com] on behalf of Jesse Hemingway [jhemingw@nerdery.com]<br>
<b>Sent:</b> Friday, February 08, 2013 8:36 PM<br>
<b>To:</b> LIVE555 Streaming Media - development & use<br>
<b>Cc:</b> LIVE555 Streaming Media - development & use<br>
<b>Subject:</b> Re: [Live-devel] H.264 via RTP - ugly artifacts<br>
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<div>Interesting, thank you for the response. I actually discard all but 7, 8 and 5 frames that occur before the initial 'priming' is complete, they are just logged for completeness. So my first buffer passed is of the form [7 8 5], after which I pass all
frames willy-nilly, even the timing NAL [ 6 ]. I'm wondering if my bytestream framing is wrong? 0x000001.NAL.0x00. I read the Appendix B bytestream syntax and also the ffmpeg NAL detection code and it seems sufficient, but I've also read posts that indicated
this simple approach was incorrect.<br>
<snip></div>
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