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<DIV id=IncrediOriginalMessage><I>-------Original Message-------</I></DIV>
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<DIV dir=ltr style="FONT-SIZE: 11pt" <i><B>From:</B></I> <A href="mailto:x264-devel@videolan.org">x264-devel@videolan.org</A></DIV>
<DIV dir=ltr style="FONT-SIZE: 11pt" <i><B>Date:</B></I> 01/17/07 06:28:43</DIV>
<DIV dir=ltr style="FONT-SIZE: 11pt" <i><B>To:</B></I> <A href="mailto:x264-devel@videolan.org">x264-devel@videolan.org</A></DIV>
<DIV dir=ltr style="FONT-SIZE: 11pt" <i><B>Subject:</B></I> [x264-devel] Re: Error Concealment</DIV></DIV>
<DIV> </DIV>
<DIV>On Wednesday 17 January 2007 09:53, Awadh Bihari wrote:</DIV>
<DIV>> Please let me know how to detect the slice loss at the decoder side.</DIV>
<DIV>> It can only be detected if active sps/pps is not equal to sps/pps ?</DIV>
<DIV> </DIV>
<DIV>Due to arbitrary slice order and the fact that slice headers do not tell you</DIV>
<DIV>how many macroblocks are in the slice (and assuming you are receiving the</DIV>
<DIV>video data over a network), I believe that the only way is to actually</DIV>
<DIV>decode each slice and count the number of macroblocks that it contributes</DIV>
<DIV>to a picture. Then, after a suitable period of time to allow late packets</DIV>
<DIV>to arrive, if you still haven't decoded all the macroblocks of a picture</DIV>
<DIV>then you have lost some slices.</DIV>
<DIV> </DIV>
<DIV>It's not particularly pretty and in fact it is probably better to get the</DIV>
<DIV>network protocol (e.g. RTP) to tell you about missing packets rather than</DIV>
<DIV>waiting to discover them in the decoding.</DIV>
<DIV> </DIV>
<DIV>Cheers,</DIV>
<DIV>-Ryan</DIV>
<DIV> </DIV>
<DIV>--</DIV>
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