Problem with H.264 P-Slices with out-of-order POC

[blauer]

Hi all,

I have a problem with playing back H.264 files with VLC 0.9.8a. The sequence contains P-Slices not used for reference (nal_ref_idc=0). There are no B-Slices present, but POCs of the P-Slices can be out of order.

It seems that the reordering of frames is not done correctly, see
http://home.arcor.de/wg.list/seq/fire.264 (1.8 MB)
The display order of some frames is broken.

However, if you put the same sequence into an mp4-container
http://home.arcor.de/wg.list/seq/fire.mp4 (1.8 MB)
VLC decodes the sequence without errors.

The ffplay sample application from ffmpeg also decodes the original h.264 file without display errors.

I did some debugging with the two different demuxers involved (modules/demux/mp4/mp4.c for the mp4-file and modules/demux/avformat/demux.c for the h.264 raw stream). It seems that PTS/DTS timing generation gets somehow wrong with the 264-file "demuxer".

However, I cannot find the part of the code that causes this problem. Does anybody know what is the problem here?

Thanks,
Kurt

[Jean-Baptiste Kempf]

ARe you sure this isn't the same issue than http://trac.videolan.org/vlc/ticket/1450 ?

[blauer]

Hi,

I just did some quick analysis of the sample stream linked to ticket 1450
http://www.mediafire.com/?7royf3j3yzc.

It basically shows the same error: the display order is corrupt, but plays fine when the same stream is embedded in an mp4 container.

However, the streams are totally different:

Stream from ticket 1450 has:
- B-Slices
- SEI timing
- reference picture list reordering
- main profile

My stream http://home.arcor.de/wg.list/seq/fire.264 has:
- only P-Slices
- no SEI timing information
- no reference picture list reordering
- baseline profile

Maybe this information is useful for someone working on that ticket.

[Jean-Baptiste Kempf]

Create new ticket or append this information to this thread.