Opened 5 years ago

Last modified 3 years ago

#2507 open defect

Unknown packet pts values in mpeg4-ogg sample

Reported by: cehoyos Owned by:
Priority: normal Component: undetermined
Version: git-master Keywords: ogg asp videolan
Cc: cus@passwd.hu Blocked By:
Blocking: Reproduced by developer: yes
Analyzed by developer: no

Description (last modified by cehoyos)

(Sample from videolan ticket 8486)
A vlc user provided a sample that plays fine with MPlayer (and totem), can be transcoded with ffmpeg (see ticket #2506), but plays with heavy A/V desync with ffplay since d148339
With older ffplay versions, many frames are dropped (but the sample plays mostly in-sync).

$ ffplay File\ 50MB\ DG\ Split\ 206\ Video\ Issue.ogm
ffplay version N-52542-g5149407 Copyright (c) 2003-2013 the FFmpeg developers
  built on Apr 28 2013 14:19:06 with gcc 4.7 (SUSE Linux)
  configuration: --enable-gpl --disable-indev=jack
  libavutil      52. 27.101 / 52. 27.101
  libavcodec     55.  6.100 / 55.  6.100
  libavformat    55.  3.100 / 55.  3.100
  libavdevice    55.  0.100 / 55.  0.100
  libavfilter     3. 61.101 /  3. 61.101
  libswscale      2.  2.100 /  2.  2.100
  libswresample   0. 17.102 /  0. 17.102
  libpostproc    52.  3.100 / 52.  3.100
Input #0, ogg, from 'File 50MB DG Split 206 Video Issue.ogm':=0/0
  Duration: 00:04:41.11, start: 0.000000, bitrate: 1492 kb/s
    Stream #0:0: Video: mpeg4 (XVID / 0x44495658), yuv420p, 576x432, 23.98 fps, 23.98 tbr, 23.98 tbn, 23.98 tbc
    Stream #0:1(English): Audio: vorbis, 48000 Hz, stereo, fltp, 89 kb/s
    Stream #0:2(Japanese): Audio: vorbis, 48000 Hz, stereo, fltp, 89 kb/s
    Stream #0:3(English): Subtitle: text
  48.34 A-V: 23.441 fd=  32 aq= 1348KB vq=14012KB sq=    0B f=0/144

Change History (12)

comment:1 Changed 5 years ago by cehoyos

  • Description modified (diff)

comment:3 Changed 4 years ago by cus

  • Component changed from undetermined to FFplay
  • Owner set to cus
  • Status changed from new to open

comment:4 Changed 4 years ago by cehoyos

  • Keywords asp added; mpeg4 removed

comment:5 Changed 4 years ago by cus

  • Cc cus@passwd.hu added
  • Component changed from FFplay to undetermined
  • Keywords regression removed
  • Owner cus deleted
  • Summary changed from Heavy desync with ffplay for a mpeg4-ogg sample to Invalid pts values in mpeg4-ogg sample

FFplay part is fixed in 28031404571bb69a1d685341cfc1cd737ecb9681.

However there seems to be a avformat/avcodec issue here as well, which makes the PTS values bad.

comment:6 Changed 4 years ago by cus

  • Reproduced by developer set
  • Summary changed from Invalid pts values in mpeg4-ogg sample to Unknown packet pts values in mpeg4-ogg sample

Actually the PTS values are only missing, they are not invalid. And not only the decoded frame pts-es, but the packet pts values as well. However you have to decode the video, to experience the problem, ffprobe -show_packets does not show any issues, but ffprobe -show_packets -show_frames does.

comment:7 Changed 3 years ago by michael

cannot reproduce missing timestamps, but maybe iam looking at the wrong place or time

also if its not a regression anymore then priority should probably be reduced to normal

comment:8 Changed 3 years ago by cus

ffplay -vf showinfo will eventually show you frames with NOPTS pts-es.

comment:9 Changed 3 years ago by cus

  • Priority changed from important to normal

Regression part was in ffplay, and that is fixed, so reducing priority to normal.

comment:10 Changed 3 years ago by michael

"-fflags +genpts" can be used to get pts for these frames.
is there evidence that the file contains pts values at the ogg level ?

comment:11 Changed 3 years ago by cehoyos

Playback looks nicer with totem imo than with ffplay.

comment:12 Changed 3 years ago by cehoyos

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