Opened 11 years ago

Closed 11 years ago

Last modified 11 years ago

#2618 closed defect (fixed)

MPNG used to work better

Reported by: Carl Eugen Hoyos Owned by:
Priority: normal Component: avcodec
Version: git-master Keywords: png regression
Cc: Blocked By:
Blocking: Reproduced by developer: yes
Analyzed by developer: no

Description

http://samples.ffmpeg.org/PNG-seq/mpng.avi used to play with ffplay with minor artefacts, is completely broken since ee30cda

$ ffmpeg -i mpng.avi out.avi
ffmpeg version N-53721-gf70d021 Copyright (c) 2000-2013 the FFmpeg developers
  built on May 31 2013 21:12:24 with gcc 4.7 (SUSE Linux)
  configuration: --enable-gpl --disable-indev=jack
  libavutil      52. 34.100 / 52. 34.100
  libavcodec     55. 12.102 / 55. 12.102
  libavformat    55.  8.102 / 55.  8.102
  libavdevice    55.  2.100 / 55.  2.100
  libavfilter     3. 73.100 /  3. 73.100
  libswscale      2.  3.100 /  2.  3.100
  libswresample   0. 17.102 /  0. 17.102
  libpostproc    52.  3.100 / 52.  3.100
Input #0, avi, from 'mpng.avi':
  Duration: 00:00:04.00, start: 0.000000, bitrate: 8987 kb/s
    Stream #0:0: Video: png (MPNG / 0x474E504D), rgba, 160x120 [SAR 2834:2834 DAR 4:3], 40 tbr, 40 tbn, 40 tbc
[mpeg4 @ 0x22f8ba0] too many threads/slices (9), reducing to 8
Output #0, avi, to 'out.avi':
  Metadata:
    ISFT            : Lavf55.8.102
    Stream #0:0: Video: mpeg4 (FMP4 / 0x34504D46), yuv420p, 160x120 [SAR 1:1 DAR 4:3], q=2-31, 200 kb/s, 40 tbn, 40 tbc
Stream mapping:
  Stream #0:0 -> #0:0 (png -> mpeg4)
Press [q] to stop, [?] for help
Input stream #0:0 frame changed from size:160x120 fmt:rgba to size:160x120 fmt:rgb24
Input stream #0:0 frame changed from size:160x120 fmt:rgb24 to size:160x120 fmt:pal8
Input stream #0:0 frame changed from size:160x120 fmt:pal8 to size:160x120 fmt:gray
frame=  160 fps=0.0 q=31.0 Lsize=     432kB time=00:00:04.00 bitrate= 885.1kbits/s
video:423kB audio:0kB subtitle:0 global headers:0kB muxing overhead 2.234574%

Attachments (2)

wait_for_keyframes_to_enable_p-frames_in_png_ee30cda.patch (1.2 KB ) - added by Thilo Borgmann 11 years ago.
Patch for the old revision where the bug was introduced.
wait_for_keyframes_to_enable_p-frames_in_png_fca435f.patch (1.0 KB ) - added by Thilo Borgmann 11 years ago.
Patch for todays revision that does not fix it anymore.

Download all attachments as: .zip

Change History (7)

comment:1 by llogan, 11 years ago

Reproduced by developer: set
Status: newopen

by Thilo Borgmann, 11 years ago

Patch for the old revision where the bug was introduced.

by Thilo Borgmann, 11 years ago

Patch for todays revision that does not fix it anymore.

comment:2 by Thilo Borgmann, 11 years ago

Two patches uploaded:

For the historic revision "ee30cda", waiting for a keyframe flag before handling P-frames fixes this issue.
(tested with: http://samples.mplayerhq.hu/V-codecs/PNG1/corepng.avi)
(tested with: http://samples.ffmpeg.org/PNG-seq/mpng.avi)

For todays todays revision "fca435f", this does not work anymore because the keyframe flag seems to be handled differently. I don't know how to fix the demuxer(?) or even if it is a demuxer mishandling of the keyframe flag or just a broken file with wrong/missing keyframe flags.

Last edited 11 years ago by Thilo Borgmann (previous) (diff)

comment:3 by Carl Eugen Hoyos, 11 years ago

Summary: MPNG used to work betterMPNG shows artefacts

Michael has pushed a different fix, since artefacts are visible (as before ee30cda) I am leaving this ticket open.

comment:4 by Michael Niedermayer, 11 years ago

Resolution: fixed
Status: openclosed

The regresion has been fixed, please open a seperate ticket for the issues that existed before ee30cda
(it costs time to read through tickets to find out what new issue they are used for at the bottom)

comment:5 by Michael Niedermayer, 11 years ago

Summary: MPNG shows artefactsMPNG used to work better

Thats even more true when the ticket is marked as regression while what remains is not one.
And changing all keywords and flags to match a new issue would be quite wrong too
Also changing the title back so it matches the original issue

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