ffmpeg wmv to flv encoding produces segmentation fault

[heinzkeinz]

Hi there,

when I try to en code a wmv file to flv with ffmpeg I get reproducible segmentation faults:
The file I use is a file which comes with Windows Media Encoder 9:
C:\Program Files\Windows Media Components\Encoder\intermission.wmv

This happens on Karmic
2.6.31-19-server #56-Ubuntu SMP Thu Jan 28 03:40:48 UTC 2010 x86_64 GNU/Linux

command:
 `which ffmpeg` -i "/home/heinz/videos/intermission.8287176493597819.wmv" -b 400k -f flv -acodec libmp3lame -ar 22050 -ab 64k -ac 2 -async 4 -s 320x240 "/home/heinz/videos//intermission.8287176493597819.flv"

FFmpeg version SVN-r19352-4:0.5+svn20090706-2ubuntu2, Copyright (c) 2000-2009 Fabrice Bellard, et al.
  configuration: --extra-version=4:0.5+svn20090706-2ubuntu2 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --disable-stripping --disable-vhook --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --extra-cflags=-I/build/buildd/ffmpeg-0.5+svn20090706/debian/include --enable-shared --disable-static
  libavutil 49.15. 0 / 49.15. 0
  libavcodec 52.20. 0 / 52.20. 0
  libavformat 52.31. 0 / 52.31. 0
  libavdevice 52. 1. 0 / 52. 1. 0
  libavfilter 0. 4. 0 / 0. 4. 0
  libswscale 0. 7. 1 / 0. 7. 1
  libpostproc 51. 2. 0 / 51. 2. 0
  built on Oct 13 2009 22:35:00, gcc: 4.4.1

Seems stream 1 codec frame rate differs from container frame rate: 1000.00 (1000/1) -> 30.00 (30/1)
Input #0, asf, from '/home/heinz/videos/intermission.8287176493597819.wmv':
  Duration: 00:00:39.94, start: 20.000000, bitrate: 229 kb/s
    Stream #0.0: Audio: wmav2, 48000 Hz, stereo, s16, 64 kb/s
    Stream #0.1: Video: wmv3, yuv420p, 320x240, 300 kb/s, 30 tbr, 1k tbn, 1k tbc
Output #0, flv, to '/home/heinz/videos/intermission.8387767988976978.flv':
    Stream #0.0: Video: flv, yuv420p, 320x240, q=2-31, 400 kb/s, 90k tbn, 30 tbc
    Stream #0.1: Audio: libmp3lame, 22050 Hz, stereo, s16, 64 kb/s
Stream mapping:
  Stream #0.1 -> #0.0
  Stream #0.0 -> #0.1
Press [q] to stop encoding
Segmentation fault
[swscaler @ 0x1d28d60]No accelerated colorspace conversion found.
[swscaler @ 0x24d0d60]No accelerated colorspace conversion found.

dmesg says:
[941811.816492] ffmpeg[31511]: segfault at 7fe01c78bf20 ip 00007fe01c1377f6 sp 00007fff65cdcd08 error 7 in libavcodec.so.52.20.0[7fe01c056000+530000]

The same happens on Jaunty:
2.6.28-18-server #59-Ubuntu SMP Thu Jan 28 02:25:03 UTC 2010 x86_64 GNU/Linux

command:
`which ffmpeg` -i "/home/heinz/intermission.wmv" -b 400k -f flv -acodec libmp3lame -ar 22050 -ab 64k -ac 2 -async 4 -s 320x240 "/home/heinz/intermission.wmv"

FFmpeg version 0.5-svn17737+3:0.svn20090303-1ubuntu6, Copyright (c) 2000-2009 Fabrice Bellard, et al.
  configuration: --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --extra-version=svn17737+3:0.svn20090303-1ubuntu6 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --disable-stripping --disable-vhook --enable-libdc1394 --enable-shared --disable-static
  libavutil 49.15. 0 / 49.15. 0
  libavcodec 52.20. 0 / 52.20. 0
  libavformat 52.31. 0 / 52.31. 0
  libavdevice 52. 1. 0 / 52. 1. 0
  libavfilter 0. 4. 0 / 0. 4. 0
  libswscale 0. 7. 1 / 0. 7. 1
  libpostproc 51. 2. 0 / 51. 2. 0
  built on Apr 10 2009 23:20:33, gcc: 4.3.3

Seems stream 1 codec frame rate differs from container frame rate: 1000.00 (1000/1) -> 30.00 (30/1)
Input #0, asf, from '/home/robert/intermission.wmv':
  Duration: 00:00:39.94, start: 20.000000, bitrate: 229 kb/s
    Stream #0.0: Audio: wmav2, 48000 Hz, stereo, s16, 64 kb/s
    Stream #0.1: Video: wmv3, yuv420p, 320x240, 300 kb/s, 30 tbr, 1k tbn, 1k tbc
Output #0, flv, to 'intermission.flv':
    Stream #0.0: Video: flv, yuv420p, 320x240, q=2-31, 400 kb/s, 90k tbn, 30 tbc
    Stream #0.1: Audio: libmp3lame, 22050 Hz, stereo, s16, 64 kb/s
Stream mapping:
  Stream #0.1 -> #0.0
  Stream #0.0 -> #0.1
Press [q] to stop encoding
Segmentation fault2 q=2.0 size= 0kB time=16.53 bitrate= 0.1kbits/s

dmesg says:

[1154416.757786] ffmpeg[26557]: segfault at 7f277e555020 ip 00007f277df45cf7 sp 00007fff3e7d5ca8 error 7 in libavcodec.so.52.20.0[7f277debb000+494000]

Any Ideas?

Salu2

Heinz

[Reinhard Tartler (siretart)]

TBH, I supect that this particular wmv file uses a non-implemented
colorspace. Does this also occur with ffmpeg trunk?

also, can you please attach the sample to this bug? If it doesn't occur
with trunk, it could be useful for bisecting the change that fixes this
segfault.

[llogan (loul)]

This does not occur in FFmpeg SVN for me, but using the above command I get a seg fault on a wmv2 and a wmv3 file. This seems to occur when -async is >= 2 in Karmic. The seg fault did not give the swscaler error. Changing the output format did not prevent a seg fault. There was no seg fault using two other input formats: DV and H.264.

[Reinhard Tartler (siretart)]

in this case this report needs forwarding upstream. See http://ffmpeg.org/bugreports.html for instructions how to do that

[Reinhard Tartler (siretart)]

setting to incomplete as the bug does not have a sample file attached

[heinzkeinz (heinzkeinz)]

Hi I attach this wmv file.
It is one that comes with Microsoft Windows Media Encoder 9, so it should be rather a standard one

[heinzkeinz (heinzkeinz)]

@LouL
__________________
You are right. using async > 2 does not give segmentation faults, neither in Jaunty, nor in Karmic, this workaround should work for me, thanks

@Reinhard Tartler
__________________
I use the "default" installation
in Karmic:
ffmpeg 4:0.5+svn20090706-2ubuntu2
libavcodec-extra-52 4:0.5+svn20090706-2ubuntu3
ubuntu-restricted-extras 36

and Jaunty:
ffmpeg 3:0.svn20090303-1ubuntu6
libavcodec-unstripped-52 3:0.svn20090303-1ubuntu2+unstripped1
ubuntu-restricted-extras 31

I would have to compile ffmpeg trunk on both to test, but as these are production servers I don't really dare.
The problems seems to be libavcodec, no?
If I find some time this afternoon I 'll compile trunk on clean Karmic, if it encoding produces segfault I'll report upstream bug.
In any case I'll let you know.

[Reinhard Tartler (siretart)]

with the provided sample I was able to reproduce the crash with ffmpeg 0.5.1. See the attached stack trace.

[Reinhard Tartler (siretart)]

this does not occur in ffmpeg trunk, only in 0.5.1

[heinzkeinz (heinzkeinz)]

@Reinhard Tartler
_______________________
No segmentation fault on ffmpeg trunk as of today Mar 2 2010
built on clean Karmic install

Hope this info is useful,
if you need any further info let me know ..

`which ffmpeg` -i "intermission.wmv" -b 400k -f flv -acodec libmp3lame -ar 22050 -ab 64k -ac 2 -async 4 -s 320x240 "intermission.flv"
FFmpeg version SVN-r22144, Copyright (c) 2000-2010 the FFmpeg developers
  built on Mar 2 2010 13:44:04 with gcc 4.4.1
  configuration: --enable-gpl --enable-version3 --enable-nonfree --enable-postproc --enable-pthreads --enable-libfaac --enable-libfaad --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libx264 --enable-libxvid --enable-x11grab
  libavutil 50. 9. 0 / 50. 9. 0
  libavcodec 52.55. 0 / 52.55. 0
  libavformat 52.54. 0 / 52.54. 0
  libavdevice 52. 2. 0 / 52. 2. 0
  libswscale 0.10. 0 / 0.10. 0
  libpostproc 51. 2. 0 / 51. 2. 0

Seems stream 1 codec frame rate differs from container frame rate: 1000.00 (1000/1) -> 30.00 (30/1)
Input #0, asf, from 'intermission.wmv':
  Metadata:
    WMFSDKVersion : 9.00.00.2925
    WMFSDKNeeded : 0.0.0.0000
    IsVBR : 0
  Duration: 00:00:39.99, start: 20.000000, bitrate: 229 kb/s
    Stream #0.0(eng): Audio: wmav2, 48000 Hz, 2 channels, s16, 64 kb/s
    Stream #0.1(eng): Video: wmv3, yuv420p, 320x240, 300 kb/s, 30 tbr, 1k tbn, 1k tbc
Output #0, flv, to 'intermission.flv':
  Metadata:
    encoder : Lavf52.54.0
    Stream #0.0(eng): Video: flv, yuv420p, 320x240, q=2-31, 400 kb/s, 1k tbn, 30 tbc
    Stream #0.1(eng): Audio: libmp3lame, 22050 Hz, 2 channels, s16, 64 kb/s
Stream mapping:
  Stream #0.1 -> #0.0
  Stream #0.0 -> #0.1
Press [q] to stop encoding
frame= 1199 fps=1044 q=2.0 Lsize= 1574kB time=40.00 bitrate= 322.4kbits/s
video:1217kB audio:314kB global headers:0kB muxing overhead 2.812108%

[Launchpad Janitor (janitor)]

This bug was fixed in the package ffmpeg - 4:0.6~svn20100505-1ubuntu1

---------------
ffmpeg (4:0.6~svn20100505-1ubuntu1) maverick; urgency=low

  * merge from debian/experimental. remaining changes:
    - don't disable encoders
    - don't build against libfaad, libdirac and libopenjpeg (all in universe)

ffmpeg (4:0.6~svn20100505-1) experimental; urgency=low

  * update to new upstream. Closes: #569727
    - fixes various segfaults and other minor feature improvements
      Closes: #374931, #522449, #501891, #559712, #420231, #369127, #538082,
              #298095, #294422, #561553, #525385, #495274, #420230
      LP: #305286, #457106, #529200, #301723, #305315, #336479, #420230,
          #412063, #428912, #432181, #440591, #453732, #453732, #453732,
      #514259, #515243, #521472, #530186, #530186, #197842, #483317,
     #483317, #539407, #280098, #331255, #566107, #569823, #570305,
     #573190
  * Fixup lintian overrides for new upstream snapshot
  * Bump Standards-Version to 3.8.4
  * Many upstream changes, see upstream Changelog for details
 -- Reinhard Tartler <email address hidden> Wed, 26 May 2010 00:01:17 +0200