Remuxing vorbis into AVI leads to very large files

[Clément Bœsch]

Create a small OGG/Vorbis file:

☭ ./ffmpeg -f lavfi -i sine -c:a libvorbis -t 100 out.ogg
ffmpeg version N-66293-g5ddfac8 Copyright (c) 2000-2014 the FFmpeg developers
  built on Sep 16 2014 14:01:03 with gcc 4.9.1 (GCC)
  configuration: --enable-gpl --enable-libfribidi --enable-fontconfig --enable-libfreetype --enable-libx264 --enable-libvorbis --enable-libmp3lame --enable-libmodplug --enable-libass --assert-level=2 --samples=/home/ux/fate-samples --cc='ccache cc'
  libavutil      54.  7.100 / 54.  7.100
  libavcodec     56.  1.100 / 56.  1.100
  libavformat    56.  4.101 / 56.  4.101
  libavdevice    56.  0.100 / 56.  0.100
  libavfilter     5.  1.100 /  5.  1.100
  libswscale      3.  0.100 /  3.  0.100
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  0.100 / 53.  0.100
Input #0, lavfi, from 'sine':
  Duration: N/A, start: 0.000000, bitrate: 705 kb/s
    Stream #0:0: Audio: pcm_s16le, 44100 Hz, mono, s16, 705 kb/s
Output #0, ogg, to 'out.ogg':
  Metadata:
    encoder         : Lavf56.4.101
    Stream #0:0: Audio: vorbis (libvorbis), 44100 Hz, mono, fltp
    Metadata:
      encoder         : Lavc56.1.100 libvorbis
Stream mapping:
  Stream #0:0 -> #0:0 (pcm_s16le (native) -> vorbis (libvorbis))
Press [q] to stop, [?] for help
size=     170kB time=00:01:40.00 bitrate=  14.0kbits/s    
video:0kB audio:160kB subtitle:0kB other streams:0kB global headers:3kB muxing overhead: 6.276714%

Remux it to AVI:

☭ ./ffmpeg -i out.ogg -c copy out.avi
ffmpeg version N-66293-g5ddfac8 Copyright (c) 2000-2014 the FFmpeg developers
  built on Sep 16 2014 14:01:03 with gcc 4.9.1 (GCC)
  configuration: --enable-gpl --enable-libfribidi --enable-fontconfig --enable-libfreetype --enable-libx264 --enable-libvorbis --enable-libmp3lame --enable-libmodplug --enable-libass --assert-level=2 --samples=/home/ux/fate-samples --cc='ccache cc'
  libavutil      54.  7.100 / 54.  7.100
  libavcodec     56.  1.100 / 56.  1.100
  libavformat    56.  4.101 / 56.  4.101
  libavdevice    56.  0.100 / 56.  0.100
  libavfilter     5.  1.100 /  5.  1.100
  libswscale      3.  0.100 /  3.  0.100
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  0.100 / 53.  0.100
Input #0, ogg, from 'out.ogg':
  Duration: 00:01:40.00, start: 0.000000, bitrate: 13 kb/s
    Stream #0:0: Audio: vorbis, 44100 Hz, mono, fltp, 80 kb/s
    Metadata:
      ENCODER         : Lavc56.1.100 libvorbis
Output #0, avi, to 'out.avi':
  Metadata:
    ISFT            : Lavf56.4.101
    Stream #0:0: Audio: vorbis (oV[0][0] / 0x566F), 44100 Hz, mono, 80 kb/s
    Metadata:
      ENCODER         : Lavc56.1.100 libvorbis
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
Press [q] to stop, [?] for help
size=   23610kB time=00:01:39.99 bitrate=1934.2kbits/s    
video:0kB audio:160kB subtitle:0kB other streams:0kB global headers:3kB muxing overhead: 14616.299805%

Compare sizes:

☭ ls -l out.{ogg,avi}
-rw-r--r-- 1 ux ux  24M Sep 16 14:04 out.avi
-rw-r--r-- 1 ux ux 171K Sep 16 14:01 out.ogg

out.avi seems to play fine. I don't know if it's a regression.

[Carl Eugen Hoyos]

Is this issue only reproducible with libvorbis or also with the native vorbis encoder?

This is indeed a regression but the older (smaller) files were unplayable with vlc.

[Clément Bœsch]

Replying to cehoyos:

Is this issue only reproducible with libvorbis or also with the native vorbis encoder?

The source encoder doesn't matter. You can use ./ffmpeg -f lavfi -i sine -c:a vorbis -strict -2 -ac 2 -t 100 out.ogg, the issue will be that same.

This is indeed a regression but the older (smaller) files were unplayable with vlc.

Were you able to point out the regression commit?

[Carl Eugen Hoyos]

The behaviour changed in 15c6be8c / 5602a464

[Timothy Gu]

Probably related to #1690.

[Timothy Gu]

Does remuxing to other formats (eg matroska) show this problem?

[Clément Bœsch]

Replying to Timothy_Gu:

Does remuxing to other formats (eg matroska) show this problem?

No

[compn]

do not put vorbis in avi. we should fail if user wants to do that.

[Michael Niedermayer]

Is there any evidence that what ffmpeg does is incorrect ?
what would you expect or rather which tool generates functional vorbis in avi that is not huge?