Bug#797965: BS1770GAIN

Christoph Anton Mitterer calestyo at scientia.net
Fri Sep 4 21:02:17 UTC 2015

Peter (=upstream) has asked me off list to check whether:
$ ffmpeg -i in.mp3 -acodec copy -y out.mp3
also makes the resulting files having gaps.
The back story is that bs1770gain apparently somehow uses ffmpeg.

And the answer is yes, after copying the files as above with ffmpeg,
they have gaps when played back.

So apart from the fact that I wonder why ffmpeg is used here at all
(shouldn't just some ID3 tags or that like be written?), it may be an
issue in ffmpeg.

btw: Using ffmpeg, even in copy mode seems to have other issues as
ffmpeg version 2.7.2-2+b1 Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 5.2.1 (Debian 5.2.1-15) 20150808
  configuration: --prefix=/usr --extra-version=2+b1 --build-suffix=-ffmpeg --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --enable-shared --disable-stripping --enable-avresample --enable-avisynth --enable-frei0r --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libopenjpeg --enable-openal --enable-libopus --enable-libpulse --enable-librtmp --enable-libschroedinger --enable-libshine --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libxvid --enable-libzvbi --enable-opengl --enable-x11grab --enable-libdc1394 --enable-libiec61883 --enable-libzmq --enable-libssh --enable-libx264 --enable-libopencv --enable-libx265
  WARNING: library configuration mismatch
  avcodec     configuration: --prefix=/usr --extra-version=2+b1 --build-suffix=-ffmpeg --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --enable-shared --disable-stripping --enable-avresample --enable-avisynth --enable-frei0r --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libopenjpeg --enable-openal --enable-libopus --enable-libpulse --enable-librtmp --enable-libschroedinger --enable-libshine --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libxvid --enable-libzvbi --enable-opengl --enable-x11grab --enable-libdc1394 --enable-libiec61883 --enable-libzmq --enable-libssh --enable-libx264 --enable-libopencv --enable-libx265 --enable-version3 --disable-doc --disable-programs --disable-avdevice --disable-avfilter --disable-avformat --disable-avresample --disable-postproc --disable-swscale --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libvo_aacenc --enable-libvo_amrwbenc
  libavutil      54. 27.100 / 54. 27.100
  libavcodec     56. 41.100 / 56. 41.100
  libavformat    56. 36.100 / 56. 36.100
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 16.101 /  5. 16.101
  libavresample   2.  1.  0 /  2.  1.  0
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  2.100 /  1.  2.100
  libpostproc    53.  3.100 / 53.  3.100
[mp3 @ 0x15a8e40] Skipping 0 bytes of junk at 417.
Input #0, mp3, from '2.mp3':
  Duration: 00:10:45.09, start: 0.025057, bitrate: 166 kb/s
    Stream #0:0: Audio: mp3, 44100 Hz, stereo, s16p, 166 kb/s
      encoder         : LAME3.99r
Output #0, mp3, to 'b.mp3':
    TSSE            : Lavf56.36.100
    Stream #0:0: Audio: mp3, 44100 Hz, stereo, 166 kb/s
      encoder         : LAME3.99r
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
Press [q] to stop, [?] for help
[mp3 @ 0x15abba0] Audio packet of size 128 (starting with 54414700...) is invalid, writing it anyway.
size=   13141kB time=00:10:45.09 bitrate= 166.9kbits/s    
video:0kB audio:13140kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.003872%

As one can see above here, there's an error that ffmpeg thinks
something would be invalid.
It seems to still write it here, but I'd guess that the copy mode is
still like a full parsing and freshly rewriting.
Sounds like an invitation for all kinds of things going wrong :-(

@Peter: Why exactly do you need to use ffmpeg for writing? Shouldn't it
be enough to write some tags?

-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/x-pkcs7-signature
Size: 5313 bytes
Desc: not available
URL: <http://lists.alioth.debian.org/pipermail/pkg-multimedia-maintainers/attachments/20150904/b7c136fd/attachment.bin>

More information about the pkg-multimedia-maintainers mailing list