writing MP4 with FLAC5.1 audio fails

[julian]

download the file:
​https://dl.dropboxusercontent.com/u/7221986/flac5ch.mkv

$ ffmpeg -i flac5ch.mkv -vcodec copy -acodec copy out.mp4
ffmpeg version 1.0 Copyright (c) 2000-2012 the FFmpeg developers
  built on Nov  4 2012 20:05:11 with llvm-gcc 4.2.1 (LLVM build 2336.9.00)
  configuration: 
  libavutil      51. 73.101 / 51. 73.101
  libavcodec     54. 59.100 / 54. 59.100
  libavformat    54. 29.104 / 54. 29.104
  libavdevice    54.  2.101 / 54.  2.101
  libavfilter     3. 17.100 /  3. 17.100
  libswscale      2.  1.101 /  2.  1.101
  libswresample   0. 15.100 /  0. 15.100
Input #0, matroska,webm, from 'flac5ch.mkv':
  Metadata:
    ENCODER         : Lavf54.29.104
  Duration: 00:00:05.29, start: 0.000000, bitrate: 3078 kb/s
    Stream #0:0(jpn): Video: h264 (High 10), yuv420p10le, 1920x1080 [SAR 1:1 DAR 16:9], 23.98 fps, 23.98 tbr, 1k tbn, 47.95 tbc (default)
    Metadata:
      title           : [QTS] Gekijouban Macross Frontier ~Sayonara no Tsubasa~_Blu-ray Disc
      LANGUAGE        : jpn
    Stream #0:1(jpn): Audio: flac, 48000 Hz, 5.1(side), s16 (default)
    Metadata:
      title           : Japanese Audio 5.1ch
      LANGUAGE        : jpn
[mp4 @ 0x7fb5e8862200] track 1: could not find tag, codec not currently supported in container
Output #0, mp4, to 'out.mp4':
  Metadata:
    encoder         : Lavf54.29.104
    Stream #0:0(jpn): Video: h264 ([33][0][0][0] / 0x0021), yuv420p10le, 1920x1080 [SAR 1:1 DAR 16:9], q=2-31, 23.98 fps, 1k tbn, 1k tbc (default)
    Metadata:
      title           : [QTS] Gekijouban Macross Frontier ~Sayonara no Tsubasa~_Blu-ray Disc
      LANGUAGE        : jpn
    Stream #0:1(jpn): Audio: flac, 48000 Hz, 5.1(side) (default)
    Metadata:
      title           : Japanese Audio 5.1ch
      LANGUAGE        : jpn
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
  Stream #0:1 -> #0:1 (copy)
Could not write header for output file #0 (incorrect codec parameters ?): Operation not permitted

[Carl Eugen Hoyos]

isom (mp4) does not support flac, this is not a limitation of FFmpeg. Which application would you use for playback of flac-in-mp4?

[julian]

ok sounds alright

the error messages could be somewhat more descriptive though, looks just like a random failure, thats why i filed the bug.

some 5.1 receivers support FLAC5.1 decoding so i guess it could probably work with any player that just forwards it to the optical output...