[FFmpeg-user] un experimental aac?

[Roger Pack]

I notice that if I convert to ".mp4" today, from 5.1 audio, I get this failure:

$ ffmpeg -i M2U00213.original.mpg  -c:v libx264 -preset fast -qp 0
M2U00213.original.x264.mp4.with_audio.mp4
ffmpeg version 2.5.git Copyright (c) 2000-2015 the FFmpeg developers
  built with Apple LLVM version 6.0 (clang-600.0.56) (based on LLVM 3.5svn)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/HEAD
--enable-shared --enable-pthreads --enable-gpl --enable-version3
--enable-hardcoded-tables --enable-avresample --cc=clang
--host-cflags= --host-ldflags= --enable-libx264 --enable-libmp3lame
--enable-libvo-aacenc --enable-libxvid --enable-vda
  libavutil      54. 20.100 / 54. 20.100
  libavcodec     56. 26.100 / 56. 26.100
  libavformat    56. 25.101 / 56. 25.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 11.102 /  5. 11.102
  libavresample   2.  1.  0 /  2.  1.  0
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  3.100 / 53.  3.100
Input #0, mpeg, from 'M2U00213.original.mpg':
  Duration: 00:01:12.57, start: 0.220133, bitrate: 9005 kb/s
    Stream #0:0[0x80]: Audio: ac3, 48000 Hz, 5.1(side), fltp, 448 kb/s
    Stream #0:1[0x1e0]: Video: mpeg2video (Main), yuv420p(tv), 720x480
[SAR 32:27 DAR 16:9], max. 9100 kb/s, 29.97 fps, 29.97 tbr, 90k tbn,
59.94 tbc
File 'M2U00213.original.x264.mp4.with_audio.mp4' already exists.
Overwrite ? [y/N] y
[libx264 @ 0x7f96f4030a00] using SAR=32/27
[libx264 @ 0x7f96f4030a00] using cpu capabilities: MMX2 SSE2Fast SSSE3
SSE4.2 AVX AVX2 FMA3 LZCNT BMI2
[libx264 @ 0x7f96f4030a00] profile High 4:4:4 Predictive, level 3.0, 4:2:0 8-bit
[libx264 @ 0x7f96f4030a00] 264 - core 142 r2455 021c0dc - H.264/MPEG-4
AVC codec - Copyleft 2003-2014 - http://www.videolan.org/x264.html -
options: cabac=1 ref=2 deblock=1:0:0 analyse=0x1:0x111 me=hex subme=6
psy=0 mixed_ref=1 me_range=16 chroma_me=1 trellis=0 8x8dct=1 cqm=0
deadzone=21,11 fast_pskip=0 chroma_qp_offset=0 threads=12
lookahead_threads=2 sliced_threads=0 nr=0 decimate=1 interlaced=0
bluray_compat=0 constrained_intra=0 bframes=0 weightp=1 keyint=250
keyint_min=25 scenecut=40 intra_refresh=0 rc=cqp mbtree=0 qp=0
[libvo_aacenc @ 0x7f96f4800600] Unable to set encoding parameters

Suggestion:
Somehow tweak libvo_aacenc so it warns "you have too many audio channels!"

Second suggestion:
According to https://trac.ffmpeg.org/wiki/Encode/HighQualityAudio
in terms of quality,
aac > libvo_aacenc

perhaps it should be marked unexperimental and made the default for
mp4 (over libvo_aacenc)?
Cheers!
-roger-