mmf: 2ch audio encoded with adpcm_yamaha is identified as 1ch

[ami_stuff]

C:\>ffmpeg -i in_22.wav out.mmf
ffmpeg version N-38622-g1eabd71 Copyright (c) 2000-2012 the FFmpeg developers
  built on Mar  7 2012 00:18:03 with gcc 4.6.2
  configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-ru
ntime-cpudetect --enable-avisynth --enable-bzlib --enable-frei0r --enable-libope
ncore-amrnb --enable-libopencore-amrwb --enable-libfreetype --enable-libgsm --en
able-libmp3lame --enable-libopenjpeg --enable-librtmp --enable-libschroedinger -
-enable-libspeex --enable-libtheora --enable-libvo-aacenc --enable-libvo-amrwben
c --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-
libxvid --enable-zlib
  libavutil      51. 42.100 / 51. 42.100
  libavcodec     54. 10.100 / 54. 10.100
  libavformat    54.  2.100 / 54.  2.100
  libavdevice    53.  4.100 / 53.  4.100
  libavfilter     2. 63.100 /  2. 63.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0.  7.100 /  0.  7.100
  libpostproc    52.  0.100 / 52.  0.100
Input #0, wav, from 'in_22.wav':
  Duration: 00:00:01.01, bitrate: 705 kb/s
    Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 22050 Hz, 2 channels,
 s16, 705 kb/s
File 'out.mmf' already exists. Overwrite ? [y/N] y
Output #0, mmf, to 'out.mmf':
  Metadata:
    encoder         : Lavf54.2.100
    Stream #0:0: Audio: adpcm_yamaha, 22050 Hz, 2 channels, s16, 176 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (pcm_s16le -> adpcm_yamaha)
Press [q] to stop, [?] for help
size=      22kB time=00:00:01.02 bitrate= 177.0kbits/s
video:0kB audio:22kB global headers:0kB muxing overhead 0.359553%

C:\>ffmpeg -i out.mmf
ffmpeg version N-38622-g1eabd71 Copyright (c) 2000-2012 the FFmpeg developers
  built on Mar  7 2012 00:18:03 with gcc 4.6.2
  configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-ru
ntime-cpudetect --enable-avisynth --enable-bzlib --enable-frei0r --enable-libope
ncore-amrnb --enable-libopencore-amrwb --enable-libfreetype --enable-libgsm --en
able-libmp3lame --enable-libopenjpeg --enable-librtmp --enable-libschroedinger -
-enable-libspeex --enable-libtheora --enable-libvo-aacenc --enable-libvo-amrwben
c --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-
libxvid --enable-zlib
  libavutil      51. 42.100 / 51. 42.100
  libavcodec     54. 10.100 / 54. 10.100
  libavformat    54.  2.100 / 54.  2.100
  libavdevice    53.  4.100 / 53.  4.100
  libavfilter     2. 63.100 /  2. 63.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0.  7.100 /  0.  7.100
  libpostproc    52.  0.100 / 52.  0.100
[mmf @ 02159BE0] Estimating duration from bitrate, this may be inaccurate
Input #0, mmf, from 'out.mmf':
  Duration: 00:00:02.05, bitrate: 88 kb/s
    Stream #0:0: Audio: adpcm_yamaha, 22050 Hz, 1 channels, s16, 88 kb/s
At least one output file must be specified

[Carl Eugen Hoyos]

Not a regression, decoding works fine if I force stereo, I was unable to find information on the SMAF page if channels > 1 is supported, the code in mmf.c suggests that mono and stereo should work.

[Carl Eugen Hoyos]

Encoding stereo is now an experimental feature (testing mmf / Yamaha SMAF on real hardware would be very welcome!), decoding of files written with FFmpeg should work fine now.