[branden@localhost dwhelper]$ ffprobe -i FRC_2012_game.mp4 -acodec libvorbis -ab 64k -vcodec libx264 -crf 18 -preset veryslow -profile high FRC_2012_game.mkv
ffprobe version git-2012-01-09-741aca7 Copyright (c) 2007-2012 the FFmpeg developers
  built on Jan  8 2012 16:56:15 with gcc 4.6.2 20111125 (prerelease)
  configuration: --prefix=/usr --enable-gpl --enable-libfaac --enable-libmp3lame --enable-libtheora --enable-libvorbis --enable-libx264 --enable-nonfree --enable-postproc --enable-x11grab
  libavutil      51. 34.100 / 51. 34.100
  libavcodec     53. 54.100 / 53. 54.100
  libavformat    53. 29.100 / 53. 29.100
  libavdevice    53.  4.100 / 53.  4.100
  libavfilter     2. 58.100 /  2. 58.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0.  6.100 /  0.  6.100
  libpostproc    51.  2.100 / 51.  2.100
Unrecognized option 'acodec'
Failed to set value 'libvorbis' for option 'acodec'
[branden@localhost dwhelper]$