Command: system("ffmpeg -i 'one.day.avi'  -ab 64k 'one.day.mp3'")

Output:
ffmpeg version 2.4.3 Copyright (c) 2000-2014 the FFmpeg developers
  built on Nov 17 2014 14:58:28 with Apple LLVM version 6.0 (clang-600.0.54) (based on LLVM 3.5svn)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/2.4.3 --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-nonfree --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-libx264 --enable-libfaac --enable-libmp3lame --enable-libxvid --enable-libfreetype --enable-libtheora --enable-libvorbis --enable-libvpx --enable-librtmp --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libass --enable-ffplay --enable-libspeex --enable-libschroedinger --enable-libfdk-aac --enable-openssl --enable-libopus --enable-libcaca --enable-libquvi --enable-libx265 --enable-libopenjpeg --disable-decoder=jpeg2000 --extra-cflags='-I/usr/local/Cellar/openjpeg/1.5.1_1/include/openjpeg-1.5 ' --enable-vda
  libavutil      54.  7.100 / 54.  7.100
  libavcodec     56.  1.100 / 56.  1.100
  libavformat    56.  4.101 / 56.  4.101
  libavdevice    56.  0.100 / 56.  0.100
  libavfilter     5.  1.100 /  5.  1.100
  libavresample   2.  1.  0 /  2.  1.  0
  libswscale      3.  0.100 /  3.  0.100
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  0.100 / 53.  0.100
Input #0, avi, from '../../../files/movies/chi_hans/one.day/one.day.avi':
  Metadata:
    encoder         : MEncoder UNKNOWN-4.0.1
  Duration: 01:31:59.44, start: 0.000000, bitrate: 535 kb/s
    Stream #0:0: Video: mpeg4 (Simple Profile) (XVID / 0x44495658), yuv420p, 320x240 [SAR 1:1 DAR 4:3], 400 kb/s, 25 fps, 25 tbr, 25 tbn, 25 tbc
    Stream #0:1: Audio: mp3 (U[0][0][0] / 0x0055), 44100 Hz, stereo, s16p, 122 kb/s
Output #0, mp3, to '../../../files/movies/chi_hans/one.day/one.day.mp3':
  Metadata:
    TSSE            : Lavf56.4.101
    Stream #0:0: Audio: mp3 (libmp3lame), 44100 Hz, stereo, s16p, 64 kb/s
    Metadata:
      encoder         : Lavc56.1.100 libmp3lame
Stream mapping:
  Stream #0:1 -> #0:0 (mp3 (native) -> mp3 (libmp3lame))
Press [q] to stop, [?] for help
size=   43121kB time=01:31:59.43 bitrate=  64.0kbits/s
video:0kB audio:43121kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.000571%