[Ubuntu-BR] ffmpeg - conversão wmv para mp3

[Salles]

Como não entendo de parâmetros de áudio e vídeo, preciso de uma ajuda de
vocês na conversão de um arquivo wmv para mp3.
Creio que tenho que acrescentar algo a mais na sintaxe mas não sei
determinar o quê, segue o resultado do comando:

nethell em nethell:~$ ffmpeg -i leon.wmv leon.mp3
FFmpeg version 0.5-svn17737+3:0.svn20090303-1ubuntu6, Copyright (c)
2000-2009 Fabrice Bellard, et al.
  configuration: --enable-gpl --enable-postproc --enable-swscale
--enable-x11grab --extra-version=svn17737+3:0.svn20090303-1ubuntu6
--prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-libgsm
--enable-libschroedinger --enable-libspeex --enable-libtheora
--enable-libvorbis --enable-pthreads --disable-stripping --disable-vhook
--enable-libdc1394 --disable-armv5te --disable-armv6 --disable-armv6t2
--disable-armvfp --disable-neon --disable-altivec --disable-vis
--enable-shared --disable-static
  libavutil     49.15. 0 / 49.15. 0
  libavcodec    52.20. 0 / 52.20. 0
  libavformat   52.31. 0 / 52.31. 0
  libavdevice   52. 1. 0 / 52. 1. 0
  libavfilter    0. 4. 0 /  0. 4. 0
  libswscale     0. 7. 1 /  0. 7. 1
  libpostproc   51. 2. 0 / 51. 2. 0
  built on Apr 10 2009 23:18:41, gcc: 4.3.3
[wmv3 @ 0x99c8db0]Extra data: 8 bits left, value: 0
Seems stream 1 codec frame rate differs from container frame rate:
1000.00 (1000/1) -> 29.92 (359/12)
Input #0, asf, from 'leon.wmv':
  Duration: 00:06:37.76, start: 5.000000, bitrate: 114 kb/s
    Stream #0.0: Audio: wmav2, 11025 Hz, mono, s16, 10 kb/s
    Stream #0.1: Video: wmv3, yuv420p, 320x240, 100 kb/s, 29.92 tbr, 1k
tbn, 1k tbc
Output #0, mp3, to 'leon.mp3':
    Stream #0.0: Audio: 0x0000, 11025 Hz, mono, s16, 64 kb/s
Stream mapping:
  Stream #0.0 -> #0.0
Unsupported codec for output stream #0.0
nethell em nethell:~$

Salles (Nethell) Ubuntu User 24389 Linux User 496632