title: ffmpeg converting multiple audio formats to mp3
body: <p>I was wondering how can I convert multiple audio formats, i.e. wav, aac, m4a to mp3 at once with ffmpeg and php (not ffmpeg-php)?</p>
  
  <p>So if this:</p>
  
  <p><code>ffmpeg -i son_origine.avi -vn -ar 44100 -ac 2 -ab 192 -f mp3 son_final.mp3</code></p>
  
  <p>Converts wav to mp3, how can I add multiple extensions in there?</p>