title: ffmpeg how do i know what audio rate to use?
body: <p>Say I have something like this</p>
  
  <pre><code>ffmpeg -i video.avi -ar 22050 -ab 32 -f flv -s 320x240 video.flv 
  
  
  -ar  (Audio sampling rate in Hz)
  -ab  (Audio bit rate in kbit/s)
  </code></pre>
  
  <p>regarding the <code>-ar</code> and the <code>-ab</code> how do I know what rate to use? I got this ffmpeg command from a site somewhere and I was wondering how the person knew what values to put for the rates? Do I need to understand audio in order to figure that out?</p>