title: Asking ffmpeg to extract frames at the original frame rate
body: <p>On the FFmpeg documentation (<a href="http://linux.die.net/man/1/ffmpeg" rel="nofollow noreferrer">here</a>, and <a href="http://ffmpeg.org/ffmpeg.html#SEC9" rel="nofollow noreferrer">here</a>) I read that, by default, <code>FFmpeg</code> chooses to extract frames at 25 frames per second (otherwise you can specify a framerate with the <code>-r</code> option)</p>
  
  <p>My problem is that I have a folder with dozens of videos, each of them recorded at different frame rates, so my question is:</p>
  
  <p>Is there a way to ask <code>FFmpeg</code> to extract frames from a video at the <strong>"native"</strong> frame rate (i.e. the original frame rate at which the video was recorded)?</p>
  
  <p>In case it matters, I am working with <code>MP4</code> files</p>