title: v4l2-ctl - Video length and stream count
body: <p>I am trying to record a 15 seconds video using v4l2-ctl but I got a bit confused with its parameters, even after looking for articles on the Internet.</p>
  
  <pre><code>v4l2-ctl --set-fmt-video=width=960,height=720,pixelformat=1
  v4l2-ctl --stream-mmap=3 --stream-count=100 --stream-to=$1
  </code></pre>
  
  <p>How do I set the video length?
  What exactly does the <code>--stream-count</code> mean?</p>