title: ffmpeg cut first 5 seconds
body: <p>I am having trouble removing the first 5 seconds of a .mp4 video. Here is what I have so far: </p>
  
  <p><code>subprocess.call("ffmpeg -ss 00:00:00 -t 00:00:05 -i /home/requiem/Desktop/t1.mp4 -vcodec copy -acodec copy /home/requiem/Desktop/t2.mp4", shell=True)</code></p>
  
  <p>The issue is that it just takes the first 5 second and saves it, but I want the first 5 seconds removed and the rest saved. How would I do that, or can I find the duration of the video so I can set -ss 00:00:05 and -t DURATION</p>