title: How to change video speed only while adding a same-speed separated audio stream with ffmpeg?
body: <p>I'm using ffmpeg for video filter.</p>
  
  <p>But, When I changed video speed, that time I got issue</p>
  
  <ul>
  <li><p><strong>Audio is longer than video</strong> : </p>
  
  <pre><code>ffmpeg -i INPUT.mp4  -filter:v setpts=0.5*PTS -shortest -y -preset ultrafast OUTPUT.mp4
  </code></pre></li>
  </ul>
  
  <p>I want to set audio's length same as video's length. </p>
  
  <ul>
  <li><strong>shortest</strong> =   to extend audio streams to the same length as the video stream</li>
  </ul>
  
  <p>In my case, <code>shortest</code> is not working. Video file and audio file, both are different and then after merging in a video file. Video's last frame stop and audio is continued working.</p>