title: FFMPEG: How to move the video without stretching it?
body: <p>Please, I need help with the following ...</p>
  
  <p>I want to move a video (portrait type), but without stretching it ...
  To create a 16: 9 video, with FFMPEG ...
  I have the following example ...</p>
  
  <p><code>ffmpeg -i video.mpg -filter:v "crop=in_w-100:in_h-100:0:(in_h-out_h)/2 +((in_h-out_h)/2)*sin(t)" -y out.mp4</code></p>
  
  <p><img src="https://i.stack.imgur.com/aDGLA.png" alt="Example conceptual image"></p>