title: Scaling and stacking 2 videos
body: <p>I have 2 inputs and I want to scale, crop and put them on top of each other at the same time. My command should look something like this:</p>
  
  <pre><code>ffmpeg -i input1 -i input2 -filter_complex crop=10000:5000:1000:0,scale=3840:1536 vstack output.mp4
  </code></pre>
  
  <p>I know I need to use chaining (?) but I tried to look it up online and couldn't really get it to work.</p>
  
  <p>So what would be the correct syntax the scale and crop both inputs and then put them vertically on top of each other while using '-filter_complex' only once?</p>