title: How to improve People Occlusion in ARKit 3.0
body: <p>We are working on a demo app using people's occlusion in ARKit. Because we want to add videos in the final scene, we use <code>SCNPlane</code>s to render the video using a <code>SCNBillboardConstraint</code> to ensure they are facing the right way. These videos are also partially transparent, using a custom shader on the <code>SCNMaterial</code> we apply (thus playing 2 videos at once).</p>
  
  <p>Now we have some issues where the people's occlusion is very iffy (see image). The video we are using to test is a woman with dark pants and a skirt (if you were wondering what the black is in the image).</p>
  
  <p>The issues we have are that the occlusion does not always line up with the person (as visible in the picture), and that someone's hair is not always correctly detected.</p>
  
  <p>Now our question is what causes these issues? And how can we improve the problems until they look like <a href="https://www.youtube.com/watch?v=vkS-VqAss4s" rel="nofollow noreferrer">this</a>? We are currently exploring if the issues are because we are using a plane, but simply using a <code>SCNBox</code> does not fix the problem.</p>
  
  <p><a href="https://i.stack.imgur.com/hmvY5.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/hmvY5.jpg" alt="enter image description here"></a></p>