title: How to generate a Trimap image
body: <p>I found this dog and cat image dataset:</p>
  
  <p>The Oxford-IIIT Pet Dataset.</p>
  
  <p>Any idea how the pixel level foreground-background segmentation (trimap) image was generated?</p>
  
  <p>I want to use it for my own dataset.</p>
  
  <p>Pixel-level foreground-background segmentation</p>
  
  <p>an image with three colors (one for the background, one for the foreground and one for the not-classified region)</p>
  
  <p><a href="https://i.stack.imgur.com/FR5Ev.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/FR5Ev.png" alt="enter image description here"></a></p>