title: Using ImageMagick to repeat or "tile" an image
body: <p>How do I tile an image using ImageMagick?  I don't think I can use <code>montage</code> because I want the columns displaced by 50% of the original image height.</p>
  
  <p>It's probably easier to show an example of what I'm trying to do:</p>
  
  <p>Start with:</p>
  
  <p><img src="https://i.stack.imgur.com/o27AI.png" alt="enter image description here"></p>
  
  <p>End with:</p>
  
  <p><img src="https://i.stack.imgur.com/qOeBY.png" alt="enter image description here"></p>
  
  <p>Thanks!</p>