title: Golang convert raw image []byte to image.Image
body: <p>Suppose I have an 8-bit grayscale image like this:</p>
  
  <pre><code>var pixels []byte = ...
  width := 100
  height := 100
  </code></pre>
  
  <p>How do I convert that into something that implements <a href="https://golang.org/pkg/image/#Image" rel="noreferrer"><code>image.Image</code></a>?</p>