title: How to add transparency to a PNG image with ImageMagick
body: <p><strong>How to add transparency to a PNG image using ImageMagick?</strong><br>
  <strong>How to reduce PNG file opacity using ImageMagick?</strong><br>
  <strong>How to modify a PNG's alpha channel using ImageMagick?</strong></p>
  
  <p>Use case:<br>
  You have several PNG images like this (Source opacity: 100%)<br>
  <a href="https://i.stack.imgur.com/2v4ma.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/2v4ma.png" alt="Source image"></a></p>
  
  <p>And what to increase their transparency like this (Target opacity: 70%)<br>
  <a href="https://i.stack.imgur.com/qUHre.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/qUHre.png" alt="Wished result"></a></p>
  
  <p>Using ImageMagick's <code>convert</code> command, allowing to script and process hundreds of icons at a time. </p>
  
  <p>(Note: Background pattern is only used to highlight transparency)</p>