title: ImageMagick : improve text quality in scanned image
body: <p>i have been able to improve the text from a scan by adjusting the brightness and contrast with magick from ImageMagick. Also i reduced by ~10 times the file size by reducing the number of colors and depth. I'd like to know if some improvement can be suggested for making the text edges more sharp. below is my command, and the result.</p>
  <pre><code>magick myfile.png -brightness-contrast -20x40 -depth 4 -colors 4 myfile_2.png
  </code></pre>
  <p><a href="https://i.stack.imgur.com/bHFgr.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/bHFgr.png" alt="original scan" /></a></p>
  <p><a href="https://i.stack.imgur.com/yq8kW.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/yq8kW.png" alt="magick result" /></a></p>