title: Generating QR codes
body: <p>I am writing an application which is going to generate qr codes.</p>
  
  <p>Most of the programming logic is implemented.</p>
  
  <p>The next step in the process would be to generate the qr code image.</p>
  
  <p>The most simple qr code is based on a 21x21 grid in which I have to make a tile (1x1) either black / white.</p>
  
  <p>For more info: <a href="http://www.thonky.com/qr-code-tutorial/part-3-mask-pattern/" rel="nofollow noreferrer">http://www.thonky.com/qr-code-tutorial/part-3-mask-pattern/</a></p>
  
  <p>What would be the best approach for this.</p>
  
  <p>I need to:</p>
  
  <ol>
  <li><p>Show a preview of the code in the application</p></li>
  <li><p>Give the user the option to save the qr code as an image (.jpg I think).</p></li>
  </ol>
  
  <p>I.e. how to make an image which can be build like above and how to save it?</p>