title: Combine (merge) images with drag & drop
body: <p>Image this scenario:
  There is a picture locally in my server, where a sketch is displayed, and there is a "blank hole" area on it.<br>
  Then, a user can upload another picture to my server.  </p>
  
  <p>What i'm trying to achieve is this:
  After image upload is finished, the first image (the one with the "hole") is displayed, and behind it is displayed the user's photo, so that you can see it through the "blank hole" area of the first photo.  </p>
  
  <p>Then the user can move his picture (drag &amp; drop style) so he can choose which area of it is visible through the "blank hole".
  Then i would like to save the result - by merging the 2 photos or keeping the position of the user's picture in a db so i can display it again later.<br>
  (Something like <a href="http://www.loonapix.com/framer/703-happy_xmas/" rel="nofollow">this</a> more or less)  </p>
  
  <p>What kind of technollogy should i look for? I'd guess javascript(for the drag &amp; drop) or html5 or php(for merging the photo)?<br>
  Are there any libraries that i can use?  </p>
  
  <p>I hope my explanation isn't too messy, i didn't even know how to google for it.</p>