title: How do I rotate an image in the frequency domain?
body: <p>I've heard that it should be possible to do a lossless rotation on a jpeg image. That means you do the rotation in the frequency domain without an IDCT. I've tried to google it but haven't found anything. Could someone bring some light to this?</p>
  
  <p>What I mean by lossless is that I don't lose any additional information in the rotation. And of course that's probably only possible when rotating multiples of 90 degrees. </p>