For those who do a lot of graphic work, you might know about the limitations of bicubic scaling. It works great if you are resizing an image and maintaining the aspect ratio, but if you want to change the aspect ratio, you get distortion. A little demonstration here. Note that in order to fit these images in the journal, I'm displaying them at 1/4 size, which isn't adequate to show the differences. You can click on any image to bring up the full size version in a separate window.



So what to do? The answer is liquid rescaling. Liquid rescaling is an algorithm for scaling images along one dimension (like width) without distortion. It allows you to change the aspect ratio of a photo. The GIMP has a liquid rescaling plug-in, which allows you to do this. I basically had to create a separate layer as a mask for the dog and the man, and a few of the background trees. Then I applied the plug-in, and voila, you have a new image aspect ratio without distorting the salient details of the picture.

And to demonstrate, here's the same picture, same aspect ratio change as the previous one, but using liquid rescaling.



Of course you need the GIMP for this. There is no Photoshop equivalent as of yet. You can get the GIMP at http://www.gimp.org. You might have to follow links out to get it for windows or mac.

Then you need the plug-in, which you can get here: Liquid Rescale GIMP plugin.