Morphing a Fisheye to Panorama

Question

Hello :)

Currently I want to code a program that morphs a fisheye image to a panorama image.

I found this really great page about transforming those images with some functions.

http://www.fisheyelens.de/html/pano-def.html (site is in German language)

Has someone of you worked with images and did works beyond resizing, coloring, stretching etc. ?

I'm totally new to work with images and also it's a difficult task. 

Because it seems that I have to re arrange every pixel with one of these functions and not 

only call one method for the complete picture.

So could you give me a hint on how to use these functions?

I hope it was understandable.