Create images w/ GD

I need a small script that generates every image (not at once) with adjustable size within the RGB space. The script needs to be able to store where it is in this gigantic onetime loop e.g. if the server goes down. It also must have the ability to save the created image with the click of a (html) button. So, make a script that loops though all images with a with of XxY, one button that saves the image on the server and one button to generate the next image in line. Image construction: Example 1: A one pixel image. Generate all those 16.581.375 images starting from black (#000000) to white (#FFFFFF). Example 2: A larger image (e.g. 2x2 pixels) where every pixel is black, start with the first pixel (1,1) and loop though all the 16.581.375 colors. When that is done, set the first pixel to black and change the second pixel (2,1) to #000001 and start looping the first pixel again and so on, and so on. Front end usage: A user loads the front end page (e.g. [login to view URL]) and the scrip looks up what was the last image it created and creates the next in line and displays it. The user then have the options to save the created image on the server or click next to show the next image in line. Is anything unclear? Tell me and I will try to explain better.