I need help integrating an RGB LED into my Wall Plotter.

I have committed to this school project and cannot turn back. We must create a wall plotter that will not only control the stepper motors (I have the basics for that) but also a common cathode RGB LED, changing color and intensity to create photographic art. The rig will operate in a dark room with a camera capturing HD open shutter exposures.

There is software available for DIY wall plotters that convert existing digital images to grey scale, then to monochrome black and white, then to plotter paths. I need a color component inserted into that process that will control provide the data I need to control the LED on the fly. I need a place to begin. Here are the questions I have. (Please don't laugh)

  1. Can a single Arduino UNO do the job? (control the steppers and the LED at the same time from the same file?)
  2. Is it possible there are programs available that will generate the color plotter files I need? Keep in mind that old school plotters changed pens, I won't need to do that. It is a continuous line that can change colors continually, like a single pixel that roams around. Am I making sense? It is intended to be a tool for digital art. The applications of it will be where the creativity comes in.
  3. Is there some kind soul out there who would like to hold our (My team's) hands through this?

Thank You!

Just to clarify, I fully intend to write the code for the Arduino and then post what I come up with for feedback, but without the image data format, I won't know where to begin. A nudge in the right direction will help.

One image format is g code. A wall plotter typically draws vector graphics. Inkscape is a free vector graphics editor, with which you do marvelous things. You can turn your images into g code, which your plotter will understand in terms of something like move-pen-ro-xy, pen-down, use-color#xxxxxx and so on.

That's all I know about g code. Do some googling on Inkscape, g code and CNC machines.