GIMP Bible

Chapter 15. Using Compositing Filters

IN THIS CHAPTER

• Using edge detection for advanced compositing

• Taking advantage of GIMP's sadly misnamed "Generic" filters

• Using one image to create another

Because it is an image editor with an advanced layers system, one of GIMP's primary uses is that of a compositing tool. In computer graphics, compositing is the art of mixing multiple graphic elements together to attain a specific visual look. A simple example of compositing would be if you take a picture of your friend and overlay text that says "Friend for Sale." You might not be friends for long after doing such a stunt, but you'd have a good example of compositing in your hands. In advanced compositing examples, you can mix an image with itself to give it an ethereal glow or you can change a daytime scene to look like it was taken at night.

Compositing consists of using a series of small steps and processes to influence the final look of your image. The filters described in this chapter play into that process because they're small, generally simple tools that can be used at each step to achieve the final composited result. Being as simple as they are, these tools are also often used for tasks that aren't directly related to compositing. I'll try to point out where a filter can be used as more than just a tool to help mix graphical elements together.

That said, the filters in this chapter offer some of GIMP's greatest abilities to dramatically influence the look of your final image, often completely ...