Running Linux, Fourth Edition

Graphics

Many people are fascinated by computer graphics. Computers are being used to create photorealistic images of surreal scenes or fractally generated images of mountain ridges with lakes and valleys; to change images by bending, polishing, and aging them; or to make any other manipulations.

Linux does not need to step shyly aside when it comes to graphics. It can do just about anything that other computing environments can do, and in some areas, such as dealing with many graphics files at the same time, it even excels. The X Window System, described in the next chapter, forms a very good base for bitmapped graphics. There is now also hardware support for 3D graphics conforming to the OpenGL standard.

However, working with graphics on Linux is sometimes different from what you might be used to on other operating systems; the Unix model of small, interoperating tools is still alive and well here, too. This philosophy is illustrated most clearly with the ImageMagick suite of graphics manipulation programs, which we will describe here. ImageMagick is a collection of tools that operate on graphics files and are started from the command line or from shell scripts. Imagine that you have 2,000 files of one file format that you want to reduce to 256 colors, slant, and convert to another file format. On Linux, this requires only a few lines in a shell script. Now imagine doing this on Windows: click the File menu, click the Open menu entry, select a file, select an operation, specify ...