The GNU Image Manipulation Program

As mentioned earlier, the GIMP is the primary digital image manipulation package that is shipped with Ubuntu. It is designed to work very much like Adobe's popular Photoshop application, with a few exceptions (See the sidebar What Does Photoshop Have That Isn't in the GIMP?). However, it is free and has access to a range of plugins designed to enhance and extend the functionality of the GIMP.

The GIMP can be found under the Applications, Graphics menu or can be started by using the command line, like this:

$ gimp & 

You will see an installation dialog box when the GIMP is started for the first time, and then a series of dialog boxes that display information regarding the creation and contents of a local GIMP directory. This directory contains personal settings, preferences, external application resource files, temporary files, and symbolic links to external software tools used by the editor.

What Does Photoshop Have That Isn't in the GIMP?

Although the GIMP is powerful, it does lack two features Adobe Photoshop offers that are important to some graphics professionals.

The first of these is the capability to generate color separations for commercial press printers (CMYK for the colors cyan, magenta, yellow, and key [or black] ). The GIMP uses RGB (red, green, and blue), which is great for video display, but not so great for printing presses. The second feature the GIMP lacks is the use of Pantone colors (a patented color specification) to ensure accurate color matching.

If these features are unimportant to you, the GIMP is an excellent tool. If you must use Adobe Photoshop, the current version of CodeWeavers' CrossOver Office will run Photoshop in Linux.

Although longed after for quite some time, these features show no sign of making it into the GIMP in the very near future.

After the initial configuration has finished, the GIMP's main windows and toolboxes appear. The GIMP's main window contains tools used for selecting, drawing, moving, view enlarging or reducing, airbrushing, painting, smudging, copying, filling, and selecting color. Depending on the version installed on your system, the toolbox can host more than 25 different tools.

The toolbox's File, Xtns, and Help menus are used for file operations (including the capability to send the current image by electronic mail), image acquisition or manipulation, and documentation, respectively. If you right-click an open image window, you will see the wealth of the GIMP's menus, as shown in Figure 11.1.

Figure 11.1. Right-click on an image window to access the GIMP's cascading menus.