Row Column Button description
1 1 Selects rectangular regions
2 Selects elliptical regions 3 Selects hand-drawn regions
2 1 Selects contiguous regions
2 Selects regions using Bezier curves 3 Selects shapes from images
3 1 Moves layers and sections
2 Zooms in and out
3 Crops the image
4 1 Transforms the layer or selected area 2 Flips the layer or selected area 3 Adds text to the image
5 1 Picks colors from the image
2 Fills area with a color or pattern 3 Fills area with a color gradient
6 1 Draws sharp pencil strokes
2 Paints fuzzy brush strokes
3 Erases to background or transparency
7 1 Airbrushes with variable pressure
2 Paints using patterns or image regions
3 Blurs or sharpens
8 Selects foreground/background colors
Because of the way Gimp was built, custom plug-ins allow graphics artists to create the effects they look for in the creations they make. The Gimp Web page
(www.gimp.org) references links to sample pages of plug-in effects. With a little
programming skill, you can write your own plug-in. This book covers more than one application, so I leave programming for Gimp to another time.
For a good introduction to programming plug-ins, look at www.oberlin.edu/
~kturner/gimp/doc/. This is a great site for beginning and advanced program-mers to learn to create plug-ins for Gimp.
Other features that you can add to this program include custom palettes, fonts, pat-terns, brushes, gradients, and scripts. You can find some of these available to download from the Gimp Web site under the resources section. Use them to create new, amazing computer graphics.
Gimp is very useful if you want to touch up a photo, change the contrast, rotate the image, or apply some special effect. Figure 7-5 shows a photo about to be rotated to the correct orientation for viewing onscreen. To rotate an image, right-click the image to view the menu. Move the mouse to Image where another menu appears.
Again, move the mouse to the Transforms menu item and then click Rotate from the third menu layer. A dialog box appears, and you can choose how many degrees to rotate. Once you select the rotation, click the OK button.
Figure 7-5: You can make changes to a photograph as simple as rotating an image or as complex as touching up image defects.
Tip
If you want to create graphics for Web pages, cover art, or just for personal enjoy-ment, then you can find everything you need in Gimp. Using special effects such as bevels, drop shadows, and chrome-it, you can create very unique art works. You can also take an existing photo of your family and turn it into an antique-looking photo. All these effects come as a result of the Script-Fu menu items, which come with the standard Debian install.
ImageMagick
Another powerful graphics manipulation program is ImageMagick. This program limits you to creating simple graphics as compared with Gimp. However,
ImageMagick does enable you to make changes to existing graphics, which is its real power. If all you ever need to do is manipulate images by cropping, resizing, rotating, or other such procedures, then look no further.
To install ImageMagick, use dselectto find and select the program named
imagemagickfor installation. The package installs the suite of programs that make up ImageMagick. Once the program is installed, you can launch it through the win-dow manager’s application menu by looking under Viewers. Officially, the Debian install of ImageMagick considers itself a viewer instead of belonging to the graphics category and is found in the Debian menu tree.
Navigating ImageMagick’s main menu is simple, as you can see from the left side of Figure 7-6. From this main menu, you can access all the different features this pro-gram has to offer. The main menu is broken down into functional groups. File, Edit, and View control the opening, saving, and viewing of the working image. Transform and Enhance control the overall changes to the image, while Effects and F/X apply special characteristics to the image. The following list details more explicitly what each of the main menu buttons enables you to do.
✦File— From the File menu, you can open an existing file or grab an image on the screen. This comes in handy when capturing pictures to put in a book, like those shown in this chapter. You also save changes to an image through this menu button.
✦Edit— You can undo the last change made to an image from here. You can also cut, copy, and paste images you want to manipulate.
✦View— If the image is too small or too large for the screen, you can adjust the viewing area. Consider this the zoom function. You can also resize the image to give it a particular dimension for a Web page.
✦Transform— When you want to crop, rotate, or flop (also known as mirror), here is where you do it. These features are easy to operate, and they control the orientation of the image.
✦Enhance— Occasionally, you may wish to enhance an image by adjusting its brightness, hue, or saturation. These features adjust the tone of a picture;
they can turn a dark image that is hard to make out into a clear photo.
✦Effects— Sometimes you may want to make a few buttons for a Web page or labels for a presentation. From here, you can take a 2-dimensional image and turn it into a work of art by using one of these features. You can emboss, sharpen, or raise the edges of an image.
✦F/X— You have five special effects available here. Each one is designed to take a normal photo and turn it into something unique. These five features are Solarize, Swirl, Implode, Wave, and Oil Painting. Give them a try to see how you like them.
✦Image Edit— There are limited basic tools available to create, customize, or add to an image. Here you can draw simple shapes, add borders and frames, or change colors.
✦Miscellany— Anything that doesn’t fit in one of the other categories finds its way here. Mostly you find preview features, but preferences show up here as well. The preference settings control eight settings, including how much mem-ory is used as cache.
✦Help— Help is just that — access to an overview and online documentation.
ImageMagick may not be the best tool for creating images from scratch, but it does make an excellent tool for manipulating photos and existing graphics for Web use.
Some applications produce PostScript output that printers interpret to produce the desired graphics. This output can get routed to a file that PostScript viewers can read. The program, ghostview, reads these PostScript files and displays the infor-mation in the same way a PostScript printer prints the inforinfor-mation.
Figure 7-6: ImageMagick showing a picture of a cute puppy.
Note
Browsers
For some time, the only browser available on the Linux system was Lynx — a non-graphical HTML browser. This worked fine when the sites were mostly textual.
However, with the advent of more sophisticated Web page designs, the need for a graphical based browser arose. Here entered Netscape, which joined in the Open Source community and offered a graphical browser to the graphical Linux desktop.
Outside of the text browser, Lynx, there are three main graphical browsers — but only one that isn’t included in any Debian release. Opera is the only browser not included in the Debian distributions because it is not free software. Netscape and Mozilla are free and are therefore included in the Debian release.
Lynx
With today’s Web pages becoming more graphical all the time, a text browser may not be very useful. So why bother mentioning it? I include it in this discussion for the simple reason that a graphical browser is useless when used through a terminal session. You’d be surprised the information you can glean from the text on a Web page. For instance, the Debian Web page contains numerous references, tidbits, and morsels buried in the page’s text.
Lynx is a full-fledged browser, so you can also use it for FTP sites or for transferring files like any other browser. Even though the FTP client is text-based and usable through a terminal, Lynx gives you alternatives.
You can use Lynx from any command line, even through a remote connection. Here is the syntax for using this browser:
lynx [options] [path or URL]
There are a number of options available for use with Lynx. Table 7-3 shows only a few of those options. You can find a full listing when you look through the documentation.
When you install Lynx, part of the configuration asks for the default path for the browser. If you launch Lynx without a path or Uniform Resource Locator (URL), then the default path is used. Otherwise, Lynx points to any file or URL path you enter.
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