Red Hat Linux 7 Unleashed

By William Ball

• Table of Contents
  • Copyright
  • About the Lead Authors
  • About the Contributing Authors
  • Acknowledgments
  • Tell Us What You Think!
  • Introduction
  • I. Red Hat Linux Installation and User Services
  • Chapter 1. Introduction to Red Hat Linux
  • Chapter 2. Installation of Your Red Hat System
  • Chapter 3. LILO and Other Boot Managers
  • Chapter 4. Configuring the X Window System, Version 11
  • Chapter 5. Window Managers
  • Chapter 6. Connecting to the Internet
  • Chapter 7. IRC, ICQ, and Chat Clients
  • Chapter 8. Using Multimedia and Graphics Clients
    • Linux Graphic Utilities
    • Common Graphics Formats
    • Basic Graphic Editing Clients
    • Using the GIMP
    • Displaying and Printing Graphics
    • Configuring Sound
    • Playing Audio CDs
    • Playing .mp3s
    • Playing Video
    • Using a Web Cam
    • Summary
  • II. Configuring Services
  • Chapter 9. System Startup and Shutdown
  • Chapter 10. SMTP and Protocols
  • Chapter 11. FTP
  • Chapter 12. Apache Server
  • Chapter 13. Internet News
  • Chapter 14. Domain Name Service and Dynamic Host Configuration Protocol
  • Chapter 15. NIS: Network Information Service
  • Chapter 16. NFS: Network Filesystem
  • Chapter 17. Samba
  • III. System Administration and Management
  • Chapter 18. Linux Filesystems, Disks, and Other Devices
  • Chapter 19. Printing with Linux
  • Chapter 20. TCP/IP Network Management
  • Chapter 21. Linux System Administration
  • Chapter 22. Backup and Restore
  • Chapter 23. System Security
  • IV. Red Hat Development and Productivity
  • Chapter 24. Linux C/C++ Programming Tools
  • Chapter 25. Shell Scripting
  • Chapter 26. Automating Tasks
  • Chapter 27. Configuring and Building Kernels
  • Chapter 28. Emulators, Tools, and Window Clients
  • V. Appendixes
  • A. The Linux Documentation Project
  • B. Top Linux Commands and Utilities
  • C. The GNU General Public License
  • D. Red Hat Linux RPM Package Listings

Basic Graphic Editing Clients

This section introduces and lists some of the common graphics clients included with X11, GNOME, and the K Desktop Environment (KDE). You'll find a wealth of clients to use for simple graphics functions and editing. Although none of the these clients are as capable or comprehensive as the GNU Image Manipulation Program (GIMP; see Using the GIMP later in this chapter), you may discover practical uses in specific situations that will save time and effort when working with graphics.

X11 Graphics Clients

The X Window System has always included a number of graphics programs. Although most were developed to do one thing and to do that one thing well (like all good UNIX commands), some of the larger applications may seem a bit primitive to most Linux X11 desktop users today. Many provide just a bare minimum of functionality to get the job done, without all the frills of window decorations, buttons, or an overabundance of features.

Table 8.3 lists some common X11 graphics applications you'll find available for X and Red Hat Linux. One of the advantages of using these clients is that you'll rarely need to have specific, additional software libraries installed in order to make the client work—all the functionality is built into the client, and the client depends solely on the X11 software libraries.

Table 8.3. X11 Graphics Clients

Half of the clients listed in Table 8.3 may be used from the command line of an X11 terminal window, or in the case of the xwd client, from the text-only console command line. The xwd client is used to take a snapshot of a running client or the root display of an X11 session. The output of the xwd command is sent directly to the standard output, so you'll need to use file redirection or the -out command-line option, along with a filename to save your graphic.

For example, if you're running X, you can press Ctrl+Alt+F2 to jump to the second virtual console, then use the xwd client to take a snapshot of your current X session like this:

   # xwd -out shot1.xwd -root -display :0

You can also use xwd from the command line of an X11 terminal window like this:

   # xwd >out.xwd

After you press Enter, your cursor will turn into a cross-hair, and you can then click on another window or the root desktop to take a picture. To display your screenshot, you can use the xwud client like this:

   # xwud <out.xwd

After you press Enter, the image will be displayed in a window. Click on the window to end the program.

Taking Screenshots with the import Command

Another capable client you can use to take pictures of the root display or selected windows is the import command, part of John Cristy's ImageMagick software package. This command, like xwd, is used from the command line, but features on-the-fly sizing, cropping, and rotation operations, along with graphics conversion. You can also use this command to take screenshots of other computers on your network (as long as you're properly authorized, perhaps with the xhost command). And, like xwd, you can use the import command from the text-only console while an X11 session is running to take pictures of a root display.

For example, to take a picture of the desktop from the command line of an X11 terminal window, use the import command, along with its -window option and the root keyword, like this:

   # import -window root test.gif

This example will take a snapshot of the entire display and save it in GIF format in the file named test.gif. If you want to take a rotated snapshot of an X11 session on another computer in your LAN, you can use the import command's -display option with the hostname and display number and the -rotate option, like this:

   # import -window root -display vaio.home.org:0.0 -rotate -90 display.pcx

This example will take a portrait-oriented (90-degree) snapshot of the computer vaio.home.org's X11 session and save it in a PCX graphics file named display.pcx. The import command has more than 30 different command-line options you can use for varied effects!

GNOME-Enabled Graphics Clients

The advent of The Gnu Image Manipulation Program (GIMP) with its GTK+ Toolkit and GDK Drawing Kit libraries ushered in the growing popularity of the GNOME software libraries and GNOME-aware window managers for X11. This interest on the part of software developers and users has spurred further development of GNOME clients, including various graphic software utilities for the GNOME distribution. You'll find a number of graphics utilities included with GNOME on your Red Hat Linux system.

Some of the graphics utilities (listed in Table 8.4) are aimed at a specific purpose, such as viewing a particular graphics document (such as a fax), creating and editing icons, viewing various images (such as PostScript), converting graphics, or perhaps taking pictures of the desktop or windows during an X11 session.

Table 8.4. GNOME Graphics Clients

For example, the gphoto client will handily download images from a variety of digital cameras, then offer them for display in thumbnail views for editing. Connect your camera to your computer's serial port, then start the gphoto client from your GNOME desktop panel or the command line of a terminal window like this:

   # gphoto &

After you press Enter, you'll see the main gphoto dialog, as shown in Figure 8.1.

Figure 8.1 The gphoto client works with many different types of digital cameras.

Click the Configure menu, then click the Select Port-Camera Model menu item. You'll see a dialog, as shown in Figure 8.2.

Figure 8.2 The gphoto client must be configured for your camera before getting to work.

Click the drop-down menu to select your camera model, then click to select the proper serial port. When finished, click the Save button. To begin, click the thumbnail index icon on the toolbar, and gphoto will issue the proper instructions via the serial port to download images. You can also press Ctrl+I, or use the Camera menu to accomplish the same thing. When finished, you should see something like Figure 8.3.

Figure 8.3 To pick an image to edit with gphoto, first select a thumbnail image.

Using thumbnails is a faster way to view the contents of your camera's memory and to pick and choose an image. To download one or more images, click to select the desired thumbnails, then click the Download Selected Images button. When finished, gphoto will display the images in tabbed windows behind its main window, as shown in Figure 8.4. You can then use the various toolbar buttons to rotate, flip, resize, and adjust color balance, brightness, and contrast.

Figure 8.4 The gphoto client is a mini-photo editor, and can be used to organize, edit, and color-balance digital images!

K Desktop Environment Graphics Clients

Like GNOME, KDE depends on special software libraries for its special features, such as drag-and-drop and inter-client communication. Also like GNOME, KDE developers have created and fine-tuned numerous graphics applications for use with KDE.

Red Hat Linux includes the latest stable version of KDE, along with its host of clients; however, newer (but unstable) versions of KDE include many new graphics productivity clients. You'll find a number of these included on your Red Hat CD-ROM's /preview directory. Again, many of the graphics utilities (listed in Table 8.5) have a specific purpose, such as viewing graphics files or creating and editing icons.

Table 8.5. KDE Graphics Clients

Each KDE client listed in Table 8.5 features similar menus, toolbars, buttons, and dialogs. This is also the case for each of the GNOME clients listed in Table 8.4—the use of supporting software libraries provides a consistent interface across each environment's suite of tools.

As an example, the kchart client may be used to quickly plot numerical data and create 3D line, bar, or pie charts. Start the client by clicking its name from the desktop's panel, or by typing the command on the command line of a terminal window like this:

   # kchart &

After you press Enter, you'll see the initial window. Note that like other clients, kchart features a menu bar and a toolbar of graphic icons, along with a default chart graphic. (See Figure 8.5.)

Figure 8.5 The kchart client draws and saves graphs of data.

If you click on the graphic, a toolbar will appear. You can then change the default numerical data (using a mini-spreadsheet) and chart type.

Share This