Copyright © 2001 Hauke Hildebrandt
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License".
KView is an image viewing program. It is small and fast and has some simple image processing commands. You can work with many different graphic file formats and convert your images to them. KView is not a fully-fledged image processor but it is sufficient for many of your everyday tasks (like making a nice new desktop background...).
Table of Contents
Introduction
KView is an image viewer for the KDE desktop. You can view graphics of many different formats such as PostScript®, TIFF etc. By saving your files in a different format than the original you can easily convert images to other graphics formats. In addition, KView provides some nice little features for doing simple image processing, like stretching/shrinking, rotation and filtering. You can tile your images directly onto the desktop as a background picture, or arrange them in a little slideshow.
A sample KView session
This chapter is a quick tour through many of KView's functions to get you quickly going to work with this program. You will find a complete description of all available commands in later chapters.
The image in this tutorial comes from the kdeartwork package of KDE. The kdeartwork package is full of things to spice up your desktop, and well worth checking out, but if you haven't installed it, just choose another file to follow along with.
After you have started KView (using the panel menu, or typing kview at the command prompt) the KView main window shows up with an empty workspace:
A fresh new KView window
All those creative people like you and me are discouraged by an empty sheet, so let's quickly open a new image. However, first we change the way that KView resizes its main window and the image after loading a new one: Select Configure KView from the Settings menu. A dialog leaps up:
To resize or not to resize
Select “No Resize” from the “On Load” group box. This means that neither the KView main window nor the image will be resized after loading.
Now open Dasding.jpg which you find in the ./share/wallpapers subdirectory of your main KDE path (possibly /opt/kde or /opt/kde2). Ahh - that's looking better!
A beautiful image loaded...
The cutting edge
Let's make a new background wallpaper out of the loaded image. We only need the KDE logo (the gear-wheel on the right), not the whole picture, so select the logo by drawing a box around it. Press the left mouse button, hold it down and move the mouse. A dashed box appears, marking your selection. Repeat this until you are happy with your choice. Then go on and cut the selected region from the image by choosing Edit->Crop from the menu bar or it's equivalent shortcut, Ctrl+C. Your workspace should now look like this:
Reduced to the essentials
If you are not satisfied with the cutting you can always restore the image's original state with Edit->Reset, or the shortcut Ctrl+R.
Stirring the paste
We wanted to be creative, didn't we? KView provides some filter functions to manipulate images. They are (conveniently) placed in the Filter menu. Firstly, we will change the so-called “gamma factor”. This value affects mostly the mid-tones in the picture, leaving the brightest and darkest parts more or less untouched. Choose Filter->Intensity->Gamma correct from the menu bar. A dialog box appears. Change the value to 0.4 and hit the OK button. The picture is somehwat darker now:
After the gamma correction
For a little psychedelic touch we use the brightness function. Selecting Brightness again brings up a dialog. This time you can enter the new brightness expressed in percent relative to the original value (so 100 percent means “initial value”). Enter a value of 300.0300> and watch what happens:
KDE brighter than ever before
Finally, we blur the image a little with Filter->Smooth. Apply this filter two or three times (or more often if you can't stop!). The smoothing filter reduces the contrast between neighboring pixels:
KDE - smooth as silk
Cluttering up your desktop
Before we use our masterpiece as a desktop background we better save it. At the moment, our picture is a JPEG image, but for some reason we want to store it in the PNG format. Easy - just call File->Save As and enter a filename with the extension .png:
Saving and converting in one
The great moment has finally come: Choose Desktop->Desktop Tile and admire your incredibly artistic background:
KDE - wherever you look
Command Reference
When you start KView you see the typical application layout: a workspace containing your documents (images in this case), a menubar that provides access to the various commands, a toolbar with shortcut buttons for some of them and a status bar at the bottom to display status messages. When you have the loaded an image into KView, there is also an additional context menu available which is diplayed by clicking your right mouse button over the image (you knew that already, didn't you?). Below, all menu entries are explained in the order= that they appear in the menubar.
- File->Open (Ctrl+O)
Opens a new image in KView. The size of the KView main window and the image after loading are determined by your settings. If you open several images, only the last one is shown, but all of them can be accessed using the image list.
- File->Open Recent
Displays a list of recently opened images. Selecting one from this list reopens the image.
- File->Save (Ctrl+S)
Save the current image.
- File->Save As
Saves the image under a different name. By choosing a new file format you can convert the image to a different graphics type.
- File->Close (Ctrl-W)
Closes the currently displayed image.
- File->Print (Ctrl+P)
Prints the image.
- File->New Window (Ctrl+N)
Creates a new (empty) application window.
- File->Close Window (Ctrl+X)
Closes the currently active window. If you have only one window open this effectively finishes your KView session.
- File->Quit (Ctrl+Q)
Quits KView. If you have several KView windows open, all of them are closed.
The Edit Menu
- Edit->Fullscreen Mode (Ctrl+Shift+F)
This option maximizes the KView window and the currently shown image so you can have a closer look at it. Even the window decorations (titlebar etc) are temporarily removed. Selecting this option once again switches back to normal mode.
- Edit->Crop (C)
If you have selected any part of the image (by drawing a box around it using your mouse) you can cut off all the rest around it by using this option. Your image is effectively reduced to your selection.
- Edit->Reset (Ctrl+R)
Resets the image to its original state (right after opening it).
The View Menu
- View->Zoom...
Opens a dialog for editing the zoom factor. This value is given in percent and always refers to the initial size of the picture.
- View->Zoom In (Ctrl++)
Enlarges the image by ten percent. Notice that this refers to the current size of the picture.
- View->Zoom Out (Ctrl+-)
Reduces the image size by ten percent. Again this refers to the current size of the image.
- View->Double size (])
Doubles the current image size.
- View->Half size ([)
Cuts the image size by half. As above, this refers to the current image size.
- View->Max size (M)
Maximizes the image size. The image is scaled to the window size. This action does not preserve the aspect ratio.
- View->Max/aspect (A)
Maximizes the image size. Again, the image is size is maximized, but this time keeping the aspect ratio constant.
The Transform Menu
This menu offers commands for simple geometrical operations: rotation and reflection.
- Transform->Rotate clockwise (;)
Rotates the image by 90=B0 in the clockwise direction.
- Transform->Rotate anti-clockwise (,)
Rotates the image by 90=B0 in the counter-clockwise direction.
- Transform->Flip vertical (V)
Flips the image along the vertical. Mathematically, this does a reflection along the image's horizontal center line.
- Transform->Flip horizontal (H)
Flips the image along the horizontal. Mathematically, this does a reflection along the image's vertical center line.
The Desktop Menu
- Desktop->Desktop Tile
Tiles your image to the desktop background..
- Desktop->Desktop Max
Wallpapers your image to the desktop. This scales the image to the desktop size, possibly changing its aspect ratio.
- Desktop->Desktop Maxpect
Wallpapers your image to the desktop. This scales the image to the desktop size, but keeps its aspect ratio constant.
The Images Menu
KView provides some functions for simple image processing:
- Images->List...
Displays a list of the currently loaded images. You can flip through the images by either double-clicking on them or using the Previous and Next buttons. Shuffle rearranges the images in a random order, Sort arranges them alphabetically. Pressing Start Slideshow will start the slideshow with the current settings for interval and looping. In addition, you can save and load your image list using the corresponding buttons.
- Images->Back (Alt+Left Arrow)
Switches to the previous image in the list.
- Images->Forward (Alt+Right Arrow)
Switches to the next item in the list.
- Images->Slideshow On/Off (S)
Starts or stops the slideshow.
The Filter Menu
KView provides some functions for simple image processing:
- Filter->Intensity->Brightness
Changes the brightness of the image. Enter the new brightness in percent (with respect to the initial value).
- Filter->Intensity->Gamma Correct...
Adjusts the gamma factor.
- Filter->Greyscale
Converts a color image to a greyscale image.
- Filter->Smooth
Smoothes the image by reducing the contrast between neighboring pixels.
The Settings Menu
This menu provides options for configuring KView, changing its appearance, shortcuts and standard behavior.
- Settings->Show Menubar (Ctrl+M)
Toggles the menubar on/off.
- Settings->Show Toolbar
Toggles the toolbar on/off.
- Settings->Show Statusbar
Toggles the statusbar on/off.
- Settings->Save settings
Saves the current settings.
- Settings->Configure Key Bindings...
Opens a dialog for changing the key bindings. Using this option you can change the standard key shortcut for KView's commands or create new ones.
- Settings->Configure Toolbars...
Opens a dialog for configuring the toolbar. You can add and remove toolbuttons for KView's commands with this option.
- Settings->Configure KView...
Opens a dialog for changing some options and your keybindings:
- On Load
This option determines if the window and/or the image will be resized after loading a new picture into KView. With Resize Window enabled, the KView window will be resized so that it snuggly fits around the loaded image. Notice that this can reduce the main window almost to a vertical arrangement of menu entries if you load a small button pixmap (you can resize the window afterwards in the usual way, of course). If your image is pretty large (in terms of pixels), sometimes the KView window is resized in such a way that the caption bar completely moves off your screen. Similarly, Resize Image resizes the image to fit into the KView workspace (keeping its aspect ratio intact). And with No Resize as your choice, both KView and your image keep their size.
- Slideshow
Here you can change the parameters for the slideshow: the interval between the different slides, and if the show should continuously loop.
The Help Menu
- Help->Contents... (F1)
Invokes the KDE Help system starting at the KView help pages. (this document).
- Help->What's This? (Shift+F1)
Changes the mouse cursor to a combination arrow and question mark. Clicking on items within KView will open a help window (if one exists for the particular item) explaining the item's function.
- Help->Report Bug...
Opens the Bug report dialog where you can report a bug or request a ‘wishlist’ feature.
- Help->About KView
This will display version and author information.
- Help->About KDE
This displays the KDE version and other basic information.
Command Line Options
KView can be started directly from a terminal like Konsole or xterm. Several command line options are available.
- kview --help
Lists the command line options (see below).
- kview --help-qt
Shows the options specific to Qt™ (the GUI library that KDE is based on).
- kview --help-kde
Shows the KDE-specific options.
- kview --help-all
Displays all command line options.
- kview --author
You want to send your warm wishes and euphoric cheers to someone? Here they are!
- kview -v, --version
Displays the version number of KView (and that of Qt™/KDE).
- kview --license
Shows under which licenses KView is being published.
Credits and License
KView
Program copyright 1997-2001 Sirtaj S. Kang <taj@kde.org>
KParts integration by Simon Hausmann <shaus@neuro2.med.uni-magdeburg.de>
Maintainer: Matthias Kretz <kretz@kde.org>
Documentation copyright 2001 Hauke Hildebrandt <hauke.hildebrandt@iup.uni-heidelberg.de>
This documentation is licensed under the terms of the GNU Free Documentation License.
This program is licensed under the terms of the GNU General Public License.
Installation
KView is part of the KDE project http://www.kde.org/.
KView can be found in the kdegraphics package on ftp://ftp.kde.org/pub/kde/, the main FTP site of the KDE project.
In order to compile and install KView on your system, type the following in the base directory of the KView distribution:
% ./configure % make % make install
Since KView uses autoconf and automake you should have no trouble compiling it. Should you run into problems please report them to the KDE mailing lists.
Requirements
Since KView is part of the KDE desktop you need a working KDE installation to use it. However, some additional libraries are needed by KView to use the various graphics file formats. For example, to handle the PNG format KView needs the corresponding library libpng. KView uses the libraries that are registered by kdelibs/kimgio. Currently, libtiff, libpng and libjpeg are supported.