Wallpaper (also desktop picture and desktop background ) is an image used as a background on a computer screen, usually for the desktop of a graphical user interface. "Wallpaper" is the term used in Microsoft Windows before Windows 7 (where it is called the Desktop "Background"), while Mac OS X calls it a "desktop picture" (previously, the term desktop pattern was used to refer to a small pattern that was repeated to fill the screen).
Formats
Images used as computer wallpaper are usually raster graphics with the same size as the display resolution (for example 1024×768 pixels, or 1280×1024 pixels) in order to fill the whole background.
Dimensions
Many screen resolutions are proportional in a 4:3 ratio, so an image scaled to fit in a different-sized screen will still be the correct shape, although that scaling may impact quality. Common wallpaper resolutions are connected to common desktop resolutions: 800x600, 1024x768, 1280x1024 and 1600x1200.
Users with widescreen (16:9 or 16:10) monitors have different aspect ratio requirements for wallpaper, although images designed for standard (4:3) monitors can often be scaled or cropped to the correct shape without undue loss of quality.
Wallpapers are sometimes available in double-width versions (e.g. 2560×1024) for displaying on multi-monitor computers, where the image appears to fill two monitors.
Some display systems allow unconventionally-proportioned images (1:1, 2:1, or even 1:3) to be scaled without change of proportion, to fit the screen, whether it be 16:9 or 4:3. The image would be sized just large enough that one pair of edges touch the edges of the screen, but not all four, as this would unduly distort the image. In these cases, the system's "default" background color is visible around the other two sides of the image.
Technical aspects
The main problem when enlarging an image to match the desktop resolution is the quality loss that appears during the resize process and the distorted image that appear when aspect ratio of the wallpaper is different than the aspect ratio of the desktop. However, there are applications that can automatically decide if an image is better to be displayed using its original resolution, resized (enlarge or shrink) or tiled. For example, BioniX Wallpaper Changer can automatically detect when the wallpaper image is smaller than the desktop or it has a different aspect ratio and apply special image processing to make the discrepancy less visible. The process is backed up by a high-resolution resampling (using special resampling algorithms like B-Spline) in order to decrease the quality loss during image resizing. Even if the resulted wallpaper may not always match the desktop resolution and aspect ratio perfectly, the uncovered areas are generally reduced.
These problems can be eliminated by using vector images. However, these images are not very popular and are hard to find.
Image types
PNG and JPEG format are common. Some desktop systems, such as Mac OS (version 8.6 or later), KDE (version 3.4 or later), and GNOME, support vector wallpapers (PICT in Mac and SVG in KDE and GNOME). This has the advantage that a single file may be used for screens of any size, or stretched across several screens, without loss of quality.
Most display systems are capable of specifying a single colour to use as the background in place of a wallpaper, and some (such as KDE or GNOME) allow colour-gradients to be specified. Early versions of Mac OS and Microsoft Windows allowed for small repeating patterns to tile the desktop.
History
The first use of a distinguishable background in conjunction with overlapping windows was in an experimental office system, Officetalk, developed in 1975 at Xerox PARC on the Alto. Prior to that, the white backgrounds to overlapping windows (for example, in Smalltalk) could be difficult to distinguish from window interiors. The pattern used in Officetalk produced a 25% gray, using dots two pixels high to avoid flicker on the Alto's interlaced screen. The same pattern was adopted for the Xerox Star.
Apple used a similar gray background for their Lisa and Macintosh. However, since these machines had non-interlaced screens it was possible to use a less noticeable background pattern, formed from a simple 2x2 repeating pattern that gave a 50 percent gray. The introduction of color monitors for personal computers led to non-patterned, single-color backgrounds and then to arbitrary 'wallpapers'. There was a way to get a desktop picture on versions of the Mac OS before Mac OS 7.
Styles
In Personal Use
Wallpapers used usually fall into one of the following categories: automobiles, models and celebrities, scenery, abstract art, movies, pets, family, symmetry, and personal photos.
In environments such as GNOME and Windows, wallpapers may be packaged along with desktop themes.
In Business Use
It is common to use corporate logos or plain backgrounds on business computers, as such guidelines are often specified by the company.
It is common to create wallpaper that displays a computer's name when using rack mounted computers through a KVM switch in order to easily identify to which computer the user is connected. Many companies will disable the display settings so the staff can't change the background, however this is often easy to get around for example: using the "set image as background" button in many web browsers.
Dynamic backgrounds
Some operating environments (e.g. KDE, Mac OS X, and Windows 7) allow a number of different wallpapers to be used, and changed from a set of selected images (either in order or shuffled) to display a different wallpaper at different times. In environments where this is not possible off-hand, third-party tools may be able to have this be done.
In Microsoft Windows
Windows 98, Windows 2000, Windows Me and Windows XP supported Active Desktop, a component that allowed dynamic web pages and Adobe Flash to be used as desktop wallpapers. Active Desktop was discontinued on Windows Vista.
On Windows Vista Ultimate, Windows DreamScene had the ability to use a video clip or animation as a wallpaper. The animation looped continuously. Windows DreamScene was discontinued on Windows 7.
On Windows 7, Desktop Slideshow allows users to specify a group of image which Windows 7 displays on desktop one at a time for a specified period of time.
With Video Media
Some media players, like VLC, can redirect video playback to the desktop, allowing any video to be used as a wallpaper. Other such media players on Unix derivatives provide a similar option to output video to the background of X11.
Real-Time
Programs such as Xplanet and EarthDesk use Internet connections and graphics calculations to change the wallpaper with real data, such as a shadowed view of the earth, the latest cloud or weather map, or various events.
See also
- Category:Wikipedia featured desktop backgrounds
- Bliss
- Digital Blasphemy
- Caedes
- VRML wallpaper
- Wallpaper group
References
Desk Picture - Free Wallpaper and Backgrounds
Welcome to DeskPicture.com Free Wallpaper and Backgrounds A growing collection of free desktop wallpaper and backgrounds for your use and enjoyment
Free Religious Desktop Wallpaper Backgrounds
Over 1000 free religious desktop wallpaper backgrounds that you can use for your desktop wallpapers.
Free Wallpapers for your Desktop - iPhone wallpapers
Free Wallpapers - Desktop Ones from WallpaperFree.co.uk Desktop Wallpapers ... Cool Desktop Backgrounds Free Nature Wallpaper
Free desktop wallpaper, free backgrounds - Icehouse Designs
Free 3D wallpaper, free backgrounds ... Free Wallpaper ( Click here to add your wallpaper to this directory!
Cognitive Distortion - Desktop wallpaper free 3d computer backgrounds.
Cognitive Distortion - Desktop wallpaper free 3d computer backgrounds.Free 3D desktop wallpaper, wallpaper borders, myspace background, quotes and art for you computer.
Free Wallpapers, Desktop Wallpaper, Backgrounds and Desktop Themes ...
Free wallpapers, desktop themes, and interactive backgrounds for your computer. Find free desktop wallpaper and pictures in many styles for Windows and Mac platforms.
Desktop Wallpapers · Free Wallpapers | 1024x768
Wallpaper Free 1024 x 768 ... Desktop Wallpapers · Free Wallpapers · Desktop Backgrounds
Free Wallpapers | Wallpaper | MySpace Backgrounds | Free Wallpapers ...
Your source for free desktop wallpaper, stock photos and backgrounds. Updated daily.
Desktop Wallpaper · Top Wallpapers | Desktop Backgrounds
Top20 Free Wallpapers: iPhone Wallpapers: Desktop-3D ... Desktop Backgrounds All popular resolution: Standart Resolutions: ... Copyright © 2002 - 2009 Desktop wallpaper Fantom-XP Inc.
Free wallpaper - High Resolution Desktop Wallpapers
Free wallpaper from great photos categories of 3D, Animals, Christmas, Celebrity sexy girls, Widescreen, PSP background and screensaver for download, free wallpaper, desktop ...