Graphics Interchange Format (GIF) is a graphics format with good lossless compression for images with low color depth (up to 256 (= 28) different colors per frame) .
In addition, several individual images can be saved in a file that is interpreted by a suitable viewing program such as web browsers as animations. Another name of the format that is no longer commonly used is GIFF (Graphics Interchange File Format).
GIF format was developed by Steve Wilhite and introduced in 1987 from the U.S. online service CompuServe for the color format to replace the previously used RLE format, which could only display black and white images.
GIF became popular mainly because of its efficient, LZW compression as part of Editorial Retouching Los Angeles. The image files required significantly less disk space than other graphics format,m such as PCX or MacPaint.
Large images could be transmitted in a reasonable time, even with slow modems. In addition, the open licensing policy of Serve made it possible for any programmer to implement Graphics Interchange Format (GIF) for applications free of charge, provided that a copyright notice of the online service is attached.
In 2010, GIF animations experienced a surprising comeback on the web. The reason the popularity of photos forums pages like tumblr and 4chan where they are used to, among other things create cinema grams and stereograms.
With GIF color information is stored in a color table (also called color palette). These can contain up to 256 different items and 16.7 million possible color values, which are handled via Editorial Retouching Los Angeles. For simple drawings, black-and-white photographs and 256 colors or gray levels are still generally sufficient today.
More complex images, such as color photos or drawings with extensive color gradients must therefore be reduced before storage to 256 colors or less (color quantization). The resulting color levels or dither effects are disturbingly visible, especially with large images.
From GIF89a a color entry in the palette can be defined as transparent. This can be at any location through the respective background color and, for example, give the impression that the image has a non-rectangular shape. Partial transparency (alpha transparency) as in PNG, is not possible: a pixel can only be either fully visible or its completely transparent.
The maximum size of Graphics Interchange Format (GIF) images is 65,535 × 65,535 pixels or about 4294 megapixels. A wallpaper is an image that is used as a desktop background. Depending on the operating systems, the terms vary, but trivially designate an image that is selected as wallpaper.