In 2012, the American wing of the Oxford University Press recognized GIF as a verb as well, meaning "to create a GIF file", as in "GIFing was the perfect medium for sharing scenes from the Summer Olympics". Terminology Īs a noun, the word GIF is found in the newer editions of many dictionaries. In January 2018 Instagram also added GIF stickers to the story mode. In May 2015 Facebook added support for GIF. The optional interlacing feature, which stores image scan lines out of order in such a fashion that even a partially downloaded image was somewhat recognizable, also helped GIF's popularity, as a user could abort the download if it was not what was required. The feature of storing multiple images in one file, accompanied by control data, is used extensively on the Web to produce simple animations. In 2004, all patents relating to the proprietary compression used for GIF expired. Controversy over the licensing agreement between Unisys and CompuServe in 1994 spurred the development of the Portable Network Graphics (PNG) standard. While GIF was developed by CompuServe, it used the Lempel–Ziv–Welch (LZW) lossless data compression algorithm patented by Unisys in 1985. In September 1995 Netscape Navigator 2.0 added the ability for animated GIFs to loop. GIF was one of the first two image formats commonly used on Web sites, the other being the black-and-white XBM. By December 1987, for example, an Apple IIGS user could view pictures created on an Atari ST or Commodore 64. The two versions can be distinguished by looking at the first six bytes of the file (the " magic number" or signature), which, when interpreted as ASCII, read "GIF87a" or "GIF89a", respectively.ĬompuServe encouraged the adoption of GIF by providing downloadable conversion utilities for many computers. As there is little control over display fonts, however, this feature is rarely used. allowing text labels as text (not embedding them in the graphical data).storage of application-specific metadata.In 1989, CompuServe released an enhanced version, called 89a, This version added: This version already supported multiple images in a stream. The original version of GIF was called 87a. Since this was more efficient than the run-length encoding used by PCX and MacPaint, fairly large images could be downloaded reasonably quickly even with slow modems. GIF became popular because it used Lempel–Ziv–Welch data compression. This replaced their earlier run-length encoding format, which was black and white only. History įurther information: § Unisys and LZW patent enforcementĬompuServe introduced GIF on 15 June 1987 to provide a color image format for their file downloading areas. These replacements, in turn, are often termed "GIFs" despite having no relation to the original file format. While once in widespread usage on the World Wide Web because of its wide implementation and portability between applications and operating systems, usage of the format has declined for space and quality reasons, often being replaced with video formats such as the MP4 file format. GIF images are compressed using the Lempel–Ziv–Welch (LZW) lossless data compression technique to reduce the file size without degrading the visual quality. These palette limitations make GIF less suitable for reproducing color photographs and other images with color gradients but well-suited for simpler images such as graphics or logos with solid areas of color. It can also represent multiple images in a file, which can be used for animations, and allows a separate palette of up to 256 colors for each frame. The format can contain up to 8 bits per pixel, allowing a single image to reference its own palette of up to 256 different colors chosen from the 24-bit RGB color space. The Graphics Interchange Format ( GIF / ɡ ɪ f/ GHIF or / dʒ ɪ f/ JIF, see pronunciation) is a bitmap image format that was developed by a team at the online services provider CompuServe led by American computer scientist Steve Wilhite and released on June 15, 1987.
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