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GIF

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The Graphics Interchange Format, commonly known as GIF, is a bitmap image format that was introduced by CompuServe in 1987. It’s unique for its ability to support animations, which was enhanced in the 1989 version, known as 89a. This format can contain up to 256 colors per image, and each image or frame can have a separate palette of colors. GIFs are compressed using the Lempel-Ziv-Welch technique, which reduces file size without losing data. Despite its color palette limitations making it less suitable for color photographs, the GIF format has been widely used in various areas, including research and journalism. However, the usage has declined due to quality and space concerns, with formats like MP4 becoming more common. Despite this, GIF remains an important tool for sharing scenes and conveying messages on the web.

GIF (Wikipedia)

Les Graphics Interchange Format (GIF; /ɡɪf/ GHIF ou /ɪf/ JIF,) 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.

GIF
Filename extension
.gif
Internet media type
image/gif
Type codeGIFf
Uniform Type Identifier (UTI)com.compuserve.gif
Magic numberGIF87a/GIF89a
Developed byCompuServe
Initial release15 June 1987; 36 years ago (1987-06-15)
Latest release
89a
1989; 35 years ago (1989)
Type of formatlossless bitmap image format
Site webwww.w3.org/Graphics/GIF/spec-gif89a.txt

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. 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. 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.

GIF images are compressed using the Lempel–Ziv–Welch (LZW) lossless data compression technique to reduce the file size without degrading the visual quality.

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. These replacements, in turn, are often termed "GIFs" despite having no relation to the original file format.

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