IDEA No 18
GRAPHICS INTERCHANGE FORMAT
Webpages, social networks, blogs, email, message boards, banner ads. Other than HTML, one thing is consistent across them all – the graphics interchange format (GIF).
Dancing Girl by legendary GIF artist Chuck Poynter.
It’s 20 years old. It supports only 256 colours. It’s unsuitable for photographs. It has no sound capability. It’s inferior to the PNG (see below). Yet the GIF is still hanging in there. Why has it proved so tenacious? Because it can move.
CompuServe introduced the GIF format in the pre-Web days of 1987. It was released as a free and open specification for sharing colour images across their network.
A GIF supports 8 bits per pixel. This allows it to reference 256 distinct colours (28), chosen from a palette of millions. Each of these colours is stored in a table and given a value. When neighbouring pixels are the same colour, the run-length is specified followed by the colour value. This is called LZW data compression, after its creators Abraham Lempel, Jacob Ziv and Terry Welch. It means images can be downloaded reasonably quickly, even with slow modems.
LZW compression was described by Welch in the June 1984 issue of the Institute of Electrical and Electronics Engineers (IEEE) magazine. It soon became the most popular form of data compression. What the article did not mention was that Unisys held a patent on the algorithm.
GIFs really took off in 1993 with the release of Mosaic, the first graphical browser. Mosaic introduced the <img> tag, which supported two formats – GIF and a black-and-white format called XBM. Mosaic became Netscape and, as it grew, the GIF grew with it.
In 1994, Unisys decided to enforce its patent, announcing that developers would have to pay a licence fee to use their algorithm. This caused outrage. It turned out that the patent covered the software that made GIFs, not the files themselves, but it was enough for a working group to come up with a new format, portable network graphics (PNG). The PNG was adopted by the World Wide Web Consortium (W3C) as a standard. The GIF looked doomed.
In 1996, Netscape 2.0 was released. It supported GIF animations – multiple frames shown in succession. The Web went crazy. Suddenly there were spinning logos, animated underconstruction signs and dancing babies (see Viral Content) everywhere you looked. The PNG does not support animation.
The LZW patents expired in 2004. Since then, Myspace and Tumblr have attracted a new generation of GIF artists. Called ‘the spirit of the Web’ by artist and GIF model Olia Lialina (see Net Art), it is the limitations of the GIF that have made it so attractive. Within minutes, a GIF animation can be made and viewed, often without the need to click on a link. Sometimes the old ways are the best ways.■
‘It’s 20 years old. It supports only 256 colours. It’s unsuitable for photographs. It has no sound capability. … Yet the GIF is still hanging in there. ’
GIF artwork created for German magazine Der Spiegel by eBoy.