Format Born
CompuServe ships GIF87a in 1987. The Netscape loop extension, the JPEG and PNG rivals, and the early format wars that shape what the GIF actually is.
Part of GIfs
10 moments in this segment.
- — CompuServe Ships GIF87a. An interlaced GIF loading frame by frame over a simulated 28.8k modem, the exact viewing experience GIF87a was engineered to deliver to CompuServe subscribers. Place: CompuServe, Columbus, Ohio Figures: Steve Wilhite, lead developer · the CompuServe graphics team CompuServe needs an image format its subscribers can actually download. The competitors of 1987: JPEG was approved as ITU-T T.81 in September 1992 (five years after GIF87a), not two years. If 'standardization' is being measured against JPEG's earliest draft work, the working group was already organized in 1986; in either reading, 'two years from standardization' in 1987 is inaccurate., various platform-specific bitmaps (PCX, BMP) that don't compress well over a 1200-baud line. Steve Wilhite's team picks LZW (see [[lzw-patent-1985]]) for the compression and designs a container around it. The spec is small: a header, a logical-screen descriptor, optional global color table, a series of image blocks with local color tables, and a trailer. 256 colors maximum. Lossless. Cross-platform. Released to subscribers on 15 June 1987 as a free standard, with the famous note: GIF is intended as a free and open standard. The patent footnote will come later. Video: A short walk through the LZW dictionary scheme that Wilhite's team wrapped a header and color table around in 1987.
- — XAnim and Cross-Platform Playback. Newton's cradle as an animated GIF, the kind of small looping demo Unix users opened in XAnim through the early 1990s. Place: University of New Hampshire FTP site; later widely mirrored Figures: Mark Podlipec, author and sole maintainer Mark Podlipec releases XAnim in 1990 from his FTP site at the University of New Hampshire. It is a Unix command-line viewer that plays animated formats on the X Window System: GIF, FLI, FLC, IFF/ANIM, AVI, QuickTime MOV, MPEG, plus dozens of obscurer formats added over the years. The codebase is a single sprawling C project that compiles on any Unix with a frame buffer and Xlib. Through the early-to-mid 1990s, XAnim is the reference implementation for animated-GIF playback outside CompuServe's own Windows decoder. If a Unix workstation can display animation at all, it is because XAnim is installed. Sun, SGI, NeXT, HP-UX, AIX, every academic Unix box of the era. Podlipec maintains the codebase alone, releasing updates roughly monthly through 1996.
- — GIF89a and the Frame Loop. The canonical rotating Earth, the looping behavior that GIF89a's frame delay and graphic control blocks made possible. Place: CompuServe, Columbus, Ohio Figures: Steve Wilhite · CompuServe graphics team The 1989 revision adds application extension blocks: arbitrary metadata containers inside the file. One of them, the Netscape Navigator 2.0 application extension (added to common implementations in 1996), specifies a loop count. Combined with the format's existing ability to store multiple image frames and a per-frame delay, this turns the GIF from a still-image format into an animation container that any modern browser will autoplay. It is, in retrospect, a quiet revolution. The Web of 1996 has video as a download-and-launch-a-player affair. The GIF gives the page itself the ability to move. Video: Tumblr's David Karp hands Wilhite the lifetime achievement Webby. Wilhite's five-word speech is itself a GIF.
- — JPEG Standardized. JPEG quality sweep from Q90 to Q100 looped as a GIF, demonstrating the lossy tradeoff JPEG made standard in 1992. Place: ISO/IEC, Geneva (JTC 1/SC 29/WG 1) Figures: Joint Photographic Experts Group, chaired by Gregory K. Wallace · the ISO/IEC working group on still-image compression JPEG is approved as ITU-T Recommendation T.81 in September 1992 (published as ISO/IEC 10918-1 in 1994), five years after the GIF (see [[compuserve-ships-gif87a-1987]]) and four years before PNG (see [[png-released-1996]]). The technical premise is the opposite of GIF's: lossy compression optimized for photographs, using the discrete cosine transform to discard frequency information the human eye cannot easily perceive. Compression ratios of 10:1 to 50:1 are achievable with minimal perceptible loss on photographic content. On 256-color iconographic images, JPEG performs worse than GIF and introduces visible artifacts. On 16-million-color photographs, JPEG performs better than any lossless format by an order of magnitude. The two formats are designed for different content. The web of 1995 onward will use both, side by side, on the same pages. Video: Mike Pound opens Computerphile's JPEG series by explaining what the 1992 ISO standard actually specifies.
- — Mosaic Renders the GIF Inline. The NCSA Mosaic logo, itself a GIF, from the browser that put inline images into the document and built the visual grammar of the early web. Place: NCSA, University of Illinois at Urbana-Champaign Figures: Marc Andreessen, 21, lead developer · Eric Bina, principal engineer · the NCSA software development group Tim Berners-Lee's original WorldWideWeb browser at CERN displays images in separate windows. Marc Andreessen and Eric Bina, working on Mosaic at NCSA, decide images should appear inside the document, alongside the text, autoplaying their animations the moment the page renders. They implement the IMG tag with this behavior in Mosaic 1.0, shipped April 1993, free for Unix, Mac, and Windows. The format of choice is the GIF (see [[compuserve-ships-gif87a-1987]]). JPEG is too new and photographic; XBM is monochrome and ugly; PCX and BMP do not compress for the modem-speed web. The GIF's 256-color palette, LZW compression, and small headers make it the only image format a 1993 web server can serve at scale and a 1993 browser can render before the user gives up. Video: An NCSA-era walkthrough of Mosaic sent to the US Copyright Office around 1994. Inline images, click-and-load.
- — The First Web GIF. An under construction bulldozer GIF, the genre of small decorative loop that defined the inline-image web the moment Mosaic shipped. Place: CERN, Geneva; early NCSA-adjacent academic web servers Figures: Robert Cailliau, co-author of the WWW proposal · various unnamed academic webmasters There is no canonical record of the first GIF embedded in an HTML page on the public web. The candidates are all from 1993, all academic, all small. Horizontal-rule decorations on early NCSA pages. The LE GROUPE iconography on Robert Cailliau's CERN homepage. NASA mission badges on JPL's earliest web server. A geological survey map on a USGS page that may or may not predate any of them. What is documented: by mid-1993, GIFs are appearing on dozens of academic web servers worldwide, all rendered inline by Mosaic (see [[mosaic-1993]]). The format moves from CompuServe-internal to web-public in a single quarter. The transition is not announced; it is observed in server logs. Video: info.cern.ch rendered inside NCSA Mosaic. The earliest web GIFs lived on academic servers exactly like this.
- — Unisys Enforces the LZW Patent. A flame GIF in the spirit of the Burn All GIFs campaign that the Unisys LZW enforcement announcement ignited in the week between Christmas and New Year 1994. Place: Unisys Corporation press release, Blue Bell, Pennsylvania Figures: Unisys legal department · the shareware authors who read CompuServe forums that week · Greg Roelofs and the nascent PNG working group Unisys, the merger-successor to Sperry, has owned the LZW patent (see [[lzw-patent-1985]]) since 1986. For eight years it does not enforce against GIF software. On 28 December 1994, in a press release timed for the week between Christmas and New Year, Unisys announces it will begin enforcing the patent against commercial software that creates or displays GIFs. The license fees: nominal for IBM and Adobe, ruinous for shareware authors charging $20 per copy. The announcement reaches the public web through CompuServe forum posts the same week, then through the comp.graphics Usenet groups, then through every webmaster mailing list. The reaction is immediate and uniform: PANIC, then ORGANIZED RESPONSE. Video: Stallman lays out the case against software patents using the LZW saga as one of his canonical examples.
- — AOL Passes CompuServe. A 1996 spinning globe GIF, the iconography of the dial up internet that AOL was selling to five million subscribers by the end of 1995. Place: Vienna, Virginia (AOL) and Columbus, Ohio (CompuServe) Figures: Steve Case, AOL CEO · H&R Block, CompuServe's parent company through 1998 · the millions of new AOL subscribers who never knew CompuServe invented the format Through the early 1990s, CompuServe is the dominant online service for technical users; AOL is the dominant service for everyone else. In 1994 they are roughly even at three million subscribers each. By the end of 1995, AOL has crossed five million and is growing faster than CompuServe can respond. The mass-market consumer modem demographic that AOL captures is the same demographic that, by 1996, is using Mosaic and Navigator on dial-up (see [[mosaic-1993]]) to view GIF-heavy web pages. The format CompuServe invented in 1987 is, by 1995, being used most heavily by AOL's much larger and faster-growing subscriber base. AOL ships its own software with built-in GIF support. The format's primary audience has, without fanfare, switched providers. Video: 1995 broadcast segment comparing the two dial-up services in the year AOL's subscriber count overtook CompuServe's.
- — The Netscape Loop Extension. A 22 frame looping butterfly, the type of infinite loop that the NETSCAPE2.0 application extension made the default behavior of every web GIF. Place: Netscape Communications, Mountain View, California Figures: Netscape Navigator 2.0 engineering team · the unnamed engineer who picked the bytes GIF89a (see [[gif89a-released-1989]]) allows multiple image frames in a single file, with per-frame delays. What it does not define is whether the sequence plays once and stops, or loops forever. Netscape's engineers, preparing Navigator 2.0 for release, need a default behavior and a way to override it. They use the format's application-extension-block mechanism to invent one. The bytes: 21 FF 0B NETSCAPE2.0 03 01 LOW HIGH 00. The application identifier is the literal ASCII string NETSCAPE2.0, eleven bytes long. The two-byte loop count is little-endian: 0000 means loop forever, any other value means loop exactly N times. Netscape Navigator 2.0 ships in December 1995 with this extension implemented. Every other browser follows. Video: Navigator 2.x, the build that first honored the NETSCAPE2.0 application extension and let GIFs loop forever.
- — PNG Released as W3C Recommendation. An under construction GIF, the late nineties aesthetic that PNG inherited a still image solution for while deferring animation to a spec that took two more decades. Place: World Wide Web Consortium, Cambridge, Massachusetts Figures: Thomas Boutell, working group chair · Glenn Randers-Pehrson, libpng author · Greg Roelofs, historian and documentation lead · Jean-loup Gailly, DEFLATE/zlib author PNG 1.0 ships as a W3C Recommendation on 1 October 1996, twenty-one months after the Unisys announcement (see [[unisys-enforcement-1994]]) made it necessary. The technical specification is, by every benchmark that matters, better than GIF: 24-bit true color instead of 8-bit palette, alpha transparency instead of single-bit transparency, DEFLATE compression patent-free instead of LZW, better lossless ratios on most image types. The format is designed by people who watched the Unisys ambush happen and are determined no future image standard will be hostage to a patent. The PNG specification includes explicit prior-art documentation for every algorithmic choice. The W3C process is fast for the era: from comp.graphics draft to Recommendation in twenty-one months.
