Prehistory
Before the format had a name: Sketchpad, MacPaint, Bezier curves, the conceptual ancestors of animated bitmap on a screen.
Part of GIfs
9 moments in this segment.
- — Sketchpad and the Light Pen. Lissajous figures tracing on a CRT. Sketchpad ran in 1963 on a 7-inch oscilloscope tube wired to the TX-2 mainframe. Place: MIT Lincoln Laboratory, Lexington, Massachusetts Figures: Ivan Sutherland, 24, doctoral candidate · Claude Shannon, thesis advisor · Marvin Minsky and Steven Coons, thesis committee · the TX-2 mainframe Ivan Sutherland defends his PhD thesis at MIT in January 1963. The artifact: Sketchpad, an interactive graphics program running on the TX-2 mainframe at Lincoln Lab. The user draws with a light pen directly on the CRT. The system snaps lines to constraints, infers rectangles from rough sketches, lets the artist define a master shape and instance it across the canvas. Object-oriented graphics, vector primitives, and constraint solvers all arrive in one 88,000-word document. The hardware is hardly portable. The TX-2 fills a room. The CRT is a 7-inch military-surplus oscilloscope tube. The light pen is wired with a thumb-switch. None of this matters. The interaction model, the artist pointing AT the image and the image responding, is the conceptual ancestor of every painting program, every CAD package, every photo editor, and every web-canvas tool that the next sixty years will produce. Video: The 1963 demonstration film of Ivan Sutherland's Sketchpad running on the TX-2 at MIT Lincoln Lab.
- — The Utah Teapot. A cubic Bezier curve constructing itself. Newell built the Utah teapot from 32 bicubic Bezier patches in 1975. Place: University of Utah Computer Graphics Lab, Salt Lake City Figures: Martin Newell, graduate researcher · Sandra Newell, his wife, who suggested the teapot over afternoon tea · Jim Blinn, Ed Catmull, and the Utah graphics cohort Martin Newell needs a test object for his rendering research at Utah. The object has to be familiar (so rendering errors are obvious), mathematically interesting (curvature, handle, spout, lid), and small enough that the geometry fits in 1975-era memory. His wife Sandra suggests the Melitta teapot on their kitchen table. He sketches it on graph paper, measures the control points by eye, and encodes it as 32 bicubic Bezier patches. The teapot, modeled in an afternoon, has the perfect surface topology for testing: a hole through the handle, a non-convex spout, a flat lid that catches light differently than the curved body, a base that demonstrates shadow accuracy. It is, by accident, the most pedagogically useful test object computer graphics has ever had. The original physical teapot now sits in the Computer History Museum in Mountain View. Video: Tom Scott visits the Computer History Museum to tell the story of Martin Newell's 1975 reference object.
- — Scott Fahlman Proposes :-). Smiling eyes, blinking mouth. Scott Fahlman's :-) gets a moving descendant decades later. Place: Carnegie Mellon University Computer Science bboard, Pittsburgh Figures: Scott Fahlman, research professor · the CMU CS faculty and graduate students reading the cs.general bboard The CMU computer science department runs an internal bulletin-board system. Recent threads have been getting derailed because nobody can tell which posts are jokes. On 19 September 1982 at 11:44 a.m., Scott Fahlman posts a 19-line message proposing a solution. The full text:I propose that the following character sequence for joke markers::-)Read it sideways. Actually, it is probably more economical to mark things that are NOT jokes, given current trends. For this, use:-(The post is read by a few dozen CMU researchers. It propagates from CMU to Bell Labs, Xerox PARC, and the early ARPAnet within months. By the late 1980s the emoticon is a standard component of email and Usenet etiquette. Video: Scott Fahlman, in his own words, on the 11:44 a.m. CMU bulletin-board post that proposed :-) in 1982.
- — MacPaint Ships. A pixel-art monster drawn frame by frame. MacPaint, shipped January 1984, made this kind of bitmap painting consumer software. Place: Apple Computer, Cupertino, California Figures: Bill Atkinson, lead developer · Susan Kare, icon and pattern designer · the original Macintosh team 24 January 1984. Steve Jobs unveils the Macintosh at the Flint Center in Cupertino. The 128K machine ships with two applications in the box: MacWrite and MacPaint. MacPaint is Bill Atkinson's, written in roughly 5,800 lines of Pascal and 2,700 lines of 68000 assembly. The canvas is 576x720, one bit per pixel, pure black-and-white. There is a brush palette, a fill bucket, a lasso, a marquee selector, and eight patterns designed by Susan Kare. The interaction model is descended directly from Sketchpad (see [[sketchpad-1963]]) but stripped to consumer simplicity. A child can use it. By the end of 1984, hundreds of thousands of Macintosh owners have produced bitmap images. The medium has, for the first time, a mass amateur production base. The PICT format that MacPaint saves to is the first consumer image format with real adoption. Video: Bill Atkinson and Andy Hertzfeld walk through MacPaint at the Computer History Museum.
- — ANSI Art and the BBS Scene. Glitched pixels scrolling past. The visual descendants of ANSI block characters lighting up dial-up BBS screens. Place: The worldwide BBS scene; ACiD Productions, iCE Advertisements, the warez and demo BBSes Figures: RaD Man, co-founder of ACiD Productions (1990, with Shadow Demon, Grimm, The Beholder, Phantom) · Many Axe (later Frozen Tormentor), founder of iCE (1991, founded in Canada) · the artist scenes of Toronto, Montreal, Detroit, the European 4-color cracker boards The IBM PC ships with Code Page 437, an extended ASCII set that includes block characters (▀ ▄ █ ░ ▒ ▓), box-drawing characters (─ │ ┌ ┐ └ ┘ ╔ ╗), and assorted geometric primitives. Combine those 256 glyphs with the PC's 16 text-mode colors, drop them on an 80x25 character grid, and you have a working image format that transmits over a 1200-baud line in about three seconds. The image is the screen. By 1984 every serious BBS has an opening screen done in ANSI. ACiD Productions (1990) and iCE Advertisements (1991) formalize the scene as competing art groups, releasing monthly art packs distributed via the boards themselves. Some pieces are loading-screen ads for warez BBSes; some are gallery pieces with no commercial purpose. Resolution: 80x25. Palette: 16. File extension: .ANS. Some of the best of it survives in archive.org's textfiles.com mirror. Video: Jason Scott's ARTSCENE episode tells the history of the ANSI art crews who turned Code Page 437 into a scene.
- — Barnsley's Fractal Compression. The Barnsley fern assembling under iterated function system rules. Barnsley's 1985 papers proposed compressing the equation instead of the pixels. Place: Georgia Institute of Technology, Atlanta; later Iterated Systems Inc., Norcross, Georgia Figures: Michael Barnsley, mathematician · Alan Sloan, co-founder of Iterated Systems · the IFS (iterated function system) research community Michael Barnsley publishes the Collage Theorem in 1985. The idea: any image can be approximated as the fixed point of a contractive iterated function system, a small set of affine transformations that, applied recursively, converge to the original picture. Store the transformations, throw away the pixels. The compression ratios on suitable imagery are spectacular, sometimes 100-to-1 or better. The Sierpinski triangle compresses to four numbers. A fern compresses to twenty-eight. Barnsley and Alan Sloan found Iterated Systems in 1987 to commercialize the idea. The encoder, which has to FIND the contractive transformations, is wildly expensive (hours per image on 1980s hardware). The decoder is fast and resolution-independent: the same compressed file renders at any output size. It is, on paper, the ideal format for the bandwidth-constrained future. Video: The chaos game and Barnsley fern, the iterated function systems behind Michael Barnsley's 1985 compression idea.
- — PCX, the IBM PC Bitmap. Vaporwave paint loop. ZSoft PC Paintbrush ships the PCX format and teaches DOS to draw. Place: ZSoft Corporation, Marietta, Georgia Figures: ZSoft engineering team · the PC Paintbrush user base ZSoft ships PC Paintbrush for the IBM PC in 1985. The companion file format, PCX (PC Paintbrush eXchange), is purpose-built for the program: header, palette, raster data, RLE-compressed run by run. Simple enough that a competent C programmer can write a decoder in an afternoon. By 1988 PCX is the dominant bitmap format on MS-DOS, supported by every PC paint program, every screen-capture utility, and every fax driver of the era. The compression is run-length encoding: a byte indicating how many consecutive pixels share a color, then the color. On screenshots and line art the ratios are excellent. On photographic or dithered imagery they are catastrophic; a typical PCX of a scanned photograph is LARGER than the raw bitmap. The format never solves this. RLE has a ceiling that LZW (see [[lzw-patent-1985]]) does not. Video: LGR traces the line from ZSoft PC Paintbrush and its PCX format through every Microsoft Paint revision.
- — The LZW Patent. Handcuffs and paperclips. Unisys patents LZW compression and quietly arms the lawsuit clock. Place: Sperry Corporation (later Unisys), patent USPTO 4,558,302 Figures: Terry Welch, author of the 1984 Communications of the ACM paper on LZ-Welch compression Terry Welch publishes A Technique for High-Performance Data Compression in IEEE Computer in June 1984. The paper describes a variant of Lempel-Ziv that uses a dictionary built on the fly during compression, so the decompressor can reconstruct the dictionary without it being sent. The compression ratios are excellent on the kind of repetitive bitmap data computer graphics produce. Sperry Corporation files for a patent. USPTO 4,558,302 issues on 10 December 1985 to Sperry. By the time CompuServe ships the GIF format two years later (see [[compuserve-ships-gif87a-1987]]), LZW is the only commercially-viable compression algorithm for the image data the format needs to carry. The format and the patent travel together for the next fifteen years. Video: Professor Brailsford explains the Lempel and Ziv dictionary lineage that Terry Welch's 1984 paper extended into LZW.
- — TIFF, the Prepress Format. Inkjet doing its thing. Aldus releases TIFF so desktop publishers can move pages between scanners and printers. Place: Aldus Corporation, Seattle, Washington Figures: Aldus engineering team · the desktop-publishing vendor consortium · Adobe (post-1994 acquirer of Aldus and steward of the spec) Aldus Corporation, maker of PageMaker, releases Tagged Image File Format revision 3.0 in 1986. The brief: a single format that scanner vendors, prepress houses, color-separation services, and the new desktop-publishing software can all agree on. The solution is structural. A TIFF file is a header followed by an arbitrary number of image file directories, each containing tagged fields (resolution, color depth, compression, photometric interpretation, calibration data) and pointing at a strip or tile of raster data. The format supports 1-bit, 8-bit, 24-bit, 48-bit, multi-channel. CMYK. Lab. ICC color profiles. LZW was added in TIFF Revision 5.0 (October 1988), NOT in 6.0 (1992). JPEG was added in 6.0 (June 1992). Multiple images per file, multiple resolutions per image. It is, by 1992, the most powerful raster format in existence. A standard PageMaker workflow can produce TIFFs that are hundreds of megabytes.
