Documents Talking to Computers

By Amy Castor (for Xerox Corporation)

276_dataglyphsBar codes, used for years to encode data on paper, are ugly and hold a limited amount of information. Most contain simple serial numbers that link to detailed databases.

Answering the need for a more portable database, a technology called DataGlyph has been developed by Palo Alto Research Center (PARC), a subsidiary of Xerox Corporation. DataGlyphs stores hundreds of times more data than bar codes, making ordinary paper smarter. Better yet, DataGlyphs are aesthetically pleasing and “occlusion tolerant,” meaning that unlike bar codes, they can recreate themselves when damaged.

DataGlyphs encode information in thousands of tiny glyphs—diagonal lines that can be as short as 1/100th of an inch depending on the resolution of the printer. Each glyph slopes backward or forward to represent a binary 0 or 1. Glyphs are laid down in groups on a regular, finely spaced grid to form unobtrusive, evenly textured gray or colored areas. Even when groups of glyphs are large enough to be seen by the human eye, they form a pleasing pattern that is not distracting.

Anyone with the proper encoding software and a standard printer can create a DataGlyph, which can be treated as a standard design element or hidden in the corner of the document. Built-in error correction and randomization make DataGlyphs highly reliable and blur the line between the paper and digital world. If the information that is printed on a document is also encoded on it as a DataGlyph, the original document can be recovered even after it has been ripped, stained, or altered. Software code-named “GlyphSeals” reads the DataGlyphs on a scanned image of the page and can print the recovered data in its entirety. If more than 20 percent of the DataGlyph is missing or damaged, the software reports a decode failure.

Since DataGlyphs store the same types of information that a computer can, a paper document can become as powerful as software. In other words, all the electronic data for the document is encoded in the document itself. Beyond image and text, a DataGlyph can store Java or ActiveX controls for auto downloading applets onto a client PC. It can tell a server where to route a document or a printer what type of stationery to use. Equally as useful, if someone makes notes on a DataGlyph document, a computer can lift off the annotations and either store them separately or remove the mark-ups completely.

Future innovations to DataGlyph research will be in aesthetics. While some aspects of DataGlyph technology are already licensed and available for licensing, DataGlyph appearance is still undergoing improvements. The aim is to make them eventually invisible to the naked eye. Down the road a bit, for example, it may be DataGlyphs that ensure the integrity of the election ballots of the future.