The G3 facsimile standard was recently named an IEEE Milestone in Electrical and Computer Engineering. This key element in office-to-office communication, before the e-mail era, led to the fax transmittal standards in use today.
The idea of taking an image of a document and transmitting it over wires was first proposed back in 1843. Known as facsimile transmittal, or faxing for short, it began in 1865 between Paris and Lyon, France. But it wasn’t until the advent of the telephone—more than a decade later—that a widespread network of signal-carrying wires became available. In the 1920s technology (in the form of photoelectric cells) and need (in the form of photographs for newspapers) came together to create a small but important market for transmitting images.
By the late 1950s to early 1960s, there was sufficient interest from businesses and governments to transmit paperwork, telephone companies wanting to increase the use of their systems, and some electronic firms in making fax machines that a market for transmitting documents, not photographs, began.
The first commercial fax machines were expensive and used proprietary coding, which restricted their use to the few companies willing to buy multiple, compatible machines that could communicate only with one another. The first international facsimile standard in 1968, the so-called Group 1, broadened the machine’s appeal, but transmissions were still achingly slow—six minutes per page—and not all manufacturers followed the standard exactly.
More advanced standards became a research goal around the world, with strong backing from CCITT (the Consultative Committee International Telegraph and Telephone) and Japan’s Ministry of Posts and Telecommunications. Support was especially strong in Japan because the country’s complex writing system was hardly conducive to keyboard systems such as the Teletype. (Computers have since made Japanese keyboard entry more practical.) The Japanese alphabet, often considered to be the world’s most complicated, incorporates more than 2000 ideographic characters (kanji) based on Chinese and two 43-character syllabic character sets (kana). Using a fax machine, Japanese documents could be handwritten and transmitted easily.
That research led to the CCITT Group 2 standard, released in 1976. The G2 system was more closely adhered to by equipment makers, so fax users could be reasonably sure of compatible communications with users in other offices. And it was noticeably faster, at three minutes per page. The advancements led to a great increase in faxing—and to complaints that even G2’s faster transmission was too slow.
The breakthrough was a new system that could transmit a page in a minute or less. Jointly proposed and developed by KDD (Kokusai Denshin Denwa Co., now KDDI) and Nippon Telegraph and Telephone Public Corp. (now Nippon Telegraph and Telephone Corp., or NTT), the system used a two-dimensional digital coding system, modified READ (relative element address designate) that offered twice the compression performance of the then-standard modified Huffman coding. As with many new systems combining multiple companies’ technical developments, questions of intellectual property arose, but they were resolved when the Japanese delegates to a Kyoto meeting of CCITT offered the patents and property rights free of charge if the modified READ method was adopted as the international standard. That led to the adoption in 1980 of the Group 3 standard.
It also led to the MMR (modified MR) coding used in the G4 standard for faxing over digital networks, adopted four years later. Most fax machines today use the so-called Super G3 system, with enhanced speed, error correction, and gray-scale recognition.
A ceremony was held on 5 April to unveil the Milestone plaque, which was placed at the NTT Cyber Communications Laboratory Group in Yokosuka City, Kanagawa, Japan, where the system was developed. It reads:
International Standardization of G3 Facsimile, 1980
At this site, the two-dimensional coding MR (modified READ) method for G3 facsimile was developed through the careful collaboration of NTT and KDDI. It was the most innovative, efficient method, and was key to the success of international standardization. Strong Japanese leadership with intense international discussions and examinations yielded the G3 facsimile recommendation in 1980 to conclude international standardization efforts for redundancy-suppressing digital facsimile.