Fax

Fax (short for facsimile), sometimes called telecopying or telefax (the latter short for telefacsimile), is the telephonic transmission of scanned printed material (both text and images), normally to a telephone number connected to a printer or other output device. The original document is scanned with a fax machine (or a telecopier), which processes the contents (text or images) as a single fixed graphic image, converting it into a bitmap, and then transmitting it through the telephone system in the form of audio-frequency tones. The receiving fax machine interprets the tones and reconstructs the image, printing a paper copy.[1] Early systems used direct conversions of image darkness to audio tone in a continuous or analog manner. Since the 1980s, most machines modulate the transmitted audio frequencies using a digital representation of the page which is compressed to quickly transmit areas which are all-white or all-black.

Samfax
A fax machine from the late 1990s

History

Wire transmission

Scottish inventor Alexander Bain worked on chemical mechanical fax type devices and in 1846 was able to reproduce graphic signs in laboratory experiments. He received British patent 9745 on May 27, 1843 for his "Electric Printing Telegraph".[2]

Frederick Bakewell made several improvements on Bain's design and demonstrated a telefax machine. The Pantelegraph was invented by the Italian physicist Giovanni Caselli. He introduced the first commercial telefax service between Paris and Lyon in 1865, some 11 years before the invention of the telephone.[3][4]

In 1880, English inventor Shelford Bidwell constructed the scanning phototelegraph that was the first telefax machine to scan any two-dimensional original, not requiring manual plotting or drawing. Around 1900, German physicist Arthur Korn invented the Bildtelegraph, widespread in continental Europe especially, since a widely noticed transmission of a wanted-person photograph from Paris to London in 1908, used until the wider distribution of the radiofax. Its main competitors were the Bélinographe by Édouard Belin first, then since the 1930s the Hellschreiber, invented in 1929 by German inventor Rudolf Hell, a pioneer in mechanical image scanning and transmission.

The 1888 invention of the telautograph by Elisha Gray marked a further development in fax technology, allowing users to send signatures over long distances, thus allowing the verification of identification or ownership over long distances.[5]

On May 19, 1924, scientists of the AT&T Corporation "by a new process of transmitting pictures by electricity" sent 15 photographs by telephone from Cleveland to New York City, such photos being suitable for newspaper reproduction. Previously, photographs had been sent over the radio using this process.[6]

The Western Union "Deskfax" fax machine, announced in 1948, was a compact machine that fit comfortably on a desktop, using special spark printer paper.[7]

Wireless transmission

Krant per fax - Faxed newspaper (4193509648)
Children read a wirelessly-transmitted newspaper in 1938.

As a designer for the Radio Corporation of America (RCA), in 1924, Richard H. Ranger invented the wireless photoradiogram, or transoceanic radio facsimile, the forerunner of today’s "fax" machines. A photograph of President Calvin Coolidge sent from New York to London on November 29, 1924, became the first photo picture reproduced by transoceanic radio facsimile. Commercial use of Ranger’s product began two years later. Also in 1924, Herbert E. Ives of AT&T transmitted and reconstructed the first color facsimile, a natural-color photograph of silent film star Rudolph Valentino in period costume, using red, green and blue color separations.[8]

Beginning in the late 1930s, the Finch Facsimile system was used to transmit a "radio newspaper" to private homes via commercial AM radio stations and ordinary radio receivers equipped with Finch's printer, which used thermal paper. Sensing a new and potentially golden opportunity, competitors soon entered the field, but the printer and special paper were expensive luxuries, AM radio transmission was very slow and vulnerable to static, and the newspaper was too small. After more than ten years of repeated attempts by Finch and others to establish such a service as a viable business, the public, apparently quite content with its cheaper and much more substantial home-delivered daily newspapers, and with conventional spoken radio bulletins to provide any "hot" news, still showed only a passing curiosity about the new medium.[9]

By the late 1940s, radiofax receivers were sufficiently miniaturized to be fitted beneath the dashboard of Western Union's "Telecar" telegram delivery vehicles.[7]

In the 1960s, the United States Army transmitted the first photograph via satellite facsimile to Puerto Rico from the Deal Test Site using the Courier satellite.

Radio fax is still in limited use today for transmitting weather charts and information to ships at sea. Also, it is also widely used within the medical field to transmit confidential patient information.

Telephone transmission

In 1964, Xerox Corporation introduced (and patented) what many consider to be the first commercialized version of the modern fax machine, under the name (LDX) or Long Distance Xerography. This model was superseded two years later with a unit that would truly set the standard for fax machines for years to come. Up until this point facsimile machines were very expensive and hard to operate. In 1966, Xerox released the Magnafax Telecopiers, a smaller, 46-pound facsimile machine. This unit was far easier to operate and could be connected to any standard telephone line. This machine was capable of transmitting a letter-sized document in about six minutes. The first sub-minute, digital fax machine was developed by Dacom, which built on digital data compression technology originally developed at Lockheed for satellite communication.[10][11]

By the late 1970s, many companies around the world (especially Japanese firms) had entered the fax market. Very shortly after this, a new wave of more compact, faster and efficient fax machines would hit the market. Xerox continued to refine the fax machine for years after their ground-breaking first machine. In later years it would be combined with copier equipment to create the hybrid machines we have today that copy, scan and fax. Some of the lesser known capabilities of the Xerox fax technologies included their Ethernet enabled Fax Services on their 8000 workstations in the early 1980s.

Prior to the introduction of the ubiquitous fax machine, one of the first being the Exxon Qwip[12] in the mid-1970s, facsimile machines worked by optical scanning of a document or drawing spinning on a drum. The reflected light, varying in intensity according to the light and dark areas of the document, was focused on a photocell so that the current in a circuit varied with the amount of light. This current was used to control a tone generator (a modulator), the current determining the frequency of the tone produced. This audio tone was then transmitted using an acoustic coupler (a speaker, in this case) attached to the microphone of a common telephone handset. At the receiving end, a handset’s speaker was attached to an acoustic coupler (a microphone), and a demodulator converted the varying tone into a variable current that controlled the mechanical movement of a pen or pencil to reproduce the image on a blank sheet of paper on an identical drum rotating at the same rate.

Computer facsimile interface

In 1985, Hank Magnuski, founder of GammaLink, produced the first computer fax board, called GammaFax. Such boards could provide voice telephony via Analog Expansion Bus.[13]

Fax in the 21st century

Although businesses usually maintain some kind of fax capability, the technology has faced increasing competition from Internet-based alternatives. In some countries, because electronic signatures on contracts are not yet recognized by law, while faxed contracts with copies of signatures are, fax machines enjoy continuing support in business.[14] In Japan, faxes are still used extensively for cultural and graphemic reasons and are available for sending to both domestic and international recipients from over 81% of all convenience stores nationwide. Convenience-store fax machines commonly print the slightly re-sized content of the sent fax in the electronic confirmation-slip, in A4 paper size.[15][16][17]

In many corporate environments, freestanding fax machines have been replaced by fax servers and other computerized systems capable of receiving and storing incoming faxes electronically, and then routing them to users on paper or via an email (which may be secured). Such systems have the advantage of reducing costs by eliminating unnecessary printouts and reducing the number of inbound analog phone lines needed by an office.

The once ubiquitous fax machine has also begun to disappear from the small office and home office environments. Remotely hosted fax-server services are widely available from VoIP and e-mail providers allowing users to send and receive faxes using their existing e-mail accounts without the need for any hardware or dedicated fax lines. Personal computers have also long been able to handle incoming and outgoing faxes using analog modems or ISDN, eliminating the need for a stand-alone fax machine. These solutions are often ideally suited for users who only very occasionally need to use fax services. In July 2017 the United Kingdom's National Health Service was said to be the world's largest purchaser of fax machines because the digital revolution has largely bypassed it.[18] In June 2018 the Labour Party said that the NHS had at least 11,620 fax machines in operation[19] and in December the Department of Health and Social Care said that no more fax machines could be bought from 2019 and that the existing ones must be replaced by secure email by 31 March 2020.[20]

Leeds Teaching Hospitals NHS Trust, generally viewed as digitally advanced in the NHS, was engaged in a process of removing its fax machines in early 2019. This involved quite a lot of e-fax solutions because of the need to communicate with pharmacies and nursing homes which may not have access to the NHS email system and may need something in their paper records.[21]

In 2018 two-thirds of Canadian doctors reported that they primarily used fax machines to communicate with other doctors. Faxes are seen, probably mistakenly, as safer and more secure and electronic systems are often unable to communicate with each other.[22]

Capabilities

There are several indicators of fax capabilities: group, class, data transmission rate, and conformance with ITU-T (formerly CCITT) recommendations. Since the 1968 Carterphone decision, most fax machines have been designed to connect to standard PSTN lines and telephone numbers.

Group

Analog

Group 1 and 2 faxes are sent in the same manner as a frame of analog television, with each scanned line transmitted as a continuous analog signal. Horizontal resolution depended upon the quality of the scanner, transmission line, and the printer. Analog fax machines are obsolete and no longer manufactured. ITU-T Recommendations T.2 and T.3 were withdrawn as obsolete in July 1996.

  • Group 1 faxes conform to the ITU-T Recommendation T.2. Group 1 faxes take six minutes to transmit a single page, with a vertical resolution of 96 scan lines per inch. Group 1 fax machines are obsolete and no longer manufactured.
  • Group 2 faxes conform to the ITU-T Recommendations T.3 and T.30. Group 2 faxes take three minutes to transmit a single page, with a vertical resolution of 96 scan lines per inch. Group 2 fax machines are almost obsolete, and are no longer manufactured. Group 2 fax machines can interoperate with Group 3 fax machines.

Digital

Dacom DFC-10
The Dacom DFC-10—the first digital fax machine.[10]
Faxchip
The chip in a fax machine. Only about one quarter of the length is shown. The thin line in the middle consists of photosensitive pixels. The read-out circuit is at left.
MN8051 Matsushita CCD side+ cm
CCD MN8051 Matsushita CCD side, monochrome 2048-bit linear sensor +cm (centimeters)

A major breakthrough in the development of the modern facsimile system was the result of digital technology, where the analog signal from scanners was digitized and then compressed, resulting in the ability to transmit high rates of data across standard phone lines. The first digital fax machine was the Dacom Rapidfax first sold in late 1960s, which incorporated digital data compression technology developed by Lockheed for transmission of images from satellites.[10][11]

Group 3 and 4 faxes are digital formats, and take advantage of digital compression methods to greatly reduce transmission times.

  • Group 3 faxes conform to the ITU-T Recommendations T.30 and T.4. Group 3 faxes take between six and fifteen seconds to transmit a single page (not including the initial time for the fax machines to handshake and synchronize). The horizontal and vertical resolutions are allowed by the T.4 standard to vary among a set of fixed resolutions:
    • Horizontal: 100 scan lines per inch
      • Vertical: 100 scan lines per inch ("Basic")
    • Horizontal: 200 or 204 scan lines per inch
      • Vertical: 100 or 98 scan lines per inch ("Standard")
      • Vertical: 200 or 196 scan lines per inch ("Fine")
      • Vertical: 400 or 391 (note not 392) scan lines per inch ("Superfine")
    • Horizontal: 300 scan lines per inch
      • Vertical: 300 scan lines per inch
    • Horizontal: 400 or 408 scan lines per inch
      • Vertical: 400 or 391 scan lines per inch ("Ultrafine")
  • Group 4 faxes conform to the ITU-T Recommendations T.563, T.503, T.521, T.6, T.62, T.70, T.411 to T.417. They are designed to operate over 64 kbit/s digital ISDN circuits. The allowed resolutions, a superset of those in the T.4 recommendation, are specified in the T.6 recommendation.[23]

Fax Over IP (FoIP) can transmit and receive pre-digitized documents at near realtime speeds using ITU-T recommendation T.38 to send digitised images over an IP network using JPEG compression. T.38 is designed to work with VoIP services and often supported by analog telephone adapters used by legacy fax machines that need to connect through a VoIP service. Scanned documents are limited to the amount of time the user takes to load the document in a scanner and for the device to process a digital file. The resolution can vary from as little as 150 DPI to 9600 DPI or more. This type of faxing is not related to the e-mail to fax service that still uses fax modems at least one way.

Class

Computer modems are often designated by a particular fax class, which indicates how much processing is offloaded from the computer's CPU to the fax modem.

  • Class 1 (also known as Class 1.0) fax devices do fax data transfer where the T.4/T.6 data compression and T.30 session management are performed by software on a controlling computer. This is described in ITU-T recommendation T.31.[24]
  • What is commonly known as "Class 2" is an unofficial class of fax devices that perform T.30 session management themselves, but the T.4/T.6 data compression is performed by software on a controlling computer. Implementations of this "class" are based on draft versions of the standard that eventually significantly evolved to become Class 2.0.[25] All implementations of "Class 2" are manufacturer-specific.[26]
  • Class 2.0 is the official ITU-T version of Class 2, and is commonly known as Class 2.0 to differentiate it from many manufacturer-specific implementations of what is commonly known as "Class 2". It uses a different but standardized command set than the various manufacturer-specific implementations of "Class 2". The relevant ITU-T recommendation is T.32.[26]
  • Class 2.1 is an improvement of Class 2.0 that implements faxing over V.34 (33.6 kbps), which boosts faxing speed from fax classes "2" and 2.0 which are limited to 14.4 kbps.[26] The relevant ITU-T recommendation is T.32 Amendment 1.[26] Class 2.1 fax devices are referred to as "super G3".

Data transmission rate

Several different telephone line modulation techniques are used by fax machines. They are negotiated during the fax-modem handshake, and the fax devices will use the highest data rate that both fax devices support, usually a minimum of 14.4 kbit/s for Group 3 fax.

ITU Standard Released Date Data Rates (bit/s) Modulation Method
V.27 1988 4800, 2400 PSK
V.29 1988 9600, 7200, 4800 QAM
V.17 1991 14,400; 12,000; 9600; 7200 TCM
V.34 1994 28,800 QAM
V.34bis 1998 33,600 QAM
ISDN 1986 64,000 digital

Note that "Super Group 3" faxes use V.34bis modulation that allows a data rate of up to 33.6 kbit/s.

Compression

As well as specifying the resolution (and allowable physical size of the image being faxed), the ITU-T T.4 recommendation specifies two compression methods for decreasing the amount of data that needs to be transmitted between the fax machines to transfer the image. The two methods defined in T.4 are:[27]

An additional method is specified in T.6:[23]

Later, other compression techniques were added as options to ITU-T recommendation T.30, such as the more efficient JBIG (T.82, T.85) for bi-level content, and JPEG (T.81), T.43, MRC (T.44), and T.45 for grayscale, palette, and colour content.[29] Fax machines can negotiate at the start of the T.30 session to use the best technique implemented on both sides.

Modified Huffman

Modified Huffman (MH), specified in T.4 as the one-dimensional coding scheme, is a codebook-based run-length encoding scheme optimised to efficiently compress whitespace.[27] As most faxes consist mostly of white space, this minimises the transmission time of most faxes. Each line scanned is compressed independently of its predecessor and successor.[27]

Modified READ

Modified READ, specified as an optional two-dimensional coding scheme in T.4, encodes the first scanned line using MH.[27] The next line is compared to the first, the differences determined, and then the differences are encoded and transmitted.[27] This is effective as most lines differ little from their predecessor. This is not continued to the end of the fax transmission, but only for a limited number of lines until the process is reset and a new 'first line' encoded with MH is produced. This limited number of lines is to prevent errors propagating throughout the whole fax, as the standard does not provide for error-correction. This is an optional facility, and some fax machines do not use MR in order to minimise the amount of computation required by the machine. The limited number of lines is two for 'Standard' resolution faxes, and four for 'Fine' resolution faxes.

Modified Modified READ

The ITU-T T.6 recommendation adds a further compression type of Modified Modified READ (MMR), which simply allows for a greater number of lines to be coded by MR than in T.4.[23] This is because T.6 makes the assumption that the transmission is over a circuit with a low number of line errors such as digital ISDN. In this case, there is no maximum number of lines for which the differences are encoded.

JBIG

In 1999, ITU-T recommendation T.30 added JBIG (ITU-T T.82) as another lossless bi-level compression algorithm, or more precisely a "fax profile" subset of JBIG (ITU-T T.85). JBIG-compressed pages result in 20% to 50% faster transmission than MMR-compressed pages, and up to 30-times faster transmission if the page includes halftone images.

JBIG performs adaptive compression, that is both the encoder and decoder collect statistical information about the transmitted image from the pixels transmitted so far, in order to predict the probability for each next pixel being either black or white. For each new pixel, JBIG looks at ten nearby, previously transmitted pixels. It counts, how often in the past the next pixel has been black or white in the same neighborhood, and estimates from that the probability distribution of the next pixel. This is fed into an arithmetic coder, which adds only a small fraction of a bit to the output sequence if the more probable pixel is then encountered.

The ITU-T T.85 "fax profile" constrains some optional features of the full JBIG standard, such that codecs do not have to keep data about more than the last three pixel rows of an image in memory at any time. This allows the streaming of "endless" images, where the height of the image may not be known until the last row is transmitted.

ITU-T T.30 allows fax machines to negotiate one of two options of the T.85 "fax profile":

  • In "basic mode", the JBIG encoder must split the image into horizontal stripes of 128 lines (parameter L0=128), and restart the arithmetic encoder for each stripe.
  • In "option mode", there is no such constraint.

Matsushita Whiteline Skip

A proprietary compression scheme employed on Panasonic fax machines is Matsushita Whiteline Skip (MWS). It can be overlaid on the other compression schemes, but is operative only when two Panasonic machines are communicating with one another. This system detects the blank scanned areas between lines of text, and then compresses several blank scan lines into the data space of a single character. (JBIG implements a similar technique called "typical prediction", if header flag TPBON is set to 1.)

Typical characteristics

Group 3 fax machines transfer one or a few printed or handwritten pages per minute in black-and-white (bitonal) at a resolution of 204×98 (normal) or 204×196 (fine) dots per square inch. The transfer rate is 14.4 kbit/s or higher for modems and some fax machines, but fax machines support speeds beginning with 2400 bit/s and typically operate at 9600 bit/s. The transferred image formats are called ITU-T (formerly CCITT) fax group 3 or 4. Group 3 faxes have the suffix .g3 and the MIME type image/g3fax.

The most basic fax mode transfers in black and white only. The original page is scanned in a resolution of 1728 pixels/line and 1145 lines/page (for A4). The resulting raw data is compressed using a modified Huffman code optimized for written text, achieving average compression factors of around 20. Typically a page needs 10 s for transmission, instead of about 3 minutes for the same uncompressed raw data of 1728×1145 bits at a speed of 9600 bit/s. The compression method uses a Huffman codebook for run lengths of black and white runs in a single scanned line, and it can also use the fact that two adjacent scanlines are usually quite similar, saving bandwidth by encoding only the differences.

Fax classes denote the way fax programs interact with fax hardware. Available classes include Class 1, Class 2, Class 2.0 and 2.1, and Intel CAS. Many modems support at least class 1 and often either Class 2 or Class 2.0. Which is preferable to use depends on factors such as hardware, software, modem firmware, and expected use.

Printing process

Fax machines from the 1970s to the 1990s often used direct thermal printers with rolls of thermal paper as their printing technology, but since the mid-1990s there has been a transition towards plain-paper faxes: thermal transfer printers, inkjet printers and laser printers.

One of the advantages of inkjet printing is that inkjets can affordably print in color; therefore, many of the inkjet-based fax machines claim to have color fax capability. There is a standard called ITU-T30e (formally ITU-T Recommendation T.30 Annex E [30]) for faxing in color; however, it is not widely supported, so many of the color fax machines can only fax in color to machines from the same manufacturer.

Stroke speed

Stroke speed in facsimile systems is the rate at which a fixed line perpendicular to the direction of scanning is crossed in one direction by a scanning or recording spot. Stroke speed is usually expressed as a number of strokes per minute. When the fax system scans in both directions, the stroke speed is twice this number. In most conventional 20th century mechanical systems, the stroke speed is equivalent to drum speed.[31]

Fax paper

ThermalPaperG3-TMG
Paper roll for direct thermal fax machine

As a precaution, thermal fax paper is typically not accepted in archives or as documentary evidence in some courts of law unless photocopied. This is because the image-forming coating is eradicable and brittle, and it tends to detach from the medium after a long time in storage.[32]

Internet fax

One popular alternative is to subscribe to an Internet fax service, allowing users to send and receive faxes from their personal computers using an existing email account. No software, fax server or fax machine is needed. Faxes are received as attached TIFF or PDF files, or in proprietary formats that require the use of the service provider's software. Faxes can be sent or retrieved from anywhere at any time that a user can get Internet access. Some services offer secure faxing to comply with stringent HIPAA and Gramm–Leach–Bliley Act requirements to keep medical information and financial information private and secure. Utilizing a fax service provider does not require paper, a dedicated fax line, or consumable resources.[33]

Another alternative to a physical fax machine is to make use of computer software which allows people to send and receive faxes using their own computers, utilizing fax servers and unified messaging. A virtual (email) fax can be printed out and then signed and scanned back to computer before being emailed. Also the sender can attach a digital signature to the document file.

With the surging popularity of mobile phones, virtual fax machines can now be downloaded as applications for Android and iOS. These applications make use of the phone's internal camera to scan fax documents for upload or they can import from various cloud services.

Related standards

  • T.4 is the umbrella specification for fax. It specifies the standard image sizes, two forms of image-data compression (encoding), the image-data format, and references, T.30 and the various modem standards.
  • T.6 specifies a compression scheme that reduces the time required to transmit an image by roughly 50-percent.
  • T.30 specifies the procedures that a sending and receiving terminal use to set up a fax call, determine the image size, encoding, and transfer speed, the demarcation between pages, and the termination of the call. T.30 also references the various modem standards.
  • V.21, V.27ter, V.29, V.17, V.34: ITU modem standards used in facsimile. The first three were ratified prior to 1980, and were specified in the original T.4 and T.30 standards. V.34 was published for fax in 1994.[34]
  • T.37 The ITU standard for sending a fax-image file via e-mail to the intended recipient of a fax.
  • T.38 The ITU standard for sending Fax over IP (FoIP).
  • G.711 pass through - this is where the T.30 fax call is carried in a VoIP call encoded as audio. This is sensitive to network packet loss, jitter and clock synchronization. When using voice high-compression encoding techniques such as, but not limited to, G.729, some fax tonal signals may not get correctly transported across the packet network.
  • RFC 3362 image/t38 MIME-type

See also

References

  1. ^ Rouse, Margaret (June 2006). "What is fax?". SearchNetworking. Retrieved 25 July 2012.
  2. ^ “Mr. Bain’s Electric Printing Telegraph,” Mechanics' Magazine April 13, 1844, 268–70
  3. ^ "Istituto Tecnico Industriale, Italy. Italian biography of Giovanni Caselli". Itisgalileiroma.it. Retrieved 2014-02-16.
  4. ^ The Hebrew University of Jerusalem – Giovanni Caselli biography Archived May 6, 2008, at the Wayback Machine
  5. ^ "The History of Fax – from 1843 to Present Day". Fax Authority. Retrieved 25 July 2012.
  6. ^ The Montreal Gazette, May 20, 1924, page 10, column 3
  7. ^ a b G. H. Ridings, A Facsimile transceiver for Pickup and Delivery of Telegrams, Western Union Technical Review, Vol. 3, No, 1 (January 1949); page 17-26.
  8. ^ Sipley, Louis Walton (1951). A Half Century of Color. Macmillan.
  9. ^ Schneider, John (2011). "The Newspaper of the Air: Early Experiments with Radio Facsimile". theradiohistorian.org. Retrieved 2017-05-15.
  10. ^ a b c The implementation of a personal computer-based digital facsimile information distribution system – Edward C. Chung, Ohio University, November 1991, page 2
  11. ^ a b Fax: The Principles and Practice of Facsimile Communication, Daniel M. Costigan, Chilton Book Company, 1971, pages 112–114, 213, 239
  12. ^ An Exxon Sale To Harris UnitThe New York Times, February 22, 1985.
  13. ^ Perratore, Ed (September 1992). "GammaFax MLCP-4/AEB: High-End Fax, Long-Range Potential". Byte. Vol. 17 no. 9. McGraw-Hill. pp. 82, 84. ISSN 0360-5280.
  14. ^ Adams, Ken (7 November 2007). "Enforceability of Fax and Scanned Signature Pages". AdamsDrafting. Retrieved 25 July 2012.
  15. ^ "FAXサービス|サービス|ローソン" (in Japanese). Archived from the original on 2015-02-10.
  16. ^ Fackler, Martin (13 February 2013). "In High-Tech Japan, the Fax Machines Roll On". The New York Times. Retrieved 14 February 2013.
  17. ^ Oi, Mariko (2012-07-31). "BBC News – Japan and the fax: A love affair". Bbc.co.uk. Retrieved 2014-02-16.
  18. ^ "Digital doldrums: NHS remains world's largest purchaser of fax machines". National Health Executive. 5 July 2017. Retrieved 1 March 2018.
  19. ^ "NHS 'Struggling To Keep Up' As It Holds On To Thousands Of Fax Machines". Huffington Post. 11 June 2018. Retrieved 11 June 2018.
  20. ^ "NHS told to ditch 'absurd' fax machines". BBC. 9 December 2018. Retrieved 9 December 2018.
  21. ^ "OK, it's early 2019. Has Leeds Hospital finally managed to 'axe the fax'? Um, yes and no". The Register. 4 February 2019. Retrieved 5 February 2019.
  22. ^ "Why are fax machines still the norm in 21st-century health care?". Globe and Mail. 11 June 2018. Retrieved 21 April 2019.
  23. ^ a b c "T.6: Facsimile coding schemes and coding control functions for Group 4 facsimile apparatus". ITU-T. November 1988. Retrieved 2013-12-28.
  24. ^ Peterson, Kerstin Day (2000). Business telecom systems: a guide to choosing the best technologies and services. Focal Press. pp. 191–192. ISBN 1578200415. Retrieved 2011-04-02.
  25. ^ "Supra Technical Support Bulletin: Class 2 Fax Commands For Supra Faxmodems". June 19, 1992. Retrieved March 23, 2019.
  26. ^ a b c d "Fax Developer's Guide: Classes 2 and 2.0/2.1" (PDF). Multi-Tech Systems. 2017. Retrieved March 23, 2019.
  27. ^ a b c d e "T.4: Standardization of Group 3 facsimile terminals for document transmission". ITU-T. 2011-03-14. Retrieved 2013-12-28.
  28. ^ International digital facsimile coding standards, Hunter, R., and Robinson, A.H., Proceedings of the IEEE Volume 68 Issue 7, pp 854–867, July 1980
  29. ^ "T.30: Procedures for document facsimile transmission in the general switched telephone network". ITU-T. 2014-05-15. Retrieved 2013-12-28.
  30. ^ tsbmail. "T.30 : Procedures for document facsimile transmission in the general switched telephone network". Itu.int. Retrieved 2014-02-16.
  31. ^  This article incorporates public domain material from the General Services Administration document "Federal Standard 1037C" (in support of MIL-STD-188).
  32. ^ "4.12 Filing rules: 19.Newspaper extracts or thermal facsimile paper should not be preserved as archives. Such extracts should be photocopied and the copy preserved. The original can then be destroyed." Office of Corporate & Legal Affairs, University College Cork, Ireland
  33. ^ "Online Fax vs Traditional Fax". eFax. 16 May 2013. Retrieved 8 December 2013.
  34. ^ "V.34". www.itwissen.info.

Further reading

  • Coopersmith, Jonathan, Faxed: The Rise and Fall of the Fax Machine (Johns Hopkins University Press, 2015) 308 pp.

External links

The dictionary definition of facsimile at Wiktionary Media related to Fax machines at Wikimedia Commons

Apple Paladin

The Paladin is a conceptual combination of a computer, fax machine, scanner, and phone all-in-one designed by Apple Computer as a single office solution for a small business, as well as for use in hotel rooms for business travelers. It also went under the code name "Project X" during 1995.

It had a monochrome LCD screen and a phone handset attached to it (which fell off its hook too readily). Very few were prototyped and they are a rare find.

The system ran software called "Complete Office", which allowed the change between fax, phone, and PC all with the press of a button on the keypad. It also allowed for the user dial without needing to switch through multiple manual software protocols. By 1995 the engineers who had worked on the customized version of the OS were no longer working on the project making stability a major impediment.

Substantial conceptual work was done by the product design firm IDEO.

BoxRec

BoxRec or boxrec.com is a website dedicated to holding updated records of professional boxers, both male and female. It also maintains a MediaWiki-based encyclopaedia of boxing.

The objective of the site is to document every professional boxer and boxing match from the instigation of the Queensberry Rules up to the present times. BoxRec publishes ratings for all active boxers and all time ratings. Since 2012 the site has hosted Barry Hugman's History of World Championship Boxing.

European Economic Area

The European Economic Area (EEA), which was established via the EEA Agreement in 1992, is an international agreement which enables the extension of the European Union (EU)'s single market to non-EU member parties. The EEA links the European Union member states and three European Free Trade Association states (Iceland, Liechtenstein, and Norway) into an internal market governed by the same basic rules. These rules aim to enable free movement of labour, goods, services, and capital within the European Single Market, including the freedom to choose residence in any country within this area. The EEA was established on 1 January 1994 upon entry into force of the EEA Agreement. The contracting parties are the European Union (EU), its member states, and three EFTA member states.However, the EEA Treaty is a commercial treaty and differs from the EU Treaties in certain key respects. The EFTA members do not participate in the Common Agricultural Policy or the Common Fisheries Policy. According to Article 1 its purpose is to "promote a continuous and balanced strengthening of trade and economic relation." Unlike the EU Treaties, there is no mention of "ever closer union".

The right to free movement of persons between EEA member states and the relevant provisions on safeguard measures are identical to those applying between members of the European Union. The right and rules applicable in all EEA member states, including those which are not members of the EU, are specified in Directive 2004/38/EC and in the Agreement on the European Economic Area. The EEA Agreement specifies that membership is open to member states of either the European Union or European Free Trade Association (EFTA). EFTA states which are party to the EEA Agreement participate in the EU's internal market without being members of the EU or the European Union Customs Union. They adopt most EU legislation concerning the single market, with notable exclusions including laws regarding the Common Agricultural Policy and Common Fisheries Policy. The EEA's "decision-shaping" processes enable EEA EFTA member states to influence and contribute to new EEA policy and legislation from an early stage. Third country goods are excluded for these states on rules of origin.

When entering into force in 1994, the EEA parties were 17 states and two European Communities: the European Community, which was later absorbed into the EU's wider framework, and the now defunct European Coal and Steel Community. Membership has grown to 31 states as of 2016: 28 EU member states, as well as three of the four member states of the EFTA (Iceland, Liechtenstein and Norway). The Agreement is applied provisionally with respect to Croatia—the remaining and most recent EU member state—pending ratification of its accession by all EEA parties. One EFTA member, Switzerland, has not joined the EEA, but has a series of bilateral agreements with the EU which allow it also to participate in the internal market.

Fala language

Fala ("Speech", also called Xalimego) is a Romance language commonly classified in the Portuguese-Galician subgroup, with some traits from Leonese, spoken in Spain by about 10,500 people, of whom 5,500 live in a valley of the northwestern part of Extremadura near the border with Portugal. The speakers of Fala live in the towns of Valverde del Fresno (Valverdi du Fresnu), Eljas (As Ellas) and San Martín de Trevejo (Sa Martín de Trebellu).

Other names sometimes used for the language are Fala de Jálama or Fala de Xálima, but neither of them is used by the speakers themselves, who call their linguistic varieties lagarteiru (in Eljas), manhegu / mañegu (in San Martín de Trevejo) and valverdeiru (in Valverde del Fresno).

Even though it has no official status, and has little presence in schools and church, use of the language is vigorous, and the literacy rate in Fala is nearly 100%. As a linguistic community, speakers have a strong, independent identity; they have rejected implementing a standard orthography similar to or based on the Galician one. A translation of the New Testament has been published in Fala (2015).

Fax modem

A fax modem enables a computer to transmit and receive documents as faxes on a telephone line. A fax modem is like a data modem but is designed to transmit and receive documents to and from a fax machine or another fax modem. Some, but not all, fax modems do double duty as data modems. As with other modems, fax modems can be internal or external. Internal fax modems are often called fax boards.

In the early 1990s small business PCs commonly had a PC-based fax/modem card and fax software (typically WinFax Pro). Largely replaced by email, PC-based faxing with a fax/modem declined at the turn of the century. Where faxing from a PC is required there are a number of Internet-based faxing alternatives. Where businesses still had one or more traditional fax machines churning out pages, they were usually outnumbered by PCs processing E-mail.

Group 4 compression

CCITT Group 4 compression, also referred to as G4 or Modified Modified READ (MMR), is a lossless method of image compression used in Group 4 fax machines defined in the ITU-T T.6 fax standard. It is only used for bitonal (black and white) images. Group 4 compression is based on the Group 3 two-dimensional compression scheme (G3-2D), also known as Modified READ, which is in turn based on the Group 3 one-dimensional compression scheme (G3), also known as Modified Huffman coding. Group 4 compression is available in many proprietary image file formats as well as standardized formats such as TIFF, CALS, CIT (Intergraph Raster Type 24) and the PDF document format.

G4 offers a small improvement over G3-2D by removing the end of line (EOL) codes. G3 and G4 compression both treat an image as a series of horizontal black strips on a white page. Better compression is achieved when there are fewer unique black dots/lines on the page. Both G3-2D and G4 add a two dimensional feature to achieve greater compression by taking advantage of vertical symmetry. A worst-case image would be an alternating pattern of single-pixel black and white dots offset by one pixel on even/odd lines. G4 compression would actually increase the file size on this type of image. G4 typically achieves a 20:1 compression ratio. For an 8.5"×11" page scanned at 200 DPI, this equates to a reduction from 467.5 kB to 23.4 kB (95% compression ratio).

Internet fax

Internet fax, e-fax, or online fax is the use of the internet and internet protocols to send a fax (facsimile), rather than using a standard telephone connection and a fax machine. A distinguishing feature of Internet fax, compared to other Internet communications such as email, is the ability to exchange fax messages with traditional telephone-based fax machines.

JBIG

JBIG is an early lossless image compression standard from the Joint Bi-level Image Experts Group, standardized as ISO/IEC standard 11544 and as ITU-T recommendation T.82 in March 1993. It is widely implemented in fax machines. Now that the newer bi-level image compression standard JBIG2 has been released, JBIG is also known as JBIG1. JBIG was designed for compression of binary images, particularly for faxes, but can also be used on other images. In most situations JBIG offers between a 20% and 50% increase in compression efficiency over the Fax Group 4 standard, and in some situations, it offers a 30-fold improvement.

JBIG is based on a form of arithmetic coding developed by IBM (known as the Q-coder) that also uses a relatively minor refinement developed by Mitsubishi, resulting in what became known as the QM-coder. It bases the probability estimates for each encoded bit on the values of the previous bits and the values in previous lines of the picture. JBIG also supports progressive transmission, which generally incurs a small overhead in bit rate (around 5%).

Junk fax

Junk faxes are a form of telemarketing where unsolicited advertisements are sent via fax transmission. Junk faxes are the faxed equivalent of spam or junk mail. Proponents of this advertising medium often use the terms broadcast fax or fax advertising to avoid the negative connotation of the term junk fax. Junk faxes are generally considered to be a nuisance since they waste toner, ink and paper in fax machines.

List of embassies in Jakarta

This is a list of the embassies, high commissions and Apostolic Nunciature in Jakarta, Indonesia.As the capital city of Indonesia, Jakarta hosts a number of embassies of foreign countries that have established diplomatic relations with Indonesia. Currently, the capital city of Jakarta hosts 99 embassies. Several other countries accredit non-resident ambassadors from other capitals. In Jakarta, a large concentration of foreign embassies is clustered in the Menteng area and M.H. Thamrin Avenue in Central Jakarta, and also Jalan Jenderal Sudirman, Kuningan and Mega Kuningan area in South Jakarta.

Jakarta also serves as the seat of the Association of Southeast Asian Nations (ASEAN) Secretariat; a number of foreign countries have appointed their embassies to also serve as their representative and mission for ASEAN, thus making Jakarta as the diplomatic capital of ASEAN.

Mediafax

Mediafax (Romanian pronunciation: [ˌmedi.aˈfaks]) is a Romanian media company headquartered in Bucharest and founded in 1991. It is a part of the MediaPro Group and its primary line of business is a news and photography service. The company's Mediafax Business Information products include a variety of business news and data, such as currency market, business opportunities, calls for tender, statistics and company data.

Outland 2

Outland 2 is a collaborative album by Bill Laswell and Pete Namlook, released on April 9, 1996 by FAX +49-69/450464.

Taisei Corporation

Taisei Corporation (大成建設株式会社, Taisei Kensetsu Kabushiki-gaisha) (TYO: 1801) is a Japanese corporation founded in 1873. Its main areas of business are building construction, civil engineering, and real estate development. Taisei's headquarters are located at Shinjuku Center Building in Nishi-Shinjuku, Shinjuku, Tokyo.Taisei has 15 branch offices, 1 technology center, 46 domestic offices, 12 overseas offices, 29 consolidated subsidiaries and 43 affiliated companies accounted for by the equity-method.

Terminal (telecommunication)

In the context of telecommunications, a terminal is a device which ends a telecommunications link and is the point at which a signal enters and/or leaves a network. Examples of equipment containing network terminations are telephones, fax machines, computer terminals and network devices, printers and workstations.

Timeline of Apple Inc. products

This timeline of Apple Inc. products is a list of all stand-alone Apple II, Macintosh, and other computers, as well as computer peripherals, expansion cards, ancillary products, and consumer electronics sold by Apple Inc. This list is ordered by the release date of the products.

Wikispecies

Wikispecies is a wiki-based online project supported by the Wikimedia Foundation. Its aim is to create a comprehensive free content catalogue of all species; the project is directed at scientists, rather than at the general public. Jimmy Wales stated that editors are not required to fax in their degrees, but that submissions will have to pass muster with a technical audience. Wikispecies is available under the GNU Free Documentation License and CC BY-SA 3.0.

Started in September 2004, with biologists across the world invited to contribute, the project had grown a framework encompassing the Linnaean taxonomy with links to Wikipedia articles on individual species by April 2005.

Windows Fax and Scan

Windows Fax and Scan is an integrated faxing and scanning application included in some versions of the Windows Vista operating system and all versions of Windows 7, Windows 8 and Windows 10. Windows XP includes Fax Console instead. The software is not compatible with T.38 technology and cannot be used for internet faxes.

Windows Messaging

Windows Messaging, initially called Microsoft Exchange Client, is an email client that was included with Windows 95 (beginning with OSR2), 98 and Windows NT 4.0.

In Windows 98, it was not installed by default, but was available as a separate program in the setup CD. It is incompatible with Windows 2000, Windows ME, Windows XP and later versions.

Windows Photo Viewer

Windows Photo Viewer (formerly Windows Picture and Fax Viewer) is an image viewer included with the Windows NT family of operating systems. It was first included with Windows XP and Windows Server 2003 under its former name. It was temporarily replaced with Windows Photo Gallery in Windows Vista, but has been reinstated in Windows 7. This program succeeds Imaging for Windows. In Windows 10, it is deprecated in favor of a Universal Windows Platform app called Photos, although it can be brought back with a registry tweak.Windows Photo Viewer can show individual pictures, display all pictures in a folder as a slide show, reorient them in 90° increments, print them either directly or via an online print service, send them in e-mail or burn them to a disc. Windows Photo Viewer supports images in BMP, JPEG, JPEG XR (formerly HD Photo), PNG, ICO, GIF and TIFF file formats.

Official
Unofficial
History
Pioneers
Transmission
media
Network topology
and switching
Multiplexing
Networks

This page is based on a Wikipedia article written by authors (here).
Text is available under the CC BY-SA 3.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.