History of videotelephony

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A Tandberg T3 high definition telepresence room in use some 40 years after the introduction of Videophone#AT.26T Picturephone: 2019 black and white Picturephone (2008) Tandberg Image Gallery - telepresence-t3-side-view-hires.jpg
A Tandberg T3 high definition telepresence room in use some 40 years after the introduction of Videophone#AT.26T Picturephone: 2019 black and white Picturephone (2008)

The history of videotelephony covers the historical development of several technologies which enable the use of live video in addition to voice telecommunications. The concept of videotelephony was first popularized in the late 1870s in both the United States and Europe, although the basic sciences to permit its very earliest trials would take nearly a half century to be discovered. This was first embodied in the device which came to be known as the video telephone, or videophone, and it evolved from intensive research and experimentation in several telecommunication fields, notably electrical telegraphy, telephony, radio, and television.

Video electronic medium for the recording, copying and broadcasting of moving visual images

Video is an electronic medium for the recording, copying, playback, broadcasting, and display of moving visual media. Video was first developed for mechanical television systems, which were quickly replaced by cathode ray tube (CRT) systems which were later replaced by flat panel displays of several types.

Telecommunication Transmission of information between locations using electromagnetics

Telecommunication is the transmission of signs, signals, messages, words, writings, images and sounds or information of any nature by wire, radio, optical or other electromagnetic systems. Telecommunication occurs when the exchange of information between communication participants includes the use of technology. It is transmitted through a transmission media, such as over physical media, for example, over electrical cable, or via electromagnetic radiation through space such as radio or light. Such transmission paths are often divided into communication channels which afford the advantages of multiplexing. Since the Latin term communicatio is considered the social process of information exchange, the term telecommunications is often used in its plural form because it involves many different technologies.

Telephony is the field of technology involving the development, application, and deployment of telecommunication services for the purpose of electronic transmission of voice, fax, or data, between distant parties. The history of telephony is intimately linked to the invention and development of the telephone.

Contents

The development of the crucial video technology first started in the latter half of the 1920s in the United Kingdom and the United States, spurred notably by John Logie Baird and AT&T's Bell Labs. This occurred in part, at least with AT&T, to serve as an adjunct supplementing the use of the telephone. A number of organizations believed that videotelephony would be superior to plain voice communications. However video technology was to be deployed in analog television broadcasting long before it could become practical—or popular—for videophones.

John Logie Baird Scottish scientist, engineer, innovator and inventor of the worlds first television

John Logie BairdFRSE was a Scottish engineer, innovator, one of the inventors of the mechanical television, demonstrating the first working television system on 26 January 1926, and inventor of both the first publicly demonstrated colour television system, and the first purely electronic colour television picture tube.

Bell Labs Research and scientific development company

Nokia Bell Labs is an industrial research and scientific development company owned by Finnish company Nokia. With headquarters located in Murray Hill, New Jersey, the company operates several laboratories in the United States and around the world. Bell Labs has its origins in the complex past of the Bell System.

Analog television original television technology that uses analog signals to transmit video and audio; in an analog television broadcast, the brightness, colors and sound are represented by rapid variations of either the amplitude, frequency or phase of the signal

Analog television or analogue television is the original television technology that uses analog signals to transmit video and audio. In an analog television broadcast, the brightness, colors and sound are represented by rapid variations of either the amplitude, frequency or phase of the signal.

Videotelephony developed in parallel with conventional voice telephone systems from the mid-to-late 20th century. Very expensive videoconferencing systems rapidly evolved throughout the 1980s and 1990s from proprietary equipment, software and network requirements to standards-based technologies that were readily available to the general public at a reasonable cost. Only in the late 20th century with the advent of powerful video codecs combined with high-speed Internet broadband and ISDN service did videotelephony become a practical technology for regular use.

The public switched telephone network (PSTN) is the aggregate of the world's circuit-switched telephone networks that are operated by national, regional, or local telephony operators, providing infrastructure and services for public telecommunication. The PSTN consists of telephone lines, fiber optic cables, microwave transmission links, cellular networks, communications satellites, and undersea telephone cables, all interconnected by switching centers, thus allowing most telephones to communicate with each other. Originally a network of fixed-line analog telephone systems, the PSTN is now almost entirely digital in its core network and includes mobile and other networks, as well as fixed telephones.

A video codec is an electronic circuit or software that compresses or decompresses digital video. It converts uncompressed video to a compressed format or vice versa. In the context of video compression, "codec" is a concatenation of "encoder" and "decoder"—a device that only compresses is typically called an encoder, and one that only decompresses is a decoder.

Internet access individual connection to the internet

Internet access is the ability of individuals and organizations to connect to the Internet using computer terminals, computers, and other devices; and to access services such as email and the World Wide Web. Internet access is sold by Internet service providers (ISPs) delivering connectivity at a wide range of data transfer rates via various networking technologies. Many organizations, including a growing number of municipal entities, also provide cost-free wireless access.

With the rapid improvements and popularity of the Internet, videotelephony has become widespread through the deployment of video-enabled mobile phones, plus videoconferencing and computer webcams which utilize Internet telephony. In the upper echelons of government, business and commerce, telepresence technology, an advanced form of videoconferencing, has helped reduce the need to travel.

Mobile phone Portable device to make telephone calls using a radio link

A mobile phone, cell phone, cellphone, or hand phone, sometimes shortened to simply mobile, cell or just phone, is a portable telephone that can make and receive calls over a radio frequency link while the user is moving within a telephone service area. The radio frequency link establishes a connection to the switching systems of a mobile phone operator, which provides access to the public switched telephone network (PSTN). Modern mobile telephone services use a cellular network architecture, and, therefore, mobile telephones are called cellular telephones or cell phones, in North America. In addition to telephony, 2000s-era mobile phones support a variety of other services, such as text messaging, MMS, email, Internet access, short-range wireless communications, business applications, video games, and digital photography. Mobile phones offering only those capabilities are known as feature phones; mobile phones which offer greatly advanced computing capabilities are referred to as smartphones.

Webcam computer-connected video camera that streams its image in real time to a computer network

A webcam is a video camera that feeds or streams an image or video in real time to or through a computer to a computer network, such as the Internet. Webcams are typically small cameras that sit on a desk, attach to a user's monitor, or are built into the hardware. Webcams can be used during a video chat session involving two or more people, with conversations that include live audio and video. For example, Apple's iSight camera, which is built into Apple laptops, iMacs and a number of iPhones, can be used for video chat sessions, using the iChat instant messaging program. Webcam software enables users to record a video or stream the video on the Internet. As video streaming over the Internet requires a lot of bandwidth, such streams usually use compressed formats. The maximum resolution of a webcam is also lower than most handheld video cameras, as higher resolutions would be reduced during transmission. The lower resolution enables webcams to be relatively inexpensive compared to most video cameras, but the effect is adequate for video chat sessions.

Voice over Internet Protocol (VoIP), also called IP telephony, is a method and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. The terms Internet telephony, broadband telephony, and broadband phone service specifically refer to the provisioning of communications services over the public Internet, rather than via the public switched telephone network (PSTN), also known as plain old telephone service (POTS).

Early history

"Fiction becomes fact": Imaginary "Edison" combination videophone-television, conceptualized by George du Maurier and published in Punch. The drawing also depicts then-contemporary speaking tubes, used by the parents in the foreground and their daughter on the viewing display (1878). Telephonoscope.jpg
"Fiction becomes fact": Imaginary "Edison" combination videophone-television, conceptualized by George du Maurier and published in Punch. The drawing also depicts then-contemporary speaking tubes, used by the parents in the foreground and their daughter on the viewing display (1878).

Barely two years after the telephone was first patented in the United States in 1876 by Dr.[ citation needed ] Alexander Graham Bell, an early concept of a combined videophone and wide-screen television called a telephonoscope was conceptualized in the popular periodicals of the day. It was also mentioned in various early science fiction works such as Le Vingtième siècle. La vie électrique (The 20th century. The electrical life) and other works written by Albert Robida, and was also sketched in various cartoons by George du Maurier as a fictional invention of Thomas Edison. One such sketch was published on December 9, 1878 in Punch magazine. [1] [2] [3]

Alexander Graham Bell scientist and inventor known for his work on the telephone

Alexander Graham Bell was a Scottish-born American inventor, scientist, and engineer who is credited with inventing and patenting the first practical telephone. He also co-founded the American Telephone and Telegraph Company (AT&T) in 1885.

Telephonoscope 19th century early concept of videophone and television

A telephonoscope was an early concept of videophone and television, conceptualized in the late 1870s through the 1890s. It was mentioned in various early science fiction works such as Le Vingtième siècle. La vie électrique and other works written by Albert Robida. It was also sketched in various cartoons by George du Maurier as a fictional invention by Thomas Edison including one made on December 9, 1878 in Punch magazine.

The term 'telectroscope' was also used in 1878 by French writer and publisher Louis Figuier, to popularize an invention wrongly interpreted as real and incorrectly ascribed to Dr. Bell, possibly after his Volta Laboratory discreetly deposited a sealed container of a Graphophone phonograph at the Smithsonian Institution for safekeeping. [4] [5] Written under the pseudonym "Electrician", one article earlier claimed that "an eminent scientist" had invented a device whereby objects or people anywhere in the world "....could be seen anywhere by anybody". The device, among other functions, would allow merchants to transmit pictures of their wares to their customers, and the contents of museum collections to be made available to scholars in distant cities...." [6] [Note 1] In the era prior to the advent of broadcasting, electrical "seeing" devices were conceived as adjuncts to the telephone, thus creating the concept of a videophone. [7] [8]

Telectroscope

The telectroscope was the first conceptual model of a television or videophone system. The term was used in the 19th century to describe science-based systems of distant seeing.

Louis Figuier French scientist and writer

Louis Figuier was a French scientist and writer. He was the nephew of Pierre-Oscar Figuier and became Professor of chemistry at L'Ecole de pharmacie of Montpellier. Though his works are highly respected, it is often unmentioned that he was in fact a staunch racist of the time. Figuier played a key role in perpetuating the blatantly myopic misconception that people of black origin were mentally inferior, were not fully human, smelled poorly, and were promiscuous. His citing of these ill-formed concepts of course were and are not true yet he remains celebrated in his achievements.

Graphophone phonograph

The Graphophone was the name and trademark of an improved version of the phonograph. It was invented at the Volta Laboratory established by Alexander Graham Bell in Washington, D.C., United States.

Fraudulent reports of 'amazing' advances in video telephones would be publicized as early as 1880 and would reoccur every few years, such as the episode of 'Dr. Sylvestre' of Paris who claimed in 1902 to have invented a powerful (and inexpensive) video telephone, termed a 'spectograph', the intellectual property rights he believed were worth $5,000,000. After reviewing his claim Dr. Bell denounced the supposed invention as a "fairy tale", and publicly commented on the charlatans promoting bogus inventions for financial gain or self-promotion. [9] [10]

However Dr. Alexander Graham Bell personally thought that videotelephony was achievable even though his contributions to its advancement were incidental. [11] In April 1891, Dr. Bell actually did record conceptual notes on an 'electrical radiophone', which discussed the possibility of "seeing by electricity" using devices that employed tellurium or selenium imaging components. [12] Bell wrote, decades prior to the invention of the image dissector: [12] [13]

Should it be found ... [that the image sensor] is illuminated, then an apparatus might be constructed in which each piece of selenium is a mere speck, like the head of a small pin, the smaller the better. The darkened selenium should be placed in a cup-like receiver which can fit over the eye ... Then, when the first selenium speck is presented to an illuminated object, it may be possible that the eye in the darkened receiver, should perceive, not merely light, but an image of the object ...

Bell went on to later predict that: "...the day would come when the man at the telephone would be able to see the distant person to whom he was speaking." [14] [15] The discoveries in physics, chemistry and materials science underlying video technology would not be in place until the mid-1920s, first being utilized in electromechanical television. More practical 'all-electronic' video and television would not emerge until 1939, but would then suffer several more years of delays before gaining popularity due to the onset and effects of World War II.

Artist's conception: 21st-century videotelephony imagined in the early 20th century (1910) France in XXI Century. Correspondance cinema.jpg
Artist's conception: 21st-century videotelephony imagined in the early 20th century (1910)

The compound name 'videophone' slowly entered into general usage after 1950, [16] although 'video telephone' likely entered the lexicon earlier after video was coined in 1935. [17] Prior to that time there appeared to be no standard terms for 'video telephone', with expressions such as 'sight-sound television system', 'visual radio' and nearly 20 others (in English) being used to describe the marriage of telegraph, telephone, television and radio technologies employed in early experiments. [18] [19] [20]

Among the technological precursors to the videophone were telegraphic image transmitters created by several companies, such as the wirephoto used by Western Union, and the teleostereograph developed by AT&T's Bell Labs, [21] which were forerunners of today's fax (facsimile) machines. Such early image transmitters were themselves based on previous work by Ernest Hummel and others in the 19th century. By 1927 AT&T had created its earliest electromechanical television-videophone called the ikonophone (from Greek: 'image-sound'), [22] which operated at 18 frames per second and occupied half a room full of equipment cabinets. [23] [24] An early U.S. test in 1927 had their then-Commerce Secretary Herbert Hoover address an audience in New York City from Washington, D.C.; although the audio portion was two-way, the video portion was one-way with only those in New York being able to see Hoover.

Bell Labs videophone prototype (1927), front view, MoMI.jpg
Bell Labs videophone prototype (1927), side view, MoMI.jpg
A 1927 Bell Labs videophone prototype (its Nipkow disk not visible), exhibited at the Museum of the Moving Image in New York

By 1930, AT&T's 'two-way television-telephone' system was in full-scale experimental use. [7] [20] The Bell Labs' Manhattan facility devoted years of research to it during the 1930s, led by Dr. Herbert Ives along with his team of more than 200 scientists, engineers and technicians, intending to develop it for both telecommunication and broadcast entertainment purposes. [8] [25]

There were also other public demonstrations of "two-way television-telephone" systems during this period by inventors and entrepreneurs who sought to compete with AT&T, although none appeared capable of dealing with the technical issues of signal compression that Bell Labs would eventually resolve. Signal compression, and its later sibling data compression were fundamental to the issue of transmitting the very large bandwidth of low-resolution black and white video through the very limited capacity of low-speed copper PSTN telephone lines (higher resolution colour videophones would require even far greater capabilities). [Note 2] After the Second World War, Bell Labs resumed its efforts during the 1950s and 1960s, eventually leading to AT&T's Picturephone.

World's first public videophone service: Germany 1936–1940

In early 1936 the world's first public video telephone service, Germany's Gegensehn-Fernsprechanlagen (visual telephone system), was developed by Dr. Georg Schubert, who headed the development department at the Fernseh-AG, a technical combine for television broadcasting technology. [27] It was opened by the German Reichspost (post office) between Berlin and Leipzig, utilizing broadband coaxial cable to cover the distance of approximately 160 km (100 miles).

Schubert's system was based on Gunter Krawinkel's earlier research of the late-1920s that he displayed at the 1929 Internationale Funkausstellung Berlin (Berlin International Radio Exposition). [28] Schubet's higher performance system employed mechanical television scanning and 20 cm (8 inch) square displays with a resolution of 180 lines (initially 150 lines), [28] [29] [30] transmitting some 40,000 pixels per frame at 25 frames per second. [31]

After the transistor was invented at Bell Labs in 1948, an AT&T electrical engineer predicted:

Harold Osborne, 1948 [32]

The system's opening was inaugurated by the Minister of Posts Paul von Eltz-Rübenach in Berlin on March 1, 1936, who viewed and spoke with Leipzig's chief burgomaster. [33] [34] It employed a Nipkow disk flying-spot scanner for its transmitter, and a cathode ray display tube with (an initial) resolution of 150 lines at its receiving-end videophone booth. [28] The same coaxial cables were also used to distribute television programming.

In the initial service trial, broadband coaxial cable lines initially linked Berlin to Leipzig. After a period of experimentation the system entered public use and was soon extended another 160 km (100 miles) from Berlin to Hamburg, and then in July 1938 from Leipzig to Nuremberg and Munich. The system eventually operated with more than 1,000 km (620 miles) of coaxial cable transmission lines. The videophones were integrated within large public videophone booths, with two booths provided per city. Calls between Berlin and Leipzig cost RM3½, approximately one sixth of a British pound sterling, or about one-fifteenth of the average weekly wage. [29] The video telephone equipment used in Berlin was designed and built by the German Post Office Laboratory. Videophone equipment used in other German cities were developed by Fernseh A.G., partly owned by Baird Television Ltd. of the U.K., [29] inventors of the world's first functional television. During its life the German system underwent further development and testing, resulting in higher resolutions and a conversion to an all-electronic camera tube transmission system to replace its mechanical Nipkow scanning disc. [28] While the system's image quality was primitive by modern standards, it was deemed impressive in contemporary reports of the era, with users able to clearly discern the hands on wristwatches. [29]

The special public videophone service was offered to the general public, which had to visit special post office Fernsehsprechstellen (video telephone booths, from "far sight speech place") simultaneously in their respective cities, [31] but which at the same time also had Nazi political and propagandistic overtones similar to the broadcasting of the 1936 Olympic Games in Berlin. [35] The German post office announced ambitious plans to extend their public videophone network to Cologne, Frankfurt and Vienna, Austria, but expansion plans were discontinued in 1939 with the start of the Second World War. [36] [37] After Germany subsequently became fully engaged in the war its public videophone system was closed in 1940, with its expensive inter-city broadband cables converted to telegraphic message traffic and broadcast television service. [28] [38]

A similar commercial post office system was also created in France during the late-1930s. [39] The Deutsche Bundespost postal service would decades later develop and deploy its BIGFON (Broadband Integrated Glass-Fiber Optical Network) videotelephony network from 1981 to 1988, serving several large German cities, and also created one of Europe's first public switched broadband services in 1989. [40]

AT&T Picturephone: 1964

In the United States AT&T's Bell Labs conducted extensive research and development of videophones, eventually leading to public demonstrations of its trademarked Picturephone product and service in the 1960s. Its large Manhattan experimental laboratory devoted years of technical research during the 1930s, led by Dr. Herbert Ives along with his team of more than 200 scientists, engineers and technicians. [8] [25] The Bell Labs early experimental model of 1930 had transmitted uncompressed video through multiple phone lines, a highly impractical and expensive method unsuitable for commercial use. [41]

During the mid-1950s, its laboratory work had produced another early test prototype capable of transmitting still images every two seconds over regular analog PSTN telephone lines. [30] [39] The images were captured by the Picturephone's compact Vidicon camera and then transferred to a storage tube or magnetic drum for transmission over regular phone lines at two-second intervals to the receiving unit, which displayed them on a small cathode-ray television tube. [28] AT&T had earlier promoted its experimental video for telephone service at the 1939 New York World's Fair. [42]

The more advanced Picturephone Mod I's early promotion included public evaluation displays at Disneyland and the 1964 New York World's Fair, with the first transcontinental videocall between the two venues made on April 20, 1964. [43] [44] The first Picturephone 'Mod I' (Model No. 1) demonstration units used small oval housings on swivel stands, intended to stand on desks. Similar AT&T Picturephone units were also featured at the Telephone Pavilion (also called the "Bell Telephone Pavilion") at Expo 67, an International World's Fair held in Montreal, Canada in 1967. [44] [45] [46] Demonstration units were available at the fairs for the public to test, with fairgoers permitted to make videophone calls to volunteer recipients at other locations.

The United States would not see its first public videophone booths until 1964, when AT&T installed their earliest commercial videophone units, the Picturephone "Mod I", in booths that were set up in New York's Grand Central Terminal, Washington D.C., and Chicago. [23] Its system was the result of decades of research and development at Bell Labs, its principal supplier, Western Electric, plus other researchers working under contract to the Bell Labs. [41] However the use of reservation time slots and their cost of US$16 (Washington, D.C. to New York) to $27 (New York to Chicago) (equivalent to $118 to $200 in 2012 dollars) for a three-minute call at the public videophone booths greatly limited their appeal resulting in their closure by 1968. [14] [23]

Picturephones were also later installed in the offices of Westinghouse and Alcoa in Pittsburgh, as well as other technology companies in that city. [41] AT&T's commercial service in Pittsburgh started on June 30, 1970 with 38 Picturephones at eight companies, at a lease rate of $160 per month ($947/month in 2012 dollars) for the service, which provided for 30 minutes of videocalling time per month, with extra minutes costing 25 cents each. [Note 3]

Color on AT&T's Picturephone was not employed with their early models. These Picturephone units packaged Plumbicon cameras and small CRT displays within their housings. The cameras were located atop their screens to help users see eye to eye. Later generation display screens were larger than in the original demonstration units, approximately six inches (15 cm) square in a roughly cubical cabinet.

Picturephone technology

An experimental Philips videophone demonstration, Netherlands (1974 video, 1:23) (in Dutch)

The Picturephone's video bandwidth was 1 MHz with a vertical scan rate of 30 Hz, horizontal scan rate of 8 kHz, and about 250 visible scan lines.[ citation needed ] The equipment included a speakerphone (hands free telephone), with an added box to control picture transmission. Each Picturephone line used three twisted pairs of ordinary telephone cable, two pairs for video and one for audio and signaling. [47] Cable amplifiers were spaced about a mile apart (1.6 kilometres) with built-in six-band adjustable equalization filters. For distances of more than a few miles, the signal was digitized at 2 MHz and 3 bits per sample DPCM, and transmitted on a T-2 carrier. [44]

The original Picturephone system used contemporary crossbar and multi-frequency operation. Lines and trunks were six wire, one pair each way for video and one pair two way for audio. MF address signaling on the audio pair was supplemented by a Video Supervisory Signal (VSS) looping around on the video quad to ensure continuity. More complex protocols were later adopted for conferencing. [44]

To deploy Picturephone service, new wideband crossbar switches were designed and installed into the Bell System's 5XB switch offices, this being the most widespread of the relatively modern kind. [44] Hundreds of technicians attended schools to learn to operate the Cable Equalizer Test Set and other equipment, and to install Picturephones.

Lack of Picturephone success

At the time of its first launch, AT&T foresaw a hundred thousand Picturephones in use across the Bell System by 1975. However, by the end of July 1974, only five Picturephones were being leased in Pittsburgh, and U.S.-wide there were only a few hundred, mostly in Chicago. [41] Unrelated difficulties at New York Telephone also slowed AT&T's efforts, and few customers signed up for the service in either city. At its peak Picturephone service had only about 500 subscribers, with the service fading away through the 1970s.

AT&T's initial Picturephone 'Mod I' (Model No. 1) and then its upgraded 'Mod II' programs, were a continuation of its many years of prior research during the 1920s, 1930s, late 1940s and 1950s. Both Picturephone programs, like their experimental AT&T predecessors, were researched principally at its Bell Labs, formally spanned some 15 years and consumed more than US$500 million, [Note 4] eventually meeting with commercial failure. [48] AT&T concluded that its early Picturephone was a "concept looking for a market" [48] and discontinued its 'Mod II' service in the late 1970s. [48]

Later development

AT&T would later market its VideoPhone 2500 to the general public from 1992 to 1995 [49] with prices starting at US$1,500 (approximately $2,680 in current dollars) [50] and later dropping to $1,000 ($1,730 in current dollars), marketed by its Global VideoPhone Systems unit. [51] The VideoPhone 2500 was designed to provide low-frame rate compressed color video on ordinary Plain Old Telephone Service (POTS) lines, circumventing the significantly higher cost ADSL telephone service lines used by several other videoconferencing manufacturers. It was limited by analog phone line connection speeds of about 19 Kilobits per second, the video portion being 11,200 bit/s, and with a maximum frame rate of 10 frames per second, but typically much slower, as low as a third of a video frame per second. The VideoPhone 2500 used proprietary technology protocols, including AT&T's Global VideoPhone Standard (GVS). [49] Again, AT&T met with very little commercial success, selling only about 30,000 units, mainly outside the United States. [49]

Despite AT&T's various videophone products meeting with commercial failure, they were widely viewed as technical successes which expanded the limits of the telecommunications sciences in several areas. Its videotelephony programs were critically acclaimed for their technical brilliance and even the novel uses they experimented with. The research and development programs conducted by Bell Labs were highly notable for their beyond-the-state-of-the-art results produced in materials science, advanced telecommunications, microelectronics and information technologies.

AT&T's published research additionally helped pave the way for other companies to later enter the field of videoconferencing. The company's videophones also generated significant media coverage in science journals, the general news media and in popular culture. The image of a futuristic AT&T videophone being casually used in the science fiction film 2001: A Space Odyssey, became iconic of both the movie and, arguably, the public's general view of the future.

Other early videophones: 1968–1984

Beginning in the late 1960s, several countries worldwide sought to compete with AT&T's advanced development of its Picturephone service in the United States. However such projects were research and capital intensive, and fraught with difficulties in being deployed commercially.

France

The French Matra videophone (1970) Videophone IMG 1107-white.jpg
The French Matra videophone (1970)

France's post office telecommunications branch had earlier set up a commercial videophone system similar to the German Reichspost public videophone system of the late 1930s. [39] In 1972 the defense and electronics manufacturer Matra was one of three French companies that sought to develop advanced videophones in the early 1970s, spurred by the AT&T's Picturephone in the United States. Initial plans by Matra included the deployment of 25 units to France's Centre national d'études des télécommunications (CNET of France Télécom) for their internal use. CNET intended to guide its initial use towards the business sector, to be later followed by personal home usage. Its estimated unit cost in 1971 was the equivalent of £325, with a monthly usage subscription charge of £3.35. [52]

Studies of applications of videotelephony were conducted by CNET in France in 1972, with its first commercial applications for videophones appearing in 1984. The delay was due to the problem of insufficient bandwidth, with 2 Mb per second being required for transmitting both video and audio signals. The problem was solved worldwide by the creation of software for data encoding and compression via video coding and decoding algorithms, also known as codecs.

Sweden

Swedish Prime Minister Tage Erlander using an Ericsson videophone to speak with Lennart Hyland, a popular TV show host (1969) Tage Erlander 1960-tal.jpg
Swedish Prime Minister Tage Erlander using an Ericsson videophone to speak with Lennart Hyland, a popular TV show host (1969)

In Sweden, electronics maker Ericsson began developing a videophone in the mid-1960s, intending to market it to government, institutions, businesses and industry, but not to consumers due to AT&T's lack of success in that market segment. Tests were conducted in Stockholm, including trial communications in banking. Ultimately Ericsson chose not to proceed with further production. [53]

United Kingdom

In 1970 the British General Post Office had 16 demonstration models of its Viewphone built, meant to be the equivalent to AT&T's Picturephone. [54] Their initial attempt at a first generation commercial videophone later led to the British Telecom Relate 2000, which was released for sale in 1993, costing between £400-£500 each. The Relate 2000 featured a 74 millimetres (2.9 in) flip-up colour LCD display screen operating at a nominal rate of 8 video frames per second, which could be depressed to 3-4 frames per second if the PSTN bandwidth was limited. In the era prior to low-cost, high-speed broadband service, its video quality was found to be generally poor by the public with images shifting jerkily between frames, due to British phone lines that generally provided less than 3.4 kHz of bandwidth. [30] British Telecom had initially expected the device, manufactured by Marconi Electronics, to sell at a rate of 10,000 per year, but its actual sales were minimal. [39] [55] [56] Its second generation videophone thus also proved to be commercially unsuccessful, [39] [57] similar to AT&T's VideoPhone 2500 of the same time period.

Digital videotelephony: 1985–1999

This time period saw the research, development and commercial roll-out of what would become powerful video compression and decompression software codecs, which would eventually lead to low cost videotelephony in the early 2000s.

Video compression

Practical digital videotelephony was only made possible with advances in video compression, due to the impractically high bandwidth requirements of uncompressed video. To achieve Video Graphics Array (VGA) quality video (480p resolution and 256 colors) with raw uncompressed video, it would require a bandwidth of over 92  Mbps. [58] The most important compression technique that enabled practical digital videotelephony and videoconferencing is the discrete cosine transform (DCT). [58] [59] The DCT, a form of lossy compression, was proposed in 1972 by Nasir Ahmed, who developed the algorithm with T. Natarajan and K. R. Rao at the University of Texas in 1973. [60] The DCT algorithm became the basis for the first practical video coding standard that was useful for videoconferencing, H.261, standardised by the ITU-T in 1988. [59]

Japanese videophones

In Japan the Lumaphone was developed and marketed by Mitsubishi in 1985. The project was originally started by the Ataritel division of the Atari Video Game Company in 1983 under the direction of Atari's Steve Bristow. [61] Atari then sold its division to Mitsubishi Electric in 1984. The Lumaphone was marketed by Mitsubishi Electric of America in 1986 as the Luma LU-1000, costing US$1,500, [62] designed with a small black and white video display, approximately 4 centimetres (1.6 in) in size, and a video camera adjacent to the display which could be blocked with a sliding door for privacy. Although promoted as a 'videophone', it operated similar to Bell Labs' early experimental image transfer phone of 1956, transmitting still images every 3–5 seconds over analog POTS lines. It could also be hooked up to a printer or connected to a regular TV or monitor for improved teleconferencing. [63] [64]

The Kyocera VP-210 Visual Phone was the first commercial mobile videophone. The Personal Handy-phone System (PHS) phone was introduced in Japan (1999). Kyocera VP-210 CP+ 2011.jpg
The Kyocera VP-210 Visual Phone was the first commercial mobile videophone. The Personal Handy-phone System (PHS) phone was introduced in Japan (1999).

Mitsubishi also marketed its lower-cost VisiTel LU-500 image phone in 1988 costing about US$400, aimed at the consumer market. It came with reduced capabilities but had with a larger black and white display. Other Japanese electronic manufacturers marketed similar image transfer phones during the late-1980s, including Sony's PCT-15 (US$500), and two models from Panasonic, its WG-R2 (US$450) and its KX-TV10 (US$500). [62] [65]

Much later the Kyocera Corporation, an electronics manufacturer based in Kyoto, conducted a two-year development campaign from 1997 to 1999 that resulted in the release of the VP-210 VisualPhone, the world's first mobile colour videophone that also doubled as a camera phone for still photos. [66] [67] The camera phone was the same size as similar contemporary mobile phones, but sported a large camera lens and a 5 cm (2 inch) colour TFT display capable of displaying 65,000 colors, and was able to process two video frames per second. The 155 gram (5.5 oz.) camera could also take 20 photos and convey them by e-mail, with the camera phone retailing at the time for 40,000 yen, about US$325 in 1999. [67] [68]

The VP-210 was released in May 1999 and used its single front-facing 110,000-pixel camera to send two images per second through Japan's PHS mobile phone network system. Although its frame rate was crude and its memory is considered tiny in the present day, the phone was viewed as "revolutionary" at the time of its release. [68]

The Kyocera project was initiated at their Yokohama research and development center by Kazumi Saburi, one of their section managers. His explanation for the project was "Around that time, cellular handsets with enabled voice and SMS communication capabilities were considered to be just one among many personal communication tools. One day a simple idea hit us - 'What if we were able to enjoy talking with the intended person watching his/her face on the display?' We were certain that such a device would make cell phone communications much more convenient and enjoyable." [69]

Saburi also stated that their R&D section had "nourished [the idea] for several years before" they received project approval from their top management which had encourage such forward-thinking research, because they "also believed that such a product would improve Kyocera's brand image." Their research showed that a "cell phone with a camera and color display provided a completely new value for users, It could be used as a phone, a camera and a photo album". [69]

Technical challenges handled by about a dozen engineers at Kyocera over the two year development period included the camera module's placement within the phone at a time when electronic components had not been fully reduced in size, as well as increasing its data transmission rate. After its release the mobile video-camera phone was commercially successful, spawning several other competitors such as the DDI Pocket, and one from Vodafone K.K. [69]

Videophone improvements: post-2000

Typical low-cost webcam used with many personal computers Webcam000c1.jpg
Typical low-cost webcam used with many personal computers

Significant improvements in video call quality of service for the deaf occurred in the United States in 2003 when Sorenson Media Inc. (formerly Sorenson Vision), a video compression software coding company, developed its VP-100 model stand-alone videophone specifically for the deaf community. It was designed to output its video to the user's television in order to lower the cost of acquisition, and to offer remote control and a powerful video compression codec for unequaled video quality and ease of use with a video relay service (VRS). Favourable reviews quickly led to its popular usage at educational facilities for the deaf, and from there to the greater deaf community. [70]

Coupled with similar high-quality videophones introduced by other electronics manufacturers, the availability of high speed Internet, and sponsored video relay services authorized by the U.S. Federal Communications Commission in 2002, VRS services for the deaf underwent rapid growth in that country. [70]

See also

Notes

  1. Although the pseudonymous letter was accompanied by a technical description of how the telectroscope would work and was published in a reputable New York newspaper, researchers later noted that it was published close to April Fools' Day and believed the article was submitted as an elaborate hoax. [6]
  2. One such demonstration that likely omitted any signal compression was performed in Mobile, Alabama on April 27, 1938. An Alabama news article reported that a "...technician of the American Television Institute, [promoted a videophone from a display booth for] the Roche Home Equipment Company... and through the medium of a scientific marvel... flashed a living picture over an ordinary telephone wire. Forming a practical insight into things that are to come, the television contrivance afforded a small, but clear, picture of speakers at each end of the wire." [26]
  3. Several uses of the Picturephone were novel and ahead of their time. At Alcoa in Pittsburgh, their Picturephone system was integrated into the company's corporate Information Technology system under its APRIS, or Alcoa Picturephone Remote Information System. APRIS let users retrieve information from Alcoa's databases, controlled by the buttons on their touch-tone telephones, with the data being presented on their Picturephone's video display, long before computer monitors came into popular use. [41] AT&T's Bell Labs would also soon experiment with multiple users on the same videocall, creating one of the earliest forms of videoconferencing.
  4. The $500M figure is attributed only to the AT&T and Bell Labs' 15 year program covering its Picturephone Mod I and Mod II versions. Earlier videotelephony programs during the later half of the 1920s, 1930s, late 1940s and 1950s, plus the AT&T VideoPhone 2500 model program of the late 1980s led to a cumulative cost which approached, by some estimates, one billion dollars in total for all videotelephony development.

Related Research Articles

Digital video is an electronic representation of moving visual images (video) in the form of encoded digital data. This is in contrast to analog video, which represents moving visual images with analog signals. Digital video comprises a series of digital images displayed in rapid succession.

Digital camera Camera that captures photographs or video in digital format

A digital camera or digicam is a camera that captures photographs in digital memory. Most cameras produced today are digital, and while there are still dedicated digital cameras, many more cameras are now being incorporated into mobile devices, portable touchscreen computers, which can, among many other purposes, use their cameras to initiate live video-telephony and directly edit and upload imagery to others. However, high-end, high-definition dedicated cameras are still commonly used by professionals.

A digital image is a numeric representation, normally binary, of a two-dimensional image. Depending on whether the image resolution is fixed, it may be of vector or raster type. By itself, the term "digital image" usually refers to raster images or bitmapped images.

Camera phone mobile phone which is able to capture still photographs

A camera phone is a mobile phone which is able to capture photographs and often record video using one or more built-in digital cameras. It can also send the resulting image over the telephone function. The first commercial camera phone was the Kyocera Visual Phone VP-210, released in Japan in May 1999.It was a cordless phone as distinct from a cellular mobile phone.

Videotelephony reception and transmission of audio-video signals by users at different locations

Videotelephony comprises the technologies for the reception and transmission of audio-video signals by users at different locations, for communication between people in real-time. A videophone is a telephone with a video display, capable of simultaneous video and audio for communication between people in real-time. Videoconferencing implies the use of this technology for a group or organizational meeting rather than for individuals, in a videoconference. Telepresence may refer either to a high-quality videotelephony system or to meetup technology, which goes beyond video into robotics. Videoconferencing has also been called "visual collaboration" and is a type of groupware.


H.320 or Narrow-band visual telephone systems and terminal equipment is an umbrella Recommendation by the ITU-T for running Multimedia (Audio/Video/Data) over ISDN based networks. The main protocols in this suite are H.221, H.230, H.242, audio codecs such as G.711, and video codecs such as H.261 and H.263.

H.324 is an ITU-T recommendation for voice, video and data transmission over regular analog phone lines. It uses a regular 33,600 bit/s modem for transmission, the H.263 codec for video encoding and G.723.1 for audio.

History of the camera camera

The history of the camera begins even before the introduction of photography. Cameras evolved from the camera obscura through many generations of photographic technology — daguerreotypes, calotypes, dry plates, film — to the modern day with digital cameras and camera phones.

History of telecommunication aspect of history relating to telecommunications

The history of telecommunication began with the use of smoke signals and drums in Africa, the Americas and parts of Asia. In the 1790s, the first fixed semaphore systems emerged in Europe. However, it was not until the 1830s that electrical telecommunication systems started to appear. This article details the history of telecommunication and the individuals who helped make telecommunication systems what they are today. The history of telecommunication is an important part of the larger history of communication.

Video relay service

A video relay service (VRS), also sometimes known as a video interpreting service (VIS), is a video telecommunication service that allows deaf, hard-of-hearing, and speech-impaired (D-HOH-SI) individuals to communicate over video telephones and similar technologies with hearing people in real-time, via a sign language interpreter.

Telerehabilitation is the delivery of rehabilitation services over telecommunication networks and the internet. Most types of services fall into two categories: clinical assessment, and clinical therapy. Some fields of rehabilitation practice that have explored telerehabilitation are: neuropsychology, speech-language pathology, audiology, occupational therapy, and physical therapy. Telerehabilitation can deliver therapy to people who cannot travel to a clinic because the patient has a disability or because of travel time. Telerehabilitation also allows experts in rehabilitation to engage in a clinical consultation at a distance.

The following outline is provided as an overview of and topical guide to telecommunication:

Video remote interpreting

Video remote interpreting (VRI) is a videotelecommunication service that uses devices such as web cameras or videophones to provide sign language or spoken language interpreting services. This is done through a remote or offsite interpreter, in order to communicate with persons with whom there is a communication barrier. It is similar to a slightly different technology called video relay service, where the parties are each located in different places. VRI is a type of telecommunications relay service (TRS) that is not regulated by the FCC.

Herbert E. Ives American physicist

Herbert Eugene Ives was a scientist and engineer who headed the development of facsimile and television systems at AT&T in the first half of the twentieth century. He is best known for the 1938 Ives–Stilwell experiment, which provided direct confirmation of special relativity's time dilation, although Ives himself did not accept special relativity, and argued instead for an alternative interpretation of the experimental results.

Telephone Pavilion (Expo 67) film

The Telephone Pavilion, also known as the Bell Telephone Pavilion and formally named the Telephone Association of Canada Pavilion, was a part of Expo 67, an International World's Fair held in Montreal, Quebec, Canada in 1967 to mark the centenary of the Confederation of Canada. The pavilion was built to promote Canadian telephone companies and their services. The pavilion's feature attraction was Canada '67, a documentary film directed by Robert Barclay for The Walt Disney Company. The movie was presented in Circle-Vision 360° to audiences of 1,200–1,500 people every 30 minutes.

Front-facing camera feature of cameras, mobile phones, smartphones, tablets and similar mobile devices that allows taking a self-portrait photograph or video while looking at the display of the device, usually showing a live preview of the image

A front-facing camera is a common feature of cameras, mobile phones, smartphones, and tablets. While stand-alone cameras face forward, away from the operator, tablets, smartphones and similar mobile devices typically have a camera facing the operator to allow taking a self-portrait photograph or video while looking at the display of the device, usually showing a live preview of the image. These are called front-facing cameras and are important for videotelephony and the taking of selfies.

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Further reading