Videophone

A videophone is a telephone with a video screen, and is capable of full duplex (bi-directional) video and audio transmissions for communication between people in real-time. It was the first form of videotelephony, later to be followed by videoconferencing, webcams, and finally telepresence.

At the dawn of the technology, videotelephony also included image phones which would exchange still images between units every few seconds over conventional POTS-type telephone lines, essentially the same as slow scan TV systems.

Currently videophones are particularly useful to the deaf and speech-impaired who can use them with sign language, and also with video relay services to communicate with hearing persons. Videophones are also very useful to those with mobility issues or those who are located in distant places and are in need of telemedical or tele-educational services.

Descriptive names and terminology

Nortel 1535 IP model, have migrated away from slow POTS lines to higher speed ISDN and broadband VoIP services]]

The name videophone never became as standardized as its earlier counterpart telephone, resulting in a variety of names and terms being used worldwide, and even within the same region or country. Videophones are also known as video phones, videotelephones (or video telephones) and often by an early trademarked name Picturephone, which was the world's first commercial videophone produced in volume. The compound name videophone slowly entered into general use after 1950, although video telephone likely entered the lexicon earlier after video was coined in 1935.

Videophone calls (also: videocalls and video chat), differ from videoconferencing in that they expect to serve individuals, not groups. However that distinction has becoming increasingly blurred with technology improvements such as increased bandwidth and sophisticated software clients that can allow for multiple parties on a call. In general everyday usage the term videoconferencing is now frequently used instead of videocall for point-to-point calls between two units. Both videophone calls and videoconferencing are also now commonly referred to as a video link.

Webcams are popular, relatively low cost devices which can provide live video and audio streams via personal computers, and can be used with many software clients for both video calls and videoconferencing.

A videoconference system is generally higher cost than a videophone and deploys greater capabilities. A videoconference (also known as a videoteleconference) allows two or more locations to communicate via live, simultaneous two-way video and audio transmissions. This is often accomplished by the use of a multipoint control unit (a centralized distribution and call management system) or by a similar non-centralized multipoint capability embedded in each videoconferencing unit. Again, technology improvements have circumvented traditional definitions by allowing multiple party videoconferencing via web-based applications. A separate webpage article is devoted to videoconferencing.

A telepresence system is a high-end videoconferencing system and service usually employed by enterprise-level corporate offices. Telepresence conference rooms use state-of-the art room designs, video cameras, displays, sound-systems and processors, coupled with high-to-very-high capacity bandwidth transmissions.

Typical uses of the various technologies described above include videocalling or videoconferencing on a one-to-one, one-to-many or many-to-many basis for personal, business, educational, deaf Video Relay Service and tele-medical, diagnostic and rehabilitative use or services. New services utilizing videocalling and videoconferencing, such as personal videocalls to inmates incarcerated in penitentiaries, and videoconferencing to resolve airline engineering issues at maintenance facilities, are being created or evolving on an on-going basis.

Other names for videophone that have been used in English are: Viewphone (the British Telecom equivalent to AT&T;'s Picturephone), and visiophone, a common French translation that has also crept into limited English usage, as well as over twenty less common names and expressions. Latin-based translations of videophone in other languages include vidéophone' (French), bildtelefon (German), videotelefono (Italian), both videófono and videoteléfono (Spanish), both beeldtelefoon and videofoon (Dutch), and videofonía (Catalan).

Early history

and published in 1878. Note the use of then-contemporary speaking tubes by both the father in the foreground and his daughter on the viewing display.]]

Barely two years after the telephone was first patented in the United States, an early concept of a combined videophone/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 Edision. One such sketch was published 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 Alexander Graham Bell. Written under the pseudonym "Electrician", his article 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. In the era prior to the advent of broadcasting, electrical "seeing" devices were viewed as adjuncts to the telephone, thus creating the concept of a videophone.

In April 1891, Alexander Graham Bell did actually record conceptual notes on an electrical radiophone, which discussed "....the possibility of seeing by electricity" using devices that employed tellurium or selenium imaging components. Bell wrote, decades prior to the invention of the image dissector:

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."

The compound name videophone slowly entered into general usage after 1950,

One technological precursor to the videophone was the teleostereograph machine developed by AT&T;'s Bell Labs in the 1920s, which was a forerunner of today's fax (facsimile) machines. By 1927 AT&T; had created its earliest electromechanical videophone, called an ikonophone (Greek: image-sound), which operated at 18 frames per second and occupied half a room full of equipment cabinets. 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. By 1930, AT&T;'s 'two-way television-telephone' system was in experimental use;

First public video telephone service

The world's first public video telephone service was developed by Dr. Georg Schubert and opened by the German Reichspost in 1936 using square displays of , but which quickly closed in 1940 due to the outbreak of WWII. In that service trial, video telephone lines linked Berlin to Nuremberg, Munich, and Hamburg, with terminals integrated within public telephone booths and transmitting at the same resolution as the first German TV sets, at 440 lines. The service was offered to the general public who had to simultaneously visit special post office videotelephone booths in their respective cities, but at the same time also had Nazi political and propagandistic overtones similar to the broadcasting of the 1936 Olympic Games in Berlin.

The Deutsche Bundespost postal service would later develop and deploy its BIGFON (Broadband Integrated Glass-Fiber Optical Network) video telephony network from 1981 to 1988, serving several large German cities. The demonstration units usually used small oval housings on swivel stands, intended to stand on desks. Similar AT&T; Picturephone units were also featured at the Telephone Association of Canada Pavilion (the "Bell Pavilion") at Expo 67, an International World's Fair held in Montreal, Canada in 1967. Demonstration units were available at these fairs for the public to test, with fair-goers permitted to make videophone calls to volunteer recipients at other locations.

The United States would not see its first public video telephone booths until 1964, when AT&T; installed their earliest commercial videophone unit, the Picturephone Mod I, in public booths in three cities: New York, Washington, D.C. and Chicago. AT&T; concluded that its early videophone was a "concept looking for a market" and discontinued its Picturephone service in the late 1970s. again with very little commercial success.

Other early devices: 1968–1999

Beginning in the late 1960s, several countries worldwide sought to compete with AT&T;'s advanced development of their Picturephone in the United States. However such projects were research and capital intensive, and fraught with difficulties in being deployed commercially. In Sweden electronics maker Ericsson began developing one in the mid-1960s, intending to market them 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 in Stockholm. Ultimately Ericsson chose not to proceed with production.

In France, the defense and electronics manufacturer Matra was one of three French companies that sought to develop videophones in the early 1970s, spurred by the 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 in 1972. 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.

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.

In Japan the Lumaphone was developed and marketed by Atari and Mitsubishi in 1985. The project was started by the Ataritel division of the Atari Video Game Company in 1983 under the direction of Atari's Steve Bristow. Atari then sold its division to Mitsubishi in 1984. The Lumaphone was marketed by Mitsubishi Electric of America in 1986 as the Luma LU-1000. Similar to Bell Labs' very early image transfer phone of 1956, it could transmit still images every 3–5 seconds over analog POTS lines, and could also be connected to a regular TV or monitor for improved teleconferencing. A larger video image was available by attaching its optional VisiTel LU-500 display.

In the United States, the Intellect was a neo- or prototype wireless videophone, developed in 1993 by inventor Daniel A. Henderson, and which featured still image and non-live video clip transfers. The pioneering system and device were designed to receive pictures and video data sent from an originator to a message center for transmission and display to a wireless device such as a cellular telephone.

The Intellect was essentially a cell phone handset with a large black and white display that could show still images and video clips downloaded remotely from a computer via a wireless transmitter. The data transfer protocols pioneered in the Intellect design were later deployed with the common camera phones released in the early 2000s.

General lack of public acceptance

Early AT&T; Picturephones had few users, in part because the service was relatively expensive, with a service cost of approximately US$90 per month in 1974. However as modern technology reduced the costs to nominal (see: webcams), videophone calling continued to be used marginally. This contrasts to many early, overly optimistic views that videotelephony would become ubiquitous.

One reason may be that even today videophone calling is often a poor analog for direct face-to-face conversation. Videophone users also commonly look at the video screen and not at the video camera, preventing users from having direct eye-to-eye contact, as the video cameras are usually positioned away from the screen.

Another reason may be that some people actually desired less fidelity in their communication, as evidenced by the popularity of written conversation (i.e. texting and instant messaging, which are commonly available on all video-enabled cell phones and webchat programs). Additionally, others did not want to be seen at home—a videophone was viewed as an intrusion.

However it has also be noted that videotelephony is of great benefit to certain groups and demographics, such as members of a family living far apart and who may have a strong desire, but little opportunity for face-to-face conversations. Other groups that have strongly embraced videotelephony include those in the deaf community, where high quality video greatly facilitates sign language communications both within and outside of their personal and social settings.

Current usage

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The widest deployment of video telephony now occurs in mobile phones, as nearly all mobile phones supporting UMTS networks can work as videophones using their internal cameras, and are able to make video calls wirelessly to other UMTS users in the same country or internationally. As of the second quarter of 2007, there are over 131 million UMTS users (and hence potential videophone users), on 134 networks in 59 countries.

Videophones are increasingly used in the provision of telemedicine to the elderly and to those in remote locations, where the ease and convenience of quickly obtaining diagnostic and consultative medical services are readily apparent. In one single instance quoted in 2006: "A nurse-led clinic at Letham has received positive feedback on a trial of a video-link which allowed 60 pensioners to be assessed by medics without travelling to a doctor's office or medical clinic."

Videotelephony has also been deployed in corporate teleconferencing, also available through the use of public access videoconferencing rooms. A higher level of videoconferencing that employs advanced telecommunication technologies and high-resolution displays is called telepresence.

Today the principles, if not the precise mechanisms of a videophone are employed by many users worldwide in the form of webcam videocalls using personal computers, with inexpensive webcams, microphones and free videocalling web client programs. Thus an activity that was disappointing as a separate service has found a niche as a minor feature in software products intended for other purposes.

A videophone can also be created by using an old or inexpensive computer and dedicating it to run as a video softphone. This shows that some users may want to use conventional videophones, but are likely to trade ease of use for lower costs.

Some have argued that unless conventional videophones add considerable value at low cost, and as long as less expensive alternatives (such as webphones) are available, it will be unlikely that dedicated videophones will become popular.

According to Juniper Research, smartphone videophone users will reach 29 million by 2015 globally.

Sign language communications via videophones

Technology

Bandwidth requirements

Videophones have historically employed a variety of transmission and reception bandwidths, which can be understood as data transmission speeds. The lower the transmission/reception bandwidth, the lower the data transfer rate, resulting in a more limited and poorer image quality. Data transfer rates and live video image quality are related, but are also subject to other factors such as data compression techniques. Some early videophones employed very low data transmission rates with a resulting sketchy video quality.

Broadband bandwidth is often called "high-speed", because it usually has a high rate of data transmission. In general, any connection of 256 kbit/s (0.256 Mbit/s) or greater is more concisely considered broadband Internet. The International Telecommunication Union Standardization Sector (ITU-T) recommendation I.113 has defined broadband as a transmission capacity at 1.5 to 2 Mbit/s. The United States Federal Communications Commission definition of broadband is 768 kbit/s (0.8 Mbit/s).

Currently, adequate video for some purposes becomes possible at data rates lower than the ITU-T broadband definition, with rates of 768 kbit/s and 384 kbit/s used for some video conferencing applications, and rates as low as 100 kbit per second used for videophones using H.264/MPEG-4 AVC compression protocols. The newer MPEG-4 video and audio compression format can deliver high-quality video at 2 Mbit/s, which is at the low end of cable modem and ADSL broadband performance.

Picturephone technology

T-View 100 ISDN type videophone meant for home offices and small businesses with a lens cover which can be rotated upward to assure privacy when needed]]

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. 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. 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.

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.

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 kinds. Hundreds of technicians attended schools to learn to operate the Cable Equalizer Test Set and other equipment, and to install Picturephones.

AT&T later marketed the VideoPhone 2500 to the general public from 1992 to 1995. It was limited by analog phone line connection speeds of about 19 Kilobits per second, the video portion being 11,200 bits/s, and with a maximum frame rate of 10 frames per second, but typically much lower. The VideoPhone 2500 used proprietary technology protocols.

Call setup

Videoconferencing in the late 20th century was limited to the H.323 protocol (notably Cisco's SCCP implementation was an exception), but newer videophones often use SIP, which is often easier to set up in home networking environments. H.323 is still used, but more commonly for business videoconferencing, while SIP is more commonly used in personal consumer videophones. A number of call-setup methods based on instant messaging protocols such as Skype also now provide video. The principal open systems SIP source is Counterpath Corp., which provides support for British Telecom, Deutsche Telekom, Sprint, Telmex, AT&T;'s Callvantage, and the unified communicator of Cisco and Verizon.

Another protocol used by videophones is H.324, which mixes call setup and video compression. Videophones that work on regular phone lines typically use H.324, but the bandwidth is limited by the modem to around 33 kbit/s, limiting the video quality and frame rate. A slightly modified version of H.324 called 3G-324M defined by 3GPP is also used by some cellphones that allow video calls, typically for use only in UMTS networks.

There is also H.320 standard, which specified technical requirements for narrow-band visual telephone systems and terminal equipment, typically for videoconferencing and videophone services. It applied mostly to dedicated circuit-based switched network (point-to-point) connections of moderate or high bandwidth, such as through the medium-bandwidth ISDN digital phone protocol or a fractionated high bandwidth T1 lines. Modern products based on H.320 standard usually support also H.323 standard.

The IAX2 protocol also supports videophone calls natively, using the protocol's own capabilities to transport alternate media streams.

In popular culture

(1936): An early depiction of videotelephony as shown in the Charlie Chaplin movie, with an employee receiving instructions from a factory executive.]]

In many science fiction movies and TV programs that are set in the future, videophones are used as a primary method of communication. One of the first movies where a videophone was used was Fritz Lang’s Metropolis. Other famous examples of videophones include , , Star Trek, Total Recall, and Blade Runner. Of particular note, the videophone was a staple, everyday technology in the futuristic Hanna Barbera cartoon The Jetsons.

A portable videophone was featured prominently in the 2009 science fiction movie Moon, when the story's protagonist, Sam Bell, the supposedly lone occupant of a mining station on the far side of the Earth's moon, finally succeeds in making a live videocall to his home nearing the end of his extended work contract there, only to discover a shocking truth while talking with his daughter, whom he had never met.

Popular U.S. TV talk show hostess Oprah Winfrey incorporated videotelephony into her TV program on a regular basis from May 21, 2009, with an initial episode called Where the Skype Are You?, as part of a marketing agreement with the Internet telecommunication company Skype.

In science fiction literature, other names variously used for videophone include vidphone, vidfone, visiphone, and viewphone.

A device with the same functionality has been used by the comic strip character Dick Tracy since 1964. Called the "2-Way Wrist TV", the fictional detective often used the phone to communicate with police headquarters.

AT&T;'s VideoPhone 2500 prototypes are visible in the movie .

In the animated television program Futurama, the videophone is often used within the delivery service spaceship.

Videophones are occasionally used in the Pokémon anime.

A "Picturephone" is used in The Simpsons episode Lisa's Wedding.

A videophone was featured in the 1944 Warner Bros. cartoon, Plane Daffy, in which the female spy Hatta Mari used a videophone to communicate with Adolf Hitler.

In the British cartoon DangerMouse, where the title character regularly communicated with headquarters via videophones from both his home and his car.

The singer Beyoncé Knowles released a single called Video Phone from her 2008 album "I am... Sasha Fierce"

In Back to the Future Part II the future Marty McFly is contacted by Needles his coworker, and then by his boss Mr. Fujitsu via videophone.

In the Doctor Who Season 6 episode Day of the Moon, Canton Everett Delaware III, circa 1969, uses a video-capable cell phone supplied by Amy Pond to broadcast video of one of the Silents ranting in sync with Neil Armstrong's first steps on the Moon as part of Apollo 11.

See also

3GP

Information appliance

List of video telecommunication services and product brands

Media phone

Mobile VoIP

Smartphone

Teletraining

Tokbox

References

;Notes

;Bibliography

Daly, Edward A. & Hansell, Kathleen J. Visual Telephony, Artech House, Boston, 1999, ISBN 1-58053-023-0, ISBN 978-1-58053-023-1, CIPD HD9697.T452D35 651.7'3-dc21.

Nellist, John G. Understanding Telecommunications And Lightwave Systems: An Entry-Level Guide, John Wiley and Sons, IEEE Press, 2002, ISBN 0-471-15032-0, ISBN 978-0-471-15032-9.

Schnaars, Steve & Wymbs, Cliff. On The Persistence Of Lackluster Demand – The History Of The Video Telephone, Technological Forecasting and Social Change, March 2004, Vol.71, Issue 3, pp. 197–216. DOI: 10.1016/S0040-1625(02)00410-9. Viewable via ScienceDirect.com (subscription).

Shepard, Steven. Videoconferencing Demystified: Making Video Services Work, McGraw-Hill Professional, 2002, ISBN 0-07-140085-0, ISBN 978-0-07-140085-5

Stevenson Bacon, W. Amazing New Picturephone: A Step Closer to In-Person Visits, 'Popular Science, June 1968, pp. 46–47.

Wilcox, James R. & Gibson, David K. Video Communications: The Whole Picture, Focal Press, CMP Books, San Francisco, 2005, ISBN 1-57820-316-3, ISBN 978-1-57820-316-1.

Further reading

Being There, ProAV Magazine, 7 November 2008.

External links

Category:Assistive technology Category:Film and video technology Category:Health informatics Category:Smartphones Category:Technology in society Category:Telecommunication services Category:Teleconferencing Category:Video Category:Videotelephony