Videophone
Encyclopedia
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
, webcam
s, 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.
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 become 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.
Webcam
s 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).
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, although video telephone likely entered the lexicon earlier after video was coined in 1935. 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.
Technological precursors to the videophone were the 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
, 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 (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. The New York City Bell Labs
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 telecommunications and broadcast entertainment purposes.
Reichspost
in 1936 using square displays of 8 inches (20.3 cm), 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.
's Bell Labs
conducted extensive research and development of videophones, leading to public demonstrations of its trademarked Picturephone product and service in the 1960s, including displays at the 1964 New York World's Fair
. 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 Pavilion (also called the "Bell Telephone 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. Picturephone booths were set up in New York's Grand Central Terminal
and elsewhere. With fanfare, Picturephones were also installed in offices of Westinghouse
in Pittsburgh, and at other progressive companies. However the use of reservation time slots and their initial cost of US$16 per three minute call at public booths greatly limited their appeal to the point that they were discontinued by 1968.
Unrelated difficulties at New York Telephone
also slowed AT&T's efforts, and few customers signed up for the service in either city. A CNN
report on 6 September 2001 stated that Picturephone service only had a total of 500 subscribers at its peak, and the service faded away in the 1970s. AT&T's initial Mod I and its upgraded Picturephone Mod II programs,, researched principally at its Bell Labs
, spanned 15 years and consumed US$500 million, eventually meeting with commercial failure. AT&T concluded that its early videophone was a "concept looking for a market" and discontinued its Picturephone service in the late 1970s. The research and development programs conducted by Bell Labs were highly notable for the beyond-the-state-of-the-art results produced in materials science
, advanced telecommunication
s, microelectronics and information technologies
.
Color on AT&T's Picturephone was not employed with their early models. These Picturephone units packaged Plumbicon cameras and small CRT
displays within their housings. The cameras were located atop their screens to help users see eye to eye. See this section for more information on Picturephone technology. Later generation display screens were larger than in the original demonstration units, approximately six inches (15 cm) square in a roughly cubical cabinet.
AT&T would then market its VideoPhone 2500 to the general public from 1992 to 1995 with prices starting at US$
1,500 and later dropping to $1,000, again with very little commercial success.
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 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. 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 phone
s released in the early 2000s. However, the complete integration of the cellular phone, digital camera and its wireless transmission infrastructure would take a few more years to complete. The prototype models were donated to the Smithsonian's National Museum of American History
in 2007.
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 videotelephony
costs to nominal, at least in the case of webcam
s, videophone calling continued to be only marginally utilized. This contrasts to many early, overly optimistic views that videotelephony would become ubiquitous.
There are several other reasons why videotelephony remains a peripheral telecommunications technology. One of the most important may be psychological: just as many people choose to listen to radio instead of watching television, individuals can prefer regular telephone conversations over videophone calls. This reason for poor acceptance may reflect that people can actually desire less fidelity in their communications. Additionally, others did not want to be seen at home—where a videophone can be viewed as too intrusive into one's private life. The reasoning and psychology can be summed as, although its true that "one picture can say a thousand words", its also true that, in poor situations, "one picture can say a thousand negative words".
Another reason may be that videophone calling can be a poor analog for direct face-to-face conversation. Videophone users 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. The issue of poor eye contact has been addressed on the more sophisticated videophone and videoconferencing
systems (as far back as the 1960s) by means of cameras hidden behind translucent display screens, directly inline with the projected image of the person being spoken to.
However it's also been observed that videotelephony is of great benefit to certain groups and demographics, such as members of families living far apart and who may have a strong desire, but little opportunity for face-to-face contact. Other groups that have 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
. The elderly and those who are physically immobile
also benefit from video telecommunications.
The widest deployment of video telephony now occurs in mobile phone
s, 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 pensioner
s to be assessed by medics without travelling to a doctor's office or medical clinic." A further improvement in telemedical services has been the development of new technology incorporated into special videophones to permit remote diagnostic services, such as blood sugar
level, blood pressure
and vital signs
monitoring. Such units are capable of relaying both regular audiovideo plus medical data over either standard (POTS
) telephone or newer broadband
lines.
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.
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.
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 pair
s 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 switch
es 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 bit/s, and with a maximum frame rate of 10 frames per second, but typically much lower. The VideoPhone 2500 used proprietary technology protocols.
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.
Telephone
The telephone , colloquially referred to as a phone, is a telecommunications device that transmits and receives sounds, usually the human voice. Telephones are a point-to-point communication system whose most basic function is to allow two people separated by large distances to talk to each other...
with a video screen, and is capable of full duplex
Duplex (telecommunications)
A duplex communication system is a system composed of two connected parties or devices that can communicate with one another in both directions. The term multiplexing is used when describing communication between more than two parties or devices....
(bi-directional) video
Video
Video is the technology of electronically capturing, recording, processing, storing, transmitting, and reconstructing a sequence of still images representing scenes in motion.- History :...
and audio
Sound
Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations.-Propagation of...
transmissions for communication between people in real-time. It was the first form of videotelephony
Videotelephony
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....
, later to be followed by videoconferencing
Videoconferencing
Videoconferencing is the conduct of a videoconference by a set of telecommunication technologies which allow two or more locations to interact via two-way video and audio transmissions simultaneously...
, webcam
Webcam
A webcam is a video camera that feeds its images in real time to a computer or computer network, often via USB, ethernet, or Wi-Fi.Their most popular use is the establishment of video links, permitting computers to act as videophones or videoconference stations. This common use as a video camera...
s, and finally telepresence
Telepresence
Telepresence refers to a set of technologies which allow a person to feel as if they were present, to give the appearance of being present, or to have an effect, via telerobotics, at a place other than their true location....
.
At the dawn of the technology, videotelephony also included image phones which would exchange still images between units every few seconds over conventional POTS
Plain old telephone service
Plain old telephone service is the voice-grade telephone service that remains the basic form of residential and small business service connection to the telephone network in many parts of the world....
-type telephone lines, essentially the same as slow scan TV
Slow-scan television
Slow-scan television is a picture transmission method used mainly by amateur radio operators, to transmit and receive static pictures via radio in monochrome or color.A technical term for SSTV is narrowband television...
systems.
Currently videophones are particularly useful to the deaf and speech-impaired
Speech disorder
Speech disorders or speech impediments are a type of communication disorders where 'normal' speech is disrupted. This can mean stuttering, lisps, etc. Someone who is unable to speak due to a speech disorder is considered mute.-Classification:...
who can use them with sign language
Sign language
A sign language is a language which, instead of acoustically conveyed sound patterns, uses visually transmitted sign patterns to convey meaning—simultaneously combining hand shapes, orientation and movement of the hands, arms or body, and facial expressions to fluidly express a speaker's...
, and also with video relay services
Video Relay Service
A Video Relay Service , also sometimes known as a Video Interpreting Service, is a videotelecommunication service that allows deaf, hard-of-hearing and speech-impaired individuals to communicate over video telephones and similar technologies with hearing people in real-time, via a sign language...
to communicate with hearing persons. Videophones are also very useful to those with mobility issues
Disability
A disability may be physical, cognitive, mental, sensory, emotional, developmental or some combination of these.Many people would rather be referred to as a person with a disability instead of handicapped...
or those who are located in distant places and are in need of telemedical
Telerehabilitation
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...
or tele-educational
Distance education
Distance education or distance learning is a field of education that focuses on teaching methods and technology with the aim of delivering teaching, often on an individual basis, to students who are not physically present in a traditional educational setting such as a classroom...
services.
Descriptive names and terminology
Videoconferencing
Videoconferencing is the conduct of a videoconference by a set of telecommunication technologies which allow two or more locations to interact via two-way video and audio transmissions simultaneously...
in that they expect to serve individuals, not groups. However that distinction has become increasingly blurred with technology improvements such as increased bandwidth
Broadband Internet access
Broadband Internet access, often shortened to just "broadband", is a high data rate, low-latency connection to the Internet— typically contrasted with dial-up access using a 56 kbit/s modem or satellite Internet with inherently high latency....
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.
Webcam
Webcam
A webcam is a video camera that feeds its images in real time to a computer or computer network, often via USB, ethernet, or Wi-Fi.Their most popular use is the establishment of video links, permitting computers to act as videophones or videoconference stations. This common use as a video camera...
s 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
Multipoint Control Unit
A Multipoint Control Unit is a device commonly used to bridge videoconferencing connections.The Multipoint Control Unit is an endpoint on the LAN that provides the capability for 3 or more terminals and gateways to participate in a multipoint conference...
(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
Videoconferencing
Videoconferencing is the conduct of a videoconference by a set of telecommunication technologies which allow two or more locations to interact via two-way video and audio transmissions simultaneously...
.
A telepresence system
Telepresence
Telepresence refers to a set of technologies which allow a person to feel as if they were present, to give the appearance of being present, or to have an effect, via telerobotics, at a place other than their true location....
is a high-end videoconferencing system and service usually employed by enterprise-level
Company
A company is a form of business organization. It is an association or collection of individual real persons and/or other companies, who each provide some form of capital. This group has a common purpose or focus and an aim of gaining profits. This collection, group or association of persons can be...
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
Video Relay Service
A Video Relay Service , also sometimes known as a Video Interpreting Service, is a videotelecommunication service that allows deaf, hard-of-hearing and speech-impaired individuals to communicate over video telephones and similar technologies with hearing people in real-time, via a sign language...
and tele-medical, diagnostic
Telemedicine
Telemedicine is the use of telecommunication and information technologies in order to provide clinical health care at a distance. It helps eliminate distance barriers and can improve access to medical services that would often not be consistently available in distant rural communities...
and rehabilitative
Telerehabilitation
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...
use or services. New services utilizing videocalling and videoconferencing, such as personal videocalls to inmates incarcerated in penitentiaries
Prison
A prison is a place in which people are physically confined and, usually, deprived of a range of personal freedoms. Imprisonment or incarceration is a legal penalty that may be imposed by the state for the commission of a crime...
, and videoconferencing to resolve airline engineering issues
Aircraft maintenance checks
Aircraft maintenance checks are periodic checks that have to be done on all aircraft after a certain amount of time or usage. Airlines and other commercial operators of large or turbine-powered aircraft follow a continuous inspection program approved by the Federal Aviation Administration in the...
at maintenance facilities
Hangar
A hangar is a closed structure to hold aircraft or spacecraft in protective storage. Most hangars are built of metal, but other materials such as wood and concrete are also sometimes used...
, 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
Telephonoscope
A telephonoscope was an early concept of videophone and television, conceptualized in the late 1870's through the 1890's. It was mentioned in various early science fiction works such as Le Vingtième siècle. La vie électrique and other works written by Albert Robida...
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
Le Vingtième siècle. La vie électrique
Le Vingtième siècle. La vie électrique is a science fiction novel written by the French author Albert Robida. It describes various aspects of life in France as it is supposed to take place in 1955. At the center of the plot are the scientific work and technological advances made by the illustrious...
(The 20th Century: The Electrical Life) and other works written by Albert Robida
Albert Robida
Albert Robida was an illustrator, etcher, lithographer, caricaturist, and novelist. He edited and published La Caricature magazine for 12 years. Through the 1880s he wrote an acclaimed trilogy of futuristic novels...
, and was also sketched in various cartoons by George du Maurier
George du Maurier
George Louis Palmella Busson du Maurier was a French-born British cartoonist and author, known for his cartoons in Punch and also for his novel Trilby. He was the father of actor Gerald du Maurier and grandfather of the writers Angela du Maurier and Dame Daphne du Maurier...
as a fictional invention of Thomas Edision. One such sketch was published on December 9, 1878 in Punch
Punch (magazine)
Punch, or the London Charivari was a British weekly magazine of humour and satire established in 1841 by Henry Mayhew and engraver Ebenezer Landells. Historically, it was most influential in the 1840s and 50s, when it helped to coin the term "cartoon" in its modern sense as a humorous illustration...
magazine.
The term telectroscope
Telectroscope
thumb|200px|right|Telectroscope technical illustration in [[Scientific American]] Supplement No. 275, April 9, 1881The telectroscope was the first non-working prototype of a television or videophone system...
was also used in 1878 by French writer and publisher Louis Figuier
Louis Figuier
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...
, to popularize an invention wrongly interpreted as real and incorrectly ascribed to Alexander Graham Bell
Alexander Graham Bell
Alexander Graham Bell was an eminent scientist, inventor, engineer and innovator who is credited with inventing the first practical telephone....
. 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
Broadcasting
Broadcasting is the distribution of audio and video content to a dispersed audience via any audio visual medium. Receiving parties may include the general public or a relatively large subset of thereof...
, 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
Selenium
Selenium is a chemical element with atomic number 34, chemical symbol Se, and an atomic mass of 78.96. It is a nonmetal, whose properties are intermediate between those of adjacent chalcogen elements sulfur and tellurium...
imaging components. Bell wrote, decades prior to the invention of the image dissector
Image dissector
An image dissector, also called a dissector tube, is a video camera tube in which photocathode emissions create an "electron image" which is then scanned to produce an electrical signal representing the visual image...
:
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, although video telephone likely entered the lexicon earlier after video was coined in 1935. 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.
Technological precursors to the videophone were the telegraphic image transmitters created by several companies, such as the wirephoto
Wirephoto
Wirephoto or telephotography is the sending of pictures by telegraph or telephone.Western Union transmitted its first halftone photograph in 1921. AT&T followed in 1924, and RCA sent a Radiophoto in 1926. The Associated Press began its Wirephoto service in 1935, and held a trademark on the term AP...
used by Western Union
Western Union
The Western Union Company is a financial services and communications company based in the United States. Its North American headquarters is in Englewood, Colorado. Up until 2006, Western Union was the best-known U.S...
, and the teleostereograph developed by AT&T's Bell Labs
Bell Labs
Bell Laboratories is the research and development subsidiary of the French-owned Alcatel-Lucent and previously of the American Telephone & Telegraph Company , half-owned through its Western Electric manufacturing subsidiary.Bell Laboratories operates its...
, which were forerunners of today's fax (facsimile) machines
Fax
Fax , sometimes called telecopying, is the telephonic transmission of scanned printed material , normally to a telephone number connected to a printer or other output device...
. 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
Mechanical television
Mechanical television was a broadcast television system that used mechanical or electromechanical devices to capture and display video images. However, the images themselves were usually transmitted electronically and via radio waves...
called the 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
Herbert Hoover
Herbert Clark Hoover was the 31st President of the United States . Hoover was originally a professional mining engineer and author. As the United States Secretary of Commerce in the 1920s under Presidents Warren Harding and Calvin Coolidge, he promoted partnerships between government and business...
address an audience in New York City
New York City
New York is the most populous city in the United States and the center of the New York Metropolitan Area, one of the most populous metropolitan areas in the world. New York exerts a significant impact upon global commerce, finance, media, art, fashion, research, technology, education, and...
from Washington, D.C.
Washington, D.C.
Washington, D.C., formally the District of Columbia and commonly referred to as Washington, "the District", or simply D.C., is the capital of the United States. On July 16, 1790, the United States Congress approved the creation of a permanent national capital as permitted by the U.S. Constitution....
; 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. The New York City Bell Labs
Bell Laboratories Building (Manhattan)
463 West Street is a 13 building complex located on the block between West Street, Washington Street, Bank Street, and Bethune Street in Manhattan, New York. It was originally the home of Bell Telephone Laboratories between 1898 and 1966. For a time, it was the largest industrial research center...
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 telecommunications and broadcast entertainment purposes.
First public video telephone service
The world's first public video telephone service was developed by Dr. Georg Schubert and opened by the GermanGermany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
Reichspost
Reichspost
- Imperial Reichspost :* The Imperial Reichspost was the name of the postal service of the Holy Roman Empire, founded by Franz von Taxis in 1495...
in 1936 using square displays of 8 inches (20.3 cm), but which quickly closed in 1940 due to the outbreak of WWII. In that service trial, video telephone lines linked Berlin
Berlin
Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...
to Nuremberg
Nuremberg
Nuremberg[p] is a city in the German state of Bavaria, in the administrative region of Middle Franconia. Situated on the Pegnitz river and the Rhine–Main–Danube Canal, it is located about north of Munich and is Franconia's largest city. The population is 505,664...
, Munich
Munich
Munich The city's motto is "" . Before 2006, it was "Weltstadt mit Herz" . Its native name, , is derived from the Old High German Munichen, meaning "by the monks' place". The city's name derives from the monks of the Benedictine order who founded the city; hence the monk depicted on the city's coat...
, and Hamburg
Hamburg
-History:The first historic name for the city was, according to Claudius Ptolemy's reports, Treva.But the city takes its modern name, Hamburg, from the first permanent building on the site, a castle whose construction was ordered by the Emperor Charlemagne in AD 808...
, 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
Propaganda
Propaganda is a form of communication that is aimed at influencing the attitude of a community toward some cause or position so as to benefit oneself or one's group....
overtones similar to the broadcasting of the 1936 Olympic Games in Berlin.
The Deutsche Bundespost
Deutsche Bundespost
The Deutsche Bundespost was created in 1947 as a successor to the Reichspost . Between 1947 and 1950 the enterprise was called Deutsche Post...
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.
AT&T Picturephone
In the United States AT&TAT&T
AT&T Inc. is an American multinational telecommunications corporation headquartered in Whitacre Tower, Dallas, Texas, United States. It is the largest provider of mobile telephony and fixed telephony in the United States, and is also a provider of broadband and subscription television services...
's Bell Labs
Bell Labs
Bell Laboratories is the research and development subsidiary of the French-owned Alcatel-Lucent and previously of the American Telephone & Telegraph Company , half-owned through its Western Electric manufacturing subsidiary.Bell Laboratories operates its...
conducted extensive research and development of videophones, leading to public demonstrations of its trademarked Picturephone product and service in the 1960s, including displays at the 1964 New York World's Fair
1964 New York World's Fair
The 1964/1965 New York World's Fair was the third major world's fair to be held in New York City. Hailing itself as a "universal and international" exposition, the fair's theme was "Peace Through Understanding," dedicated to "Man's Achievement on a Shrinking Globe in an Expanding Universe";...
. 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 Pavilion (also called the "Bell Telephone Pavilion") at Expo 67
Expo 67
The 1967 International and Universal Exposition or Expo 67, as it was commonly known, was the general exhibition, Category One World's Fair held in Montreal, Quebec, Canada, from April 27 to October 29, 1967. It is considered to be the most successful World's Fair of the 20th century, with the...
, an International World's Fair held in Montreal
Montreal
Montreal is a city in Canada. It is the largest city in the province of Quebec, the second-largest city in Canada and the seventh largest in North America...
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
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. Picturephone booths were set up in New York's Grand Central Terminal
Grand Central Terminal
Grand Central Terminal —often incorrectly called Grand Central Station, or shortened to simply Grand Central—is a terminal station at 42nd Street and Park Avenue in Midtown Manhattan in New York City, United States...
and elsewhere. With fanfare, Picturephones were also installed in offices of Westinghouse
Westinghouse Electric (1886)
Westinghouse Electric was an American manufacturing company. It was founded in 1886 as Westinghouse Electric Company and later renamed Westinghouse Electric Corporation by George Westinghouse. The company purchased CBS in 1995 and became CBS Corporation in 1997...
in Pittsburgh, and at other progressive companies. However the use of reservation time slots and their initial cost of US$16 per three minute call at public booths greatly limited their appeal to the point that they were discontinued by 1968.
Unrelated difficulties at New York Telephone
New York Telephone
The New York Telephone Company was organized in 1896, taking over the New York City operations of the American Bell Telephone Company.-Predecessor companies:...
also slowed AT&T's efforts, and few customers signed up for the service in either city. A CNN
CNN
Cable News Network is a U.S. cable news channel founded in 1980 by Ted Turner. Upon its launch, CNN was the first channel to provide 24-hour television news coverage, and the first all-news television channel in the United States...
report on 6 September 2001 stated that Picturephone service only had a total of 500 subscribers at its peak, and the service faded away in the 1970s. AT&T's initial Mod I and its upgraded Picturephone Mod II programs,, researched principally at its Bell Labs
Bell Labs
Bell Laboratories is the research and development subsidiary of the French-owned Alcatel-Lucent and previously of the American Telephone & Telegraph Company , half-owned through its Western Electric manufacturing subsidiary.Bell Laboratories operates its...
, spanned 15 years and consumed US$500 million, eventually meeting with commercial failure. AT&T concluded that its early videophone was a "concept looking for a market" and discontinued its Picturephone service in the late 1970s. The research and development programs conducted by Bell Labs were highly notable for the beyond-the-state-of-the-art results produced in materials science
Materials science
Materials science is an interdisciplinary field applying the properties of matter to various areas of science and engineering. This scientific field investigates the relationship between the structure of materials at atomic or molecular scales and their macroscopic properties. It incorporates...
, advanced telecommunication
Telecommunication
Telecommunication is the transmission of information over significant distances to communicate. In earlier times, telecommunications involved the use of visual signals, such as beacons, smoke signals, semaphore telegraphs, signal flags, and optical heliographs, or audio messages via coded...
s, microelectronics and information technologies
Information technology
Information technology is the acquisition, processing, storage and dissemination of vocal, pictorial, textual and numerical information by a microelectronics-based combination of computing and telecommunications...
.
Color on AT&T's Picturephone was not employed with their early models. These Picturephone units packaged Plumbicon cameras and small CRT
Cathode ray tube
The cathode ray tube is a vacuum tube containing an electron gun and a fluorescent screen used to view images. It has a means to accelerate and deflect the electron beam onto the fluorescent screen to create the images. The image may represent electrical waveforms , pictures , radar targets and...
displays within their housings. The cameras were located atop their screens to help users see eye to eye. See this section for more information on Picturephone technology. Later generation display screens were larger than in the original demonstration units, approximately six inches (15 cm) square in a roughly cubical cabinet.
AT&T would then market its VideoPhone 2500 to the general public from 1992 to 1995 with prices starting at US$
United States dollar
The United States dollar , also referred to as the American dollar, is the official currency of the United States of America. It is divided into 100 smaller units called cents or pennies....
1,500 and later dropping to $1,000, 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
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
electronics maker Ericsson
Ericsson
Ericsson , one of Sweden's largest companies, is a provider of telecommunication and data communication systems, and related services, covering a range of technologies, including especially mobile networks...
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
Stockholm
Stockholm is the capital and the largest city of Sweden and constitutes the most populated urban area in Scandinavia. Stockholm is the most populous city in Sweden, with a population of 851,155 in the municipality , 1.37 million in the urban area , and around 2.1 million in the metropolitan area...
. Ultimately Ericsson chose not to proceed with production.
In France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
, the defense and electronics manufacturer Matra
Matra
Mécanique Aviation Traction or Matra was a French company covering a wide range of activities mainly related to automobile, bicycles, aeronautics and weaponry. In 1994, it became a subsidiary of the Lagardère Group and now operates under that name.Matra was owned by the Floirat family...
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
Centre national d'études des télécommunications
CNET or Centre national d'études des télécommunications was a French national research centre in telecommunications....
(CNET of France Télécom
France Télécom
France Telecom S.A. is the main telecommunications company in France, the third-largest in Europe and one of the largest in the world. It currently employs about 180,000 people and has 192.7 million customers worldwide . In 2010 the group had revenue of €45.5 billion...
) 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
Videotelephony
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....
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.
Atari
Atari is a corporate and brand name owned by several entities since its inception in 1972. It is currently owned by Atari Interactive, a wholly owned subsidiary of the French publisher Atari, SA . The original Atari, Inc. was founded in 1972 by Nolan Bushnell and Ted Dabney. It was a pioneer in...
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
Mitsubishi Electric
is a multinational electronics and information technology company headquartered in Tokyo, Japan. It is one of the core companies of the Mitsubishi Group....
in 1986 as the Luma LU-1000. Similar to Bell Labs
Bell Labs
Bell Laboratories is the research and development subsidiary of the French-owned Alcatel-Lucent and previously of the American Telephone & Telegraph Company , half-owned through its Western Electric manufacturing subsidiary.Bell Laboratories operates its...
' very early image transfer phone of 1956, it could transmit still images every 3–5 seconds over analog POTS
Plain old telephone service
Plain old telephone service is the voice-grade telephone service that remains the basic form of residential and small business service connection to the telephone network in many parts of the world....
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 phone
Camera phone
A camera phone is a mobile phone which is able to capture still photographs . Since early in the 21st century the majority of mobile phones in use are camera phones....
s released in the early 2000s. However, the complete integration of the cellular phone, digital camera and its wireless transmission infrastructure would take a few more years to complete. The prototype models were donated to the Smithsonian's National Museum of American History
National Museum of American History
The National Museum of American History: Kenneth E. Behring Center collects, preserves and displays the heritage of the United States in the areas of social, political, cultural, scientific and military history. Among the items on display are the original Star-Spangled Banner and Archie Bunker's...
in 2007.
General lack of public acceptance
Early AT&TAT&T
AT&T Inc. is an American multinational telecommunications corporation headquartered in Whitacre Tower, Dallas, Texas, United States. It is the largest provider of mobile telephony and fixed telephony in the United States, and is also a provider of broadband and subscription television services...
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 videotelephony
Videotelephony
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....
costs to nominal, at least in the case of webcam
Webcam
A webcam is a video camera that feeds its images in real time to a computer or computer network, often via USB, ethernet, or Wi-Fi.Their most popular use is the establishment of video links, permitting computers to act as videophones or videoconference stations. This common use as a video camera...
s, videophone calling continued to be only marginally utilized. This contrasts to many early, overly optimistic views that videotelephony would become ubiquitous.
There are several other reasons why videotelephony remains a peripheral telecommunications technology. One of the most important may be psychological: just as many people choose to listen to radio instead of watching television, individuals can prefer regular telephone conversations over videophone calls. This reason for poor acceptance may reflect that people can actually desire less fidelity in their communications. Additionally, others did not want to be seen at home—where a videophone can be viewed as too intrusive into one's private life. The reasoning and psychology can be summed as, although its true that "one picture can say a thousand words", its also true that, in poor situations, "one picture can say a thousand negative words".
Another reason may be that videophone calling can be a poor analog for direct face-to-face conversation. Videophone users commonly look at the video screen and not at the video camera, preventing users from having direct eye-to-eye contact
Eye contact
Eye contact is a meeting of the eyes between two individuals.In human beings, eye contact is a form of nonverbal communication and is thought to have a large influence on social behavior. Coined in the early to mid-1960s, the term has come in the West to often define the act as a meaningful and...
, as the video cameras are usually positioned away from the screen. The issue of poor eye contact has been addressed on the more sophisticated videophone and videoconferencing
Videoconferencing
Videoconferencing is the conduct of a videoconference by a set of telecommunication technologies which allow two or more locations to interact via two-way video and audio transmissions simultaneously...
systems (as far back as the 1960s) by means of cameras hidden behind translucent display screens, directly inline with the projected image of the person being spoken to.
However it's also been observed that videotelephony is of great benefit to certain groups and demographics, such as members of families living far apart and who may have a strong desire, but little opportunity for face-to-face contact. Other groups that have embraced videotelephony include those in the deaf community where high quality video
High-definition video
High-definition video or HD video refers to any video system of higher resolution than standard-definition video, and most commonly involves display resolutions of 1,280×720 pixels or 1,920×1,080 pixels...
greatly facilitates sign language
Sign language
A sign language is a language which, instead of acoustically conveyed sound patterns, uses visually transmitted sign patterns to convey meaning—simultaneously combining hand shapes, orientation and movement of the hands, arms or body, and facial expressions to fluidly express a speaker's...
communications both within and outside of their personal and social settings
Video Relay Service
A Video Relay Service , also sometimes known as a Video Interpreting Service, is a videotelecommunication service that allows deaf, hard-of-hearing and speech-impaired individuals to communicate over video telephones and similar technologies with hearing people in real-time, via a sign language...
. The elderly and those who are physically immobile
Disability
A disability may be physical, cognitive, mental, sensory, emotional, developmental or some combination of these.Many people would rather be referred to as a person with a disability instead of handicapped...
also benefit from video telecommunications.
Current usage
Mobile phone
A mobile phone is a device which can make and receive telephone calls over a radio link whilst moving around a wide geographic area. It does so by connecting to a cellular network provided by a mobile network operator...
s, 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
Telemedicine
Telemedicine is the use of telecommunication and information technologies in order to provide clinical health care at a distance. It helps eliminate distance barriers and can improve access to medical services that would often not be consistently available in distant rural communities...
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 pensioner
Pensioner
In common parlance, a pensioner is a person who has retired, and now collects a pension. This is a term typically used in the United Kingdom and Australia where someone of pensionable age may also be referred to as an 'old age pensioner', or OAP. In the United States, the term retiree is more...
s to be assessed by medics without travelling to a doctor's office or medical clinic." A further improvement in telemedical services has been the development of new technology incorporated into special videophones to permit remote diagnostic services, such as blood sugar
Blood sugar
The blood sugar concentration or blood glucose level is the amount of glucose present in the blood of a human or animal. Normally in mammals, the body maintains the blood glucose level at a reference range between about 3.6 and 5.8 mM , or 64.8 and 104.4 mg/dL...
level, blood pressure
Blood pressure
Blood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...
and vital signs
Vital signs
Vital signs are measures of various physiological statistics, often taken by health professionals, in order to assess the most basic body functions. Vital signs are an essential part of a case presentation. The act of taking vital signs normally entails recording body temperature, pulse rate ,...
monitoring. Such units are capable of relaying both regular audiovideo plus medical data over either standard (POTS
Plain old telephone service
Plain old telephone service is the voice-grade telephone service that remains the basic form of residential and small business service connection to the telephone network in many parts of the world....
) telephone or newer broadband
Broadband
The term broadband refers to a telecommunications signal or device of greater bandwidth, in some sense, than another standard or usual signal or device . Different criteria for "broad" have been applied in different contexts and at different times...
lines.
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
Telepresence
Telepresence refers to a set of technologies which allow a person to feel as if they were present, to give the appearance of being present, or to have an effect, via telerobotics, at a place other than their true location....
.
Today the principles, if not the precise mechanisms of a videophone are employed by many users worldwide in the form of webcam
Webcam
A webcam is a video camera that feeds its images in real time to a computer or computer network, often via USB, ethernet, or Wi-Fi.Their most popular use is the establishment of video links, permitting computers to act as videophones or videoconference stations. This common use as a video camera...
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
Softphone
A softphone is a software program for making telephone calls over the Internet using a general purpose computer, rather than using dedicated hardware. Often a softphone is designed to behave like a traditional telephone, sometimes appearing as an image of a phone, with a display panel and buttons...
. 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
Bandwidth requirements
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
International Telecommunication Union
The International Telecommunication Union is the specialized agency of the United Nations which is responsible for information and communication technologies...
Standardization Sector (ITU-T
ITU-T
The ITU Telecommunication Standardization Sector is one of the three sectors of the International Telecommunication Union ; it coordinates standards for telecommunications....
) recommendation I.113 has defined broadband as a transmission capacity at 1.5 to 2 Mbit/s. The United States Federal Communications Commission
Federal Communications Commission
The Federal Communications Commission is an independent agency of the United States government, created, Congressional statute , and with the majority of its commissioners appointed by the current President. The FCC works towards six goals in the areas of broadband, competition, the spectrum, the...
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
MPEG-4
MPEG-4 is a method of defining compression of audio and visual digital data. It was introduced in late 1998 and designated a standard for a group of audio and video coding formats and related technology agreed upon by the ISO/IEC Moving Picture Experts Group under the formal standard ISO/IEC...
video and audio compression format can deliver high-quality video at 2 Mbit/s, which is at the low end of cable modem
Cable modem
A cable modem is a type of network bridge and modem that provides bi-directional data communication via radio frequency channels on a HFC and RFoG infrastructure. Cable modems are primarily used to deliver broadband Internet access in the form of cable Internet, taking advantage of the high...
and ADSL
Asymmetric Digital Subscriber Line
Asymmetric digital subscriber line is a type of digital subscriber line technology, a data communications technology that enables faster data transmission over copper telephone lines than a conventional voiceband modem can provide. It does this by utilizing frequencies that are not used by a voice...
broadband performance.
Picturephone technology
The Picturephone's video bandwidth was 1 MHz with a vertical scan rate of 30 Hz, horizontal scan rateHorizontal scan rate
Horizontal scan rate, or horizontal frequency, usually expressed in kilohertz, is the frequency at which a CRT moves the electron beam from the left side of the display to the right and back, and therefore describes the number of horizontal lines displayed per second...
of 8 kHz, and about 250 visible scan lines. The equipment included a Speakerphone
Speakerphone
A speakerphone is a telephone with a microphone and loudspeaker provided separately from those in the handset. This device allows multiple persons to participate in a conversation...
hands free telephone, with an added box to control picture transmission. Each Picturephone line used three twisted pair
Twisted pair
Twisted pair cabling is a type of wiring in which two conductors are twisted together for the purposes of canceling out electromagnetic interference from external sources; for instance, electromagnetic radiation from unshielded twisted pair cables, and crosstalk between neighboring pairs...
s 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
Equalization
Equalization, is the process of adjusting the balance between frequency components within an electronic signal. The most well known use of equalization is in sound recording and reproduction but there are many other applications in electronics and telecommunications. The circuit or equipment used...
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 switch
Crossbar switch
In electronics, a crossbar switch is a switch connecting multiple inputs to multiple outputs in a matrix manner....
es were designed and installed into the Bell System's
Bell System
The Bell System was the American Bell Telephone Company and then, subsequently, AT&T led system which provided telephone services to much of the United States and Canada from 1877 to 1984, at various times as a monopoly. In 1984, the company was broken up into separate companies, by a U.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 bit/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.323H.323
H.323 is a recommendation from the ITU Telecommunication Standardization Sector that defines the protocols to provide audio-visual communication sessions on any packet network...
protocol (notably Cisco's SCCP
Skinny Client Control Protocol
The Skinny Call Control Protocol is a proprietary network terminal control protocol originally developed by Selsius Systems....
implementation was an exception), but newer videophones often use SIP
Session Initiation Protocol
The Session Initiation Protocol is an IETF-defined signaling protocol widely used for controlling communication sessions such as voice and video calls over Internet Protocol . The protocol can be used for creating, modifying and terminating two-party or multiparty sessions...
, 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
Instant messaging
Instant Messaging is a form of real-time direct text-based chatting communication in push mode between two or more people using personal computers or other devices, along with shared clients. The user's text is conveyed over a network, such as the Internet...
protocols such as Skype
Skype
Skype is a software application that allows users to make voice and video calls and chat over the Internet. Calls to other users within the Skype service are free, while calls to both traditional landline telephones and mobile phones can be made for a fee using a debit-based user account system...
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
H.324
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....
, 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
3G-324M
3G-324M is the 3GPP umbrella protocol for video telephony in 3G mobile networks.The 3G-324M protocol operates over an established circuit switched connection between two...
defined by 3GPP
3GPP
The 3rd Generation Partnership Project is a collaboration between groups of telecommunications associations, known as the Organizational Partners...
is also used by some cellphones that allow video calls, typically for use only in UMTS networks.
There is also H.320
H.320
H.320 is an umbrella recommendation by the ITU-T for running Multimedia 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....
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
- In many science fictionScience fictionScience fiction is a genre of fiction dealing with imaginary but more or less plausible content such as future settings, futuristic science and technology, space travel, aliens, and paranormal abilities...
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’sFritz LangFriedrich Christian Anton "Fritz" Lang was an Austrian-American filmmaker, screenwriter, and occasional film producer and actor. One of the best known émigrés from Germany's school of Expressionism, he was dubbed the "Master of Darkness" by the British Film Institute...
MetropolisMetropolis (film)Metropolis is a 1927 German expressionist film in the science-fiction genre directed by Fritz Lang. Produced in Germany during a stable period of the Weimar Republic, Metropolis is set in a futuristic urban dystopia and makes use of this context to explore the social crisis between workers and...
. Other famous examples of videophones include 2001: A Space Odyssey2001: A Space Odyssey (film)2001: A Space Odyssey is a 1968 epic science fiction film produced and directed by Stanley Kubrick, and co-written by Kubrick and Arthur C. Clarke, partially inspired by Clarke's short story The Sentinel...
, Space: 1999Space: 1999Space: 1999 is a British science-fiction television series that ran for two seasons and originally aired from 1975 to 1977. In the opening episode, nuclear waste from Earth stored on the Moon's far side explodes in a catastrophic accident on 13 September 1999, knocking the Moon out of orbit and...
, Star TrekStar TrekStar Trek is an American science fiction entertainment franchise created by Gene Roddenberry. The core of Star Trek is its six television series: The Original Series, The Animated Series, The Next Generation, Deep Space Nine, Voyager, and Enterprise...
, Total RecallTotal RecallTotal Recall is a 1990 American science fiction action film. The film stars Arnold Schwarzenegger, Rachel Ticotin, Sharon Stone, Michael Ironside, Ronny Cox & Mel Johnson, Jr.. It is based on the Philip K. Dick story “We Can Remember It for You Wholesale”...
, and Blade RunnerBlade RunnerBlade Runner is a 1982 American science fiction film directed by Ridley Scott and starring Harrison Ford, Rutger Hauer, and Sean Young. The screenplay, written by Hampton Fancher and David Peoples, is loosely based on the novel Do Androids Dream of Electric Sheep? by Philip K...
. Of particular note, the videophone was a staple, everyday technology in the futuristic Hanna Barbera cartoon The JetsonsThe JetsonsThe Jetsons is a animated American sitcom that was produced by Hanna-Barbera, originally airing in prime-time from 1962–1963 and again from 1985–1987...
. - A portable videophone was featured prominently in the 2009 science fiction movie MoonMoon (film)Moon is a 2009 British science fiction drama film about a man who experiences a personal crisis as he nears the end of a three-year solitary stint mining helium-3 on the far side of the Earth's moon. It is the feature debut of director Duncan Jones. Sam Rockwell stars as the employee Sam Bell, and...
, 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 WinfreyOprah WinfreyOprah Winfrey is an American media proprietor, talk show host, actress, producer and philanthropist. Winfrey is best known for her self-titled, multi-award-winning talk show, which has become the highest-rated program of its kind in history and was nationally syndicated from 1986 to 2011...
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 SkypeSkypeSkype is a software application that allows users to make voice and video calls and chat over the Internet. Calls to other users within the Skype service are free, while calls to both traditional landline telephones and mobile phones can be made for a fee using a debit-based user account system...
. - 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 prototypePrototypeA prototype is an early sample or model built to test a concept or process or to act as a thing to be replicated or learned from.The word prototype derives from the Greek πρωτότυπον , "primitive form", neutral of πρωτότυπος , "original, primitive", from πρῶτος , "first" and τύπος ,...
s are visible in the movie Gremlins 2: The New BatchGremlins 2: The New BatchGremlins 2: The New Batch is a 1990 American horror comedy film, and the sequel to Gremlins . It was directed by Joe Dante and written by Charles S. Haas, with creature designs by Rick Baker...
. - In the animated television program FuturamaFuturamaFuturama is an American animated science fiction sitcom created by Matt Groening and developed by Groening and David X. Cohen for the Fox Broadcasting Company. The series follows the adventures of a late 20th-century New York City pizza delivery boy, Philip J...
, the videophone is often used within the delivery service spaceship. - Videophones are occasionally used in the Pokémon animePokémon (anime), abbreviated from , is a children's TV anime series, which has since been adapted for the North and South American, Australian and European television markets...
. - A "Picturephone" is used in The SimpsonsThe SimpsonsThe Simpsons is an American animated sitcom created by Matt Groening for the Fox Broadcasting Company. The series is a satirical parody of a middle class American lifestyle epitomized by its family of the same name, which consists of Homer, Marge, Bart, Lisa and Maggie...
episode Lisa's WeddingLisa's Wedding"Lisa's Wedding" is the 19th episode of The Simpsons sixth season, which originally aired March 19, 1995. The plot focuses around Lisa visiting a carnival fortune teller and learning about her future love. It was written by Greg Daniels and directed by Jim Reardon. Mandy Patinkin guest stars as...
. - A videophone was featured in the 1944 Warner Bros.Warner Bros.Warner Bros. Entertainment, Inc., also known as Warner Bros. Pictures or simply Warner Bros. , is an American producer of film and television entertainment.One of the major film studios, it is a subsidiary of Time Warner, with its headquarters in Burbank,...
cartoon, Plane DaffyPlane Daffy- Synopsis :One after another of a company of carrier pigeons fall prey to the seductive wiles of "Queen of the Spies" Hatta Mari. The alarm is raised at pigeon headquarters when Pigeon 13 goes AWOL with the female Nazi spy bird, to whom he reveals all his secrets...
, in which the female spy Hatta Mari used a videophone to communicate with Adolf HitlerAdolf HitlerAdolf Hitler was an Austrian-born German politician and the leader of the National Socialist German Workers Party , commonly referred to as the Nazi Party). He was Chancellor of Germany from 1933 to 1945, and head of state from 1934 to 1945...
. - In the BritishUnited KingdomThe United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
cartoon DangerMouseDangerMouseDanger Mouse is a British animated television series which was produced by Cosgrove Hall Films for Thames Television. It features the eponymous Danger Mouse, an English mouse who works as a superhero/secret agent. The show is a loose parody of British spy fiction, particularly James Bond and the...
, where the title character regularly communicated with headquarters via videophones from both his home and his car. - The singer Beyoncé KnowlesBeyoncé KnowlesBeyoncé Giselle Knowles , often known simply as Beyoncé, is an American singer, songwriter, record producer, and actress. Born and raised in Houston, Texas, she enrolled in various performing arts schools and was first exposed to singing and dancing competitions as a child...
released a single called Video Phone from her 2008 album "I am... Sasha Fierce" - In Back to the Future Part IIBack to the Future Part IIBack to the Future Part II is a 1989 American science fiction comedy film and the second installment of the Back to the Future trilogy. It was directed by Robert Zemeckis, written by Zemeckis and Bob Gale, and starred Michael J. Fox, Christopher Lloyd, Thomas F. Wilson and Lea Thompson...
the future Marty McFly is contacted by Needles his coworker, and then by his boss Mr. Fujitsu via videophone. - In the television series Pee-Wee's PlayhousePee-wee's PlayhousePee-wee's Playhouse is an American children's television program starring Paul Reubens as the child-like Pee-wee Herman. The show was developed from Reubens' popular stage show and the one-off TV special The Pee-wee Herman Show, produced for HBO, which was similar in style but featured much more...
, Pee-wee HermanPee-wee HermanPee-wee Herman is a comic fictional character created and portrayed by American comedian Paul Reubens. He is best known for his two television series and film series during the 1980s. The childlike Pee-wee Herman character developed as a stage act that quickly led to an HBO special in 1981...
often made and received calls on a "Picturephone".
See also
- 3GP3GP3GP is a multimedia container format defined by the Third Generation Partnership Project for 3G UMTS multimedia services. It is used on 3G mobile phones but can also be played on some 2G and 4G phones....
- Information applianceInformation applianceIn general terms, an information appliance or information device is any machine or device that is usable for the purposes of computing, telecommunicating, reproducing, and presenting encoded information in myriad forms and applications....
- List of video telecommunication services and product brands
- Media phoneMedia phoneThe media phone represents a new category of broadband multimedia device that has the potential to become the 4th screen in the home, complementing the PC, TV, and mobile phone handset.- Features :...
- Mobile VoIPMobile VoIPMobile VoIP or simply mVoIP is an extension of mobility to a Voice over IP network. Two types of communication are generally supported: cordless/DECT/PCS protocols for short range or campus communications where all base stations are linked into the same LAN, and wider area communications using...
- SmartphoneSmartphoneA smartphone is a high-end mobile phone built on a mobile computing platform, with more advanced computing ability and connectivity than a contemporary feature phone. The first smartphones were devices that mainly combined the functions of a personal digital assistant and a mobile phone or camera...
- TeletrainingTeletrainingTeletraining is training that# usually conveys live instruction via telecommunications facilities,# may be accomplished on a point-to-point basis or on a point-to-multipoint basis, and...
- TokboxTokboxTokBox provides a free API that allows anyone to add group video chat features to their own websites. Experienced programmers use the OpenTok API to build custom interactive video chat applications...
Further reading
- Being There, ProAV Magazine, 7 November 2008.