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A video camera is a camera used for the electronic recording of videos (as opposed to a movie camera, which records images on film). Video cameras were initially developed for the television industry but have since become widely used for a variety of other purposes.

A Flip video camera, formerly manufactured by Cisco.
President Barack Obama and Small Business Administration Administrator Karen Mills shown onscreen during an East Room event in the White House in 2009

Video cameras are used primarily in two modes. The first, characteristic of much early broadcasting, is live television, where the camera feeds real time images directly to a screen for immediate observation. A few cameras still serve live television production, but most live connections are for security, military/tactical, and industrial operations where surreptitious or remote viewing is required. In the second mode the images are recorded to a storage device for archiving or further processing; for many years, videotape was the primary format used for this purpose, but was gradually supplanted by optical disc, hard disk, and then flash memory. Recorded video is used in television production, and more often surveillance and monitoring tasks in which unattended recording of a situation is required for later analysis.

Contents

Modern video cameras have numerous designs and use:

The earliest video cameras were based on the mechanical Nipkow disk and used in experimental broadcasts through the 1910s–1930s. All-electronic designs based on the video camera tube, such as Vladimir Zworykin's Iconoscope and Philo Farnsworth's image dissector, supplanted the Nipkow system by the 1930s. These remained in wide use until the 1980s, when cameras based on solid-state image sensors such as the charge-coupled device (CCD) and later CMOS active-pixel sensor (CMOS sensor) eliminated common problems with tube technologies such as image burn-in and streaking and made digital video workflow practical, since the output of the sensor is digital so it does not need conversion from analog.

The basis for solid-state image sensors is metal-oxide-semiconductor (MOS) technology, which originates from the invention of the MOSFET (MOS field-effect transistor) at Bell Labs in 1959. This led to the development of semiconductor image sensors, including the CCD and later the CMOS active-pixel sensor. The first semiconductor image sensor was the charge-coupled device, invented at Bell Labs in 1969, based on MOS capacitor technology. The NMOS active-pixel sensor was later invented at Olympus in 1985, which led to the development of the CMOS active-pixel sensor at NASA's Jet Propulsion Laboratory in 1993.

Practical digital video cameras were also enabled by advances in video compression, due to the impractically high memory and bandwidth requirements of uncompressed video. The most important compression algorithm in this regard is the discrete cosine transform (DCT), a lossy compression technique that was first proposed in 1972. Practical digital video cameras were enabled by DCT-based video compression standards, including the H.26x and MPEG video coding standards introduced from 1988 onwards.

The transition to digital television gave a boost to digital video cameras. By the early 21st century, most video cameras were digital cameras.

With the advent of digital video capture, the distinction between professional video cameras and movie cameras has disappeared as the intermittent mechanism has become the same. Nowadays, mid-range cameras exclusively used for television and other work (except movies) are termed professional video cameras.

Early video could not be directly recorded. The first somewhat successful attempt to directly record video was in 1927 with John Logie Baird’s disc based Phonovision. The discs were unplayable with the technology of the time although later advances allowed the video to be recovered in the 1980s. The first experiments with using tape to record a video signal took place in 1951. The first commercially released system was Quadruplex videotape produced by Ampex in 1956. Two years later Ampex introduced a system capable of recording colour video. The first recording systems designed to be mobile (and thus usable outside the studio) were the Portapak systems starting with the Sony DV-2400 in 1967. This was followed in 1981 by the Betacam system where the tape recorder was built into the camera making a camcorder.

While some video cameras have built in lenses others use interchangeable lenses connected via a range of mounts. Some like Panavision PV and Arri PL are designed for movie cameras while others like Canon EF and Sony E come from still photography. A further set of mounts like S-mount exist for applications like CCTV.

  1. Williams, J. B. (2017). The Electronics Revolution: Inventing the Future. Springer. pp. 245–8. ISBN 9783319490885.
  2. "1960: Metal Oxide Semiconductor (MOS) Transistor Demonstrated". The Silicon Engine. Computer History Museum. RetrievedAugust 31, 2019.
  3. James R. Janesick (2001). Scientific charge-coupled devices. SPIE Press. pp. 3–4. ISBN 978-0-8194-3698-6.
  4. Matsumoto, Kazuya; et al. (1985). "A new MOS phototransistor operating in a non-destructive readout mode". Japanese Journal of Applied Physics. 24 (5A): L323. Bibcode:1985JaJAP..24L.323M. doi:10.1143/JJAP.24.L323.
  5. Fossum, Eric R. (12 July 1993). Blouke, Morley M. (ed.). "Active pixel sensors: are CCDs dinosaurs?". SPIE Proceedings Vol. 1900: Charge-Coupled Devices and Solid State Optical Sensors III. International Society for Optics and Photonics. 1900: 2–14. Bibcode:1993SPIE.1900....2F. CiteSeerX10.1.1.408.6558. doi:10.1117/12.148585. S2CID 10556755.
  6. Fossum, Eric R. (2007). "Active Pixel Sensors"(PDF). Semantic Scholar. S2CID 18831792. Archived from the original(PDF) on 9 March 2019. Retrieved8 October 2019.
  7. Fossum, Eric R.; Hondongwa, D. B. (2014). "A Review of the Pinned Photodiode for CCD and CMOS Image Sensors". IEEE Journal of the Electron Devices Society. 2 (3): 33–43. doi:10.1109/JEDS.2014.2306412.
  8. Belmudez, Benjamin (2014). Audiovisual Quality Assessment and Prediction for Videotelephony. Springer. pp. 11–13. ISBN 9783319141664.
  9. Huang, Hsiang-Cheh; Fang, Wai-Chi (2007). Intelligent Multimedia Data Hiding: New Directions. Springer. p. 41. ISBN 9783540711698.
  10. Ahmed, Nasir (January 1991). "How I Came Up With the Discrete Cosine Transform". Digital Signal Processing. 1 (1): 4–5. doi:10.1016/1051-2004(91)90086-Z.
  11. "'Phonovision': 1927-28 « the Dawn of TV".
  12. Marsh, Alex (27 July 2017). "A History of Videotape, Part 1". Bitstreams. Duke University. Retrieved11 February 2022.
  13. Buckingham, David; Willett, Rebekah; Pini, Maria (2011). Home Truths?: Video Production and Domestic Life. University of Michigan Press. p. 9. ISBN 9780472051373U.{{cite book}}:Check |isbn= value: invalid character ()
  14. Rhodes, Phil (4 February 2018). "The RedShark Guide to Lens Mounts". RedShark. Retrieved3 March 2022.

Video camera Article Talk Language Watch Edit A video camera is a camera used for the electronic recording of videos as opposed to a movie camera which records images on film Video cameras were initially developed for the television industry but have since become widely used for a variety of other purposes A Flip video camera formerly manufactured by Cisco President Barack Obama and Small Business Administration Administrator Karen Mills shown onscreen during an East Room event in the White House in 2009 Video cameras are used primarily in two modes The first characteristic of much early broadcasting is live television where the camera feeds real time images directly to a screen for immediate observation A few cameras still serve live television production but most live connections are for security military tactical and industrial operations where surreptitious or remote viewing is required In the second mode the images are recorded to a storage device for archiving or further processing for many years videotape was the primary format used for this purpose but was gradually supplanted by optical disc hard disk and then flash memory Recorded video is used in television production and more often surveillance and monitoring tasks in which unattended recording of a situation is required for later analysis Contents 1 Types and uses 2 History 3 Recording media 4 Lens mounts 5 See also 6 References 7 External linksTypes and uses EditModern video cameras have numerous designs and use Professional video cameras such as those used in television production maybe television studio based or mobile in the case of an electronic field production EFP Such cameras generally offer extremely fine grained manual control for the camera operator often to the exclusion of automated operation They usually use three sensors to separately record red green and blue Camcorders combine a camera and a VCR or other recording device in one unit these are mobile and were widely used for television production home movies electronic news gathering ENG including citizen journalism and similar applications Since the transition to digital video cameras most cameras have in built recording media and as such are also camcorders Action cameras often have 360 recording capabilities Closed circuit television CCTV generally uses pan tilt zoom cameras PTZ for security surveillance and or monitoring purposes Such cameras are designed to be small easily hidden and able to operate unattended those used in industrial or scientific settings are often meant for use in environments that are normally inaccessible or uncomfortable for humans and are therefore hardened for such hostile environments e g radiation high heat or toxic chemical exposure Webcams are video cameras that stream a live video feed to a computer Many smartphones have built in video cameras and even high end smartphones can capture video in 4K resolution Special camera systems are used for scientific research e g on board a satellite or a space probe in artificial intelligence and robotics research and in medical use Such cameras are often tuned for non visible radiation for infrared for night vision and heat sensing or X ray for medical and video astronomy use History EditThe earliest video cameras were based on the mechanical Nipkow disk and used in experimental broadcasts through the 1910s 1930s All electronic designs based on the video camera tube such as Vladimir Zworykin s Iconoscope and Philo Farnsworth s image dissector supplanted the Nipkow system by the 1930s These remained in wide use until the 1980s when cameras based on solid state image sensors such as the charge coupled device CCD and later CMOS active pixel sensor CMOS sensor eliminated common problems with tube technologies such as image burn in and streaking and made digital video workflow practical since the output of the sensor is digital so it does not need conversion from analog The basis for solid state image sensors is metal oxide semiconductor MOS technology 1 which originates from the invention of the MOSFET MOS field effect transistor at Bell Labs in 1959 2 This led to the development of semiconductor image sensors including the CCD and later the CMOS active pixel sensor 1 The first semiconductor image sensor was the charge coupled device invented at Bell Labs in 1969 3 based on MOS capacitor technology 1 The NMOS active pixel sensor was later invented at Olympus in 1985 4 5 6 which led to the development of the CMOS active pixel sensor at NASA s Jet Propulsion Laboratory in 1993 7 5 Practical digital video cameras were also enabled by advances in video compression due to the impractically high memory and bandwidth requirements of uncompressed video 8 The most important compression algorithm in this regard is the discrete cosine transform DCT 8 9 a lossy compression technique that was first proposed in 1972 10 Practical digital video cameras were enabled by DCT based video compression standards including the H 26x and MPEG video coding standards introduced from 1988 onwards 9 The transition to digital television gave a boost to digital video cameras By the early 21st century most video cameras were digital cameras With the advent of digital video capture the distinction between professional video cameras and movie cameras has disappeared as the intermittent mechanism has become the same Nowadays mid range cameras exclusively used for television and other work except movies are termed professional video cameras Recording media EditEarly video could not be directly recorded 11 The first somewhat successful attempt to directly record video was in 1927 with John Logie Baird s disc based Phonovision 11 The discs were unplayable with the technology of the time although later advances allowed the video to be recovered in the 1980s 11 The first experiments with using tape to record a video signal took place in 1951 12 The first commercially released system was Quadruplex videotape produced by Ampex in 1956 12 Two years later Ampex introduced a system capable of recording colour video 12 The first recording systems designed to be mobile and thus usable outside the studio were the Portapak systems starting with the Sony DV 2400 in 1967 13 This was followed in 1981 by the Betacam system where the tape recorder was built into the camera making a camcorder 13 Lens mounts EditWhile some video cameras have built in lenses others use interchangeable lenses connected via a range of mounts Some like Panavision PV and Arri PL are designed for movie cameras while others like Canon EF and Sony E come from still photography 14 A further set of mounts like S mount exist for applications like CCTV See also EditDigital movie camera Digital single lens reflex camera FireWire camera Professional video camera Recording at the edge Television production Three CCD Video camera tube Videograph Videotelephony Webcam Smart cameraReferences Edit a b c Williams J B 2017 The Electronics Revolution Inventing the Future Springer pp 245 8 ISBN 9783319490885 1960 Metal Oxide Semiconductor MOS Transistor Demonstrated The Silicon Engine Computer History Museum Retrieved August 31 2019 James R Janesick 2001 Scientific charge coupled devices SPIE Press pp 3 4 ISBN 978 0 8194 3698 6 Matsumoto Kazuya et al 1985 A new MOS phototransistor operating in a non destructive readout mode Japanese Journal of Applied Physics 24 5A L323 Bibcode 1985JaJAP 24L 323M doi 10 1143 JJAP 24 L323 a b Fossum Eric R 12 July 1993 Blouke Morley M ed Active pixel sensors are CCDs dinosaurs SPIE Proceedings Vol 1900 Charge Coupled Devices and Solid State Optical Sensors III International Society for Optics and Photonics 1900 2 14 Bibcode 1993SPIE 1900 2F CiteSeerX 10 1 1 408 6558 doi 10 1117 12 148585 S2CID 10556755 Fossum Eric R 2007 Active Pixel Sensors PDF Semantic Scholar S2CID 18831792 Archived from the original PDF on 9 March 2019 Retrieved 8 October 2019 Fossum Eric R Hondongwa D B 2014 A Review of the Pinned Photodiode for CCD and CMOS Image Sensors IEEE Journal of the Electron Devices Society 2 3 33 43 doi 10 1109 JEDS 2014 2306412 a b Belmudez Benjamin 2014 Audiovisual Quality Assessment and Prediction for Videotelephony Springer pp 11 13 ISBN 9783319141664 a b Huang Hsiang Cheh Fang Wai Chi 2007 Intelligent Multimedia Data Hiding New Directions Springer p 41 ISBN 9783540711698 Ahmed Nasir January 1991 How I Came Up With the Discrete Cosine Transform Digital Signal Processing 1 1 4 5 doi 10 1016 1051 2004 91 90086 Z a b c Phonovision 1927 28 the Dawn of TV a b c Marsh Alex 27 July 2017 A History of Videotape Part 1 Bitstreams Duke University Retrieved 11 February 2022 a b Buckingham David Willett Rebekah Pini Maria 2011 Home Truths Video Production and Domestic Life University of Michigan Press p 9 ISBN 9780472051373U a href wiki Template Cite book title Template Cite book cite book a Check isbn value invalid character help Rhodes Phil 4 February 2018 The RedShark Guide to Lens Mounts RedShark Retrieved 3 March 2022 External links Edit Media related to Video cameras at Wikimedia Commons The dictionary definition of video camera at Wiktionary Retrieved from https en wikipedia org w index php title Video camera amp oldid 1090686781, wikipedia, wiki, book,

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