Video is an electronic medium for the recording, copying, playback,

broadcasting Broadcasting is the distribution of audio or video content to a dispersed audience via any electronic mass communications medium, but typically one using the electromagnetic spectrum (radio waves), in a one-to-many model. Broadcasting began ...

, and display of moving

visual The visual system comprises the sensory organ (the eye) and parts of the central nervous system (the retina containing photoreceptor cells, the optic nerve, the optic tract and the visual cortex) which gives organisms the sense of sight ...

media Media may refer to: Communication * Media (communication), tools used to deliver information or data ** Advertising media, various media, content, buying and placement for advertising ** Broadcast media, communications delivered over mass el ...

. Video was first developed for mechanical television systems, which were quickly replaced by

cathode-ray tube A cathode-ray tube (CRT) is a vacuum tube containing one or more electron guns, which emit electron beams that are manipulated to display images on a phosphorescent screen. The images may represent electrical waveforms ( oscilloscope), pi ...

(CRT) systems which, in turn, were replaced by

flat panel display A flat-panel display (FPD) is an electronic display used to display visual content such as text or images. It is present in consumer, medical, transportation, and industrial equipment. Flat-panel displays are thin, lightweight, provide better l ...

s of several types. Video systems vary in

display resolution The display resolution or display modes of a digital television, computer monitor or display device is the number of distinct pixels in each dimension that can be displayed. It can be an ambiguous term especially as the displayed resolution i ...

, aspect ratio,

refresh rate The refresh rate (or "vertical refresh rate", "vertical scan rate", terminology originating with the cathode ray tubes) is the number of times per second that a raster-based display device displays a new image. This is independent from frame ra ...

, color capabilities and other qualities. Analog and digital variants exist and can be carried on a variety of media, including radio broadcast,

magnetic tape Magnetic tape is a medium for magnetic storage made of a thin, magnetizable coating on a long, narrow strip of plastic film. It was developed in Germany in 1928, based on the earlier magnetic wire recording from Denmark. Devices that use mag ...

, optical discs, computer files, and network streaming.

History

Analog video

Video technology was first developed for mechanical television systems, which were quickly replaced by

(CRT)

television Television, sometimes shortened to TV, is a telecommunication Media (communication), medium for transmitting moving images and sound. The term can refer to a television set, or the medium of Transmission (telecommunications), television tra ...

systems, but several new technologies for video display devices have since been invented. Video was originally exclusively a live technology. Charles Ginsburg led an

Ampex Ampex is an American electronics company founded in 1944 by Alexander M. Poniatoff as a spin-off of Dalmo-Victor. The name AMPEX is a portmanteau, created by its founder, which stands for Alexander M. Poniatoff Excellence.AbramsoThe History ...

research team developing one of the first practical

video tape recorder A video tape recorder (VTR) is a tape recorder designed to record and playback video and audio material from magnetic tape. The early VTRs were open-reel devices that record on individual reels of 2-inch-wide (5.08 cm) tape. They were ...

s (VTR). In 1951, the first VTR captured live images from

television camera A professional video camera (often called a television camera even though its use has spread beyond television) is a high-end device for creating electronic moving images (as opposed to a movie camera, that earlier recorded the images on film). ...

s by writing the camera's electrical signal onto magnetic

videotape Videotape is magnetic tape used for storing video and usually sound in addition. Information stored can be in the form of either an analog or digital signal. Videotape is used in both video tape recorders (VTRs) and, more commonly, videocasse ...

. Video recorders were sold for US$50,000 in 1956, and videotapes cost US$300 per one-hour reel. However, prices gradually dropped over the years; in 1971, Sony began selling

videocassette recorder A videocassette recorder (VCR) or video recorder is an electromechanical device that records analog audio and analog video from broadcast television or other source on a removable, magnetic tape videocassette, and can play back the reco ...

(VCR) decks and tapes into the consumer market.

Digital video

Digital video is capable of higher quality and, eventually, much lower cost than earlier analog technology. After the invention of the DVD in 1997, and later the Blu-ray Disc in 2006, sales of videotape and recording equipment plummeted. Advances in computer technology allows even inexpensive

personal computer A personal computer (PC) is a multi-purpose microcomputer whose size, capabilities, and price make it feasible for individual use. Personal computers are intended to be operated directly by an end user, rather than by a computer expert or tech ...

s and

smartphone A smartphone is a portable computer device that combines mobile telephone and computing functions into one unit. They are distinguished from feature phones by their stronger hardware capabilities and extensive mobile operating systems, whic ...

s to capture, store, edit and transmit digital video, further reducing the cost of

video production Video production is the process of producing video content for video. It is the equivalent of filmmaking, but with video recorded either as analog signals on videotape, digitally in video tape or as computer files stored on optical discs, hard dri ...

, allowing program-makers and broadcasters to move to tapeless production. The advent of

digital broadcasting Digital broadcasting is the practice of using digital signals rather than analogue signals for broadcasting over radio frequency bands. Digital television broadcasting (especially satellite television) is widespread. Digital audio broadcasting ...

and the subsequent digital television transition is in the process of relegating analog video to the status of a legacy technology in most parts of the world. The development of high-resolution video cameras with improved dynamic range and color gamuts, along with the introduction of high-dynamic-range digital intermediate data formats with improved color depth, has caused digital video technology to converge with film technology. the usage of digital cameras in Hollywood has surpassed use of film cameras.

Characteristics of video streams

Number of frames per second

Frame rate Frame rate (expressed in or FPS) is the frequency (rate) at which consecutive images ( frames) are captured or displayed. The term applies equally to film and video cameras, computer graphics, and motion capture systems. Frame rate may also ...

'', the number of still pictures per unit of time of video, ranges from six or eight frames per second (''frame/s'') for old mechanical cameras to 120 or more frames per second for new professional cameras. PAL standards (Europe, Asia, Australia, etc.) and

SECAM SECAM, also written SÉCAM (, ''Séquentiel de couleur à mémoire'', French for ''color sequential with memory''), is an analog color television system that was used in France, some parts of Europe and Africa, and Russia. It was one of th ...

(France, Russia, parts of Africa etc.) specify 25 frame/s, while

NTSC The first American standard for analog television broadcast was developed by National Television System Committee (NTSC)National Television System Committee (1951–1953), Report and Reports of Panel No. 11, 11-A, 12–19, with Some supplement ...

standards (USA, Canada, Japan, etc.) specify 29.97 frame/s. Film is shot at the slower frame rate of 24 frames per second, which slightly complicates the process of transferring a cinematic motion picture to video. The minimum frame rate to achieve a comfortable illusion of a moving image is about sixteen frames per second.

Interlaced vs progressive

Video can be interlaced or

progressive Progressive may refer to: Politics * Progressivism, a political philosophy in support of social reform ** Progressivism in the United States, the political philosophy in the American context * Progressive realism, an American foreign policy par ...

. In progressive scan systems, each refresh period updates all scan lines in each frame in sequence. When displaying a natively progressive broadcast or recorded signal, the result is optimum spatial resolution of both the stationary and moving parts of the image. Interlacing was invented as a way to reduce flicker in early mechanical and

CRT CRT or Crt may refer to: Science, technology, and mathematics Medicine and biology * Calreticulin, a protein *Capillary refill time, for blood to refill capillaries *Cardiac resynchronization therapy and CRT defibrillator (CRT-D) * Catheter-re ...

video displays without increasing the number of complete frames per second. Interlacing retains detail while requiring lower bandwidth compared to progressive scanning. In interlaced video, the horizontal

scan line A scan line (also scanline) is one line, or row, in a raster scanning pattern, such as a line of video on a cathode ray tube (CRT) display of a television set or computer monitor. On CRT screens the horizontal scan lines are visually discerni ...

s of each complete frame are treated as if numbered consecutively, and captured as two ''fields'': an ''odd field'' (upper field) consisting of the odd-numbered lines and an ''even field'' (lower field) consisting of the even-numbered lines. Analog display devices reproduce each frame, effectively doubling the frame rate as far as perceptible overall flicker is concerned. When the image capture device acquires the fields one at a time, rather than dividing up a complete frame after it is captured, the frame rate for motion is effectively doubled as well, resulting in smoother, more lifelike reproduction of rapidly moving parts of the image when viewed on an interlaced CRT display. NTSC, PAL and SECAM are interlaced formats. Abbreviated video resolution specifications often include an ''i'' to indicate interlacing. For example, PAL video format is often described as ''576i50'', where ''576'' indicates the total number of horizontal scan lines, ''i'' indicates interlacing, and ''50'' indicates 50 fields (half-frames) per second. When displaying a natively interlaced signal on a progressive scan device, overall spatial resolution is degraded by simple line doubling—artifacts such as flickering or "comb" effects in moving parts of the image which appear unless special signal processing eliminates them. A procedure known as deinterlacing can optimize the display of an interlaced video signal from an analog, DVD or satellite source on a progressive scan device such as an LCD television, digital video projector or plasma panel. Deinterlacing cannot, however, produce video quality that is equivalent to true progressive scan source material.

Aspect ratio

Aspect ratio describes the proportional relationship between the width and height of video screens and video picture elements. All popular video formats are rectangular, and so can be described by a ratio between width and height. The ratio width to height for a traditional television screen is 4:3, or about 1.33:1. High definition televisions use an aspect ratio of 16:9, or about 1.78:1. The aspect ratio of a full 35 mm film frame with soundtrack (also known as the Academy ratio) is 1.375:1.

Pixel In digital imaging, a pixel (abbreviated px), pel, or picture element is the smallest addressable element in a raster image, or the smallest point in an all points addressable display device. In most digital display devices, pixels are the s ...

s on computer monitors are usually square, but pixels used in digital video often have non-square aspect ratios, such as those used in the PAL and NTSC variants of the CCIR 601 digital video standard, and the corresponding anamorphic widescreen formats. The 720 by 480 pixel raster uses thin pixels on a 4:3 aspect ratio display and fat pixels on a 16:9 display. The popularity of viewing video on mobile phones has led to the growth of vertical video. Mary Meeker, a partner at Silicon Valley venture capital firm Kleiner Perkins Caufield & Byers, highlighted the growth of vertical video viewing in her 2015 Internet Trends Report growing from 5% of video viewing in 2010 to 29% in 2015. Vertical video ads like Snapchat’s are watched in their entirety nine times more frequently than landscape video ads.

Color model and depth

The color model the video color representation and maps encoded color values to visible colors reproduced by the system. There are several such representations in common use: typically YIQ is used in NTSC television, YUV is used in PAL television, YDbDr is used by SECAM television and

YCbCr YCbCr, Y′CbCr, or Y Pb/Cb Pr/Cr, also written as YCBCR or Y′CBCR, is a family of color spaces used as a part of the color image pipeline in video and digital photography systems. Y′ is the Luma (video), luma component and CB and CR are t ...

is used for digital video. The number of distinct colors a pixel can represent depends on color depth expressed in the number of bits per pixel. A common way to reduce the amount of data required in digital video is by chroma subsampling (e.g., 4:4:4, 4:2:2, etc.). Because the human eye is less sensitive to details in color than brightness, the luminance data for all pixels is maintained, while the chrominance data is averaged for a number of pixels in a block and that same value is used for all of them. For example, this results in a 50% reduction in chrominance data using 2-pixel blocks (4:2:2) or 75% using 4-pixel blocks (4:2:0). This process does not reduce the number of possible color values that can be displayed, but it reduces the number of distinct points at which the color changes.

Video quality

Video quality can be measured with formal metrics like Peak signal-to-noise ratio (PSNR) or through subjective video quality assessment using expert observation. Many subjective video quality methods are described in the

ITU-T The ITU Telecommunication Standardization Sector (ITU-T) is one of the three sectors (divisions or units) of the International Telecommunication Union (ITU). It is responsible for coordinating standards for telecommunications and Information Commu ...

recommendation BT.500. One of the standardized methods is the ''Double Stimulus Impairment Scale'' (DSIS). In DSIS, each expert views an ''unimpaired'' reference video followed by an ''impaired'' version of the same video. The expert then rates the ''impaired'' video using a scale ranging from "impairments are imperceptible" to "impairments are very annoying".

Video compression method (digital only)

Uncompressed video delivers maximum quality, but at a very high

data rate Data rate and data transfer rate can refer to several related and overlapping concepts in communications networks: Achieved rate * Bit rate, the number of bits that are conveyed or processed per unit of time ** Data signaling rate or gross bit rate ...

. A variety of methods are used to compress video streams, with the most effective ones using a group of pictures (GOP) to reduce spatial and temporal redundancy. Broadly speaking, spatial redundancy is reduced by registering differences between parts of a single frame; this task is known as '' intraframe compression'' and is closely related to image compression. Likewise, temporal redundancy can be reduced by registering differences between frames; this task is known as '' interframe compression'', including motion compensation and other techniques. The most common modern compression standards are

MPEG-2 MPEG-2 (a.k.a. H.222/H.262 as was defined by the ITU) is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods, w ...

, used for DVD,

Blu-ray The Blu-ray Disc (BD), often known simply as Blu-ray, is a digital optical disc data storage format. It was invented and developed in 2005 and released on June 20, 2006 worldwide. It is designed to supersede the DVD format, and capable of s ...

and satellite television, and

MPEG-4 MPEG-4 is a group of international standards for the compression of digital audio and visual data, multimedia systems, and file storage formats. It was originally introduced in late 1998 as a group of audio and video coding formats and related ...

, used for AVCHD, Mobile phones (3GP) and Internet.

Stereoscopic

Stereoscopic video for

3d film 3D films are motion pictures made to give an illusion of Three-dimensional space, three-dimensional solidity, usually with the help of Stereoscopy#3D viewers, special glasses worn by viewers. They have existed in some form since 1915, but had been ...

and other applications can be displayed using several different methods: * Two channels: a right channel for the right eye and a left channel for the left eye. Both channels may be viewed simultaneously by using light-polarizing filters 90 degrees off-axis from each other on two video projectors. These separately polarized channels are viewed wearing eyeglasses with matching polarization filters. * Anaglyph 3D where one channel is overlaid with two color-coded layers. This left and right layer technique is occasionally used for network broadcast or recent anaglyph releases of 3D movies on DVD. Simple red/cyan plastic glasses provide the means to view the images discretely to form a stereoscopic view of the content. * One channel with alternating left and right frames for the corresponding eye, using LCD shutter glasses that synchronize to the video to alternately block the image to each eye, so the appropriate eye sees the correct frame. This method is most common in computer

virtual reality Virtual reality (VR) is a simulated experience that employs pose tracking and 3D near-eye displays to give the user an immersive feel of a virtual world. Applications of virtual reality include entertainment (particularly video games), e ...

applications such as in a Cave Automatic Virtual Environment, but reduces effective video framerate by a factor of two.

Formats

Different layers of video transmission and storage each provide their own set of formats to choose from. For transmission, there is a physical connector and signal protocol (see List of video connectors). A given physical link can carry certain display standards that specify a particular refresh rate,

, and

color space A color space is a specific organization of colors. In combination with color profiling supported by various physical devices, it supports reproducible representations of colorwhether such representation entails an analog or a digital representa ...

. Many analog and digital recording formats are in use, and digital video clips can also be stored on a computer file system as files, which have their own formats. In addition to the physical format used by the data storage device or transmission medium, the stream of ones and zeros that is sent must be in a particular digital

video coding format A video coding format (or sometimes video compression format) is a content representation format for storage or transmission of digital video content (such as in a data file or bitstream). It typically uses a standardized video compression alg ...

, of which a number are available.

Analog video

Analog video is a video signal represented by one or more

analog signal An analog signal or analogue signal (see spelling differences) is any continuous signal representing some other quantity, i.e., ''analogous'' to another quantity. For example, in an analog audio signal, the instantaneous signal voltage vari ...

s. Analog color video signals include luminance, brightness (Y) and chrominance (C). When combined into one channel, as is the case, among others with

, PAL and

it is called

composite video Composite video is an analog video signal format that carries standard-definition video (typically at 525 lines or 625 lines) as a single channel. Video information is encoded on one channel, unlike the higher-quality S-Video (two channe ...

. Analog video may be carried in separate channels, as in two channel

S-Video S-Video (also known as separate video, Y/C, and erroneously Super-Video ) is an analog video signal format that carries standard-definition video, typically at 525 lines or 625 lines. It encodes video luma and chrominance on two separate chan ...

(YC) and multi-channel

component video Component video is an analog video signal that has been split into two or more component channels. In popular use, it refers to a type of component analog video (CAV) information that is transmitted or stored as three separate signals. Compo ...

formats. Analog video is used in both consumer and professional television production applications. Composite-video-cable.jpg,

Composite video Composite video is an analog video signal format that carries standard-definition video (typically at 525 lines or 625 lines) as a single channel. Video information is encoded on one channel, unlike the higher-quality S-Video (two channe ...

(single channel RCA) Close-up_of_S-video_female_connector.jpg,

(2-channel YC) Component-cables.jpg,

Component video Component video is an analog video signal that has been split into two or more component channels. In popular use, it refers to a type of component analog video (CAV) information that is transmitted or stored as three separate signals. Compo ...

(3-channel

YPbPr YPbPr or Y'PbPr, also written as , is a color space used in video electronics, in particular in reference to component video cables. YPBPR is gamma corrected YCBCR color space (it is not analog YUV that was used for analog TV, though componen ...

) SCART_20050724_002.jpg,

SCART SCART (also known as or , especially in France, 21-pin EuroSCART in marketing by Sharp in Asia, Euroconector in Spain, EuroAV or EXT, or EIA Multiport in the United States, as an EIA interface) is a French-originated standard and associated 2 ...

Vga-cable.jpg, VGA 3.5mm.jpg,

TRRS A phone connector, also known as phone jack, audio jack, headphone jack or jack plug, is a family of electrical connectors typically used for analog signal, analog audio signals. A plug, the Gender of connectors and fasteners, male connect ...

D4_video_connector.jpg, D-Terminal

Digital video

Digital video signal formats have been adopted, including serial digital interface (SDI),

Digital Visual Interface Digital Visual Interface (DVI) is a video display interface developed by the Digital Display Working Group (DDWG). The digital interface is used to connect a video source, such as a video display controller, to a display device, such as a co ...

(DVI), High-Definition Multimedia Interface (HDMI) and

DisplayPort DisplayPort (DP) is a digital display interface developed by a consortium of PC and chip manufacturers and standardized by the Video Electronics Standards Association (VESA). It is primarily used to connect a video source to a display device su ...

Interface. BNC_connector_%28male%29.jpg, Serial digital interface (SDI) Dvi-cable.jpg,

(DVI) HDMI-Connector.jpg,

HDMI High-Definition Multimedia Interface (HDMI) is a proprietary audio/video interface for transmitting uncompressed video data and compressed or uncompressed digital audio data from an HDMI-compliant source device, such as a display controll ...

Displayport-cable.jpg,

Transport medium

Video can be transmitted or transported in a variety of ways including wireless

terrestrial television Terrestrial television or over-the-air television (OTA) is a type of television broadcasting in which the signal transmission occurs via radio waves from the terrestrial (Earth-based) transmitter of a television station, TV station to a televis ...

as an analog or digital signal, coaxial cable in a closed-circuit system as an analog signal. Broadcast or studio cameras use a single or dual coaxial cable system using serial digital interface (SDI). See List of video connectors for information about physical connectors and related signal standards. Video may be transported over networks and other shared digital communications links using, for instance, MPEG transport stream, SMPTE 2022 and SMPTE 2110.

Display standards

Digital television

Digital television Digital television (DTV) is the transmission of television signals using digital encoding, in contrast to the earlier analog television technology which used analog signals. At the time of its development it was considered an innovative advanc ...

broadcasts use the

and other

s and include: * ATSC – United States,

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tota ...

Mexico Mexico ( Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guate ...

Korea Korea ( ko, 한국, or , ) is a peninsular region in East Asia. Since 1945, it has been divided at or near the 38th parallel, with North Korea (Democratic People's Republic of Korea) comprising its northern half and South Korea (Republi ...

* Digital Video Broadcasting (DVB) –

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located enti ...

* ISDB – Japan ** ISDB-Tb – uses the MPEG-4 video coding format –

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, t ...

* Digital Multimedia Broadcasting (DMB) –

Analog television

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

broadcast standards include: * Field-sequential color system (FCS) – US, Russia; obsolete * Multiplexed Analogue Components (MAC) – Europe; obsolete * Multiple sub-Nyquist sampling encoding (MUSE) – Japan *

–

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

, Japan ** EDTV-II "Clear-Vision" - NTSC extension, Japan * PAL –

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an ...

Oceania Oceania (, , ) is a region, geographical region that includes Australasia, Melanesia, Micronesia, and Polynesia. Spanning the Eastern Hemisphere, Eastern and Western Hemisphere, Western hemispheres, Oceania is estimated to have a land area of ...

** PAL-M – PAL variation,

** PAL-N – PAL variation,

Paraguay Paraguay (; ), officially the Republic of Paraguay ( es, República del Paraguay, links=no; gn, Tavakuairetã Paraguái, links=si), is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to th ...

and

Uruguay Uruguay (; ), officially the Oriental Republic of Uruguay ( es, República Oriental del Uruguay), is a country in South America. It shares borders with Argentina to its west and southwest and Brazil to its north and northeast; while bordering ...

** PALplus – PAL extension,

* RS-343 (military) *

–

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan ar ...

, former

Soviet Union The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...

Central Africa Central Africa is a subregion of the African continent comprising various countries according to different definitions. Angola, Burundi, the Central African Republic, Chad, the Democratic Republic of the Congo, the Republic of the Congo, E ...

* CCIR System A * CCIR System B * CCIR System G * CCIR System H * CCIR System I *

CCIR System M CCIR System M, sometimes called 525–line, monochrome NTSC or NTSC-M, is the analog broadcast television system approved by the FCC (upon recommendation by the National Television Systems Committee - NTSC) for use in the United States since ...

An analog video format consists of more information than the visible content of the frame. Preceding and following the image are lines and pixels containing metadata and synchronization information. This surrounding margin is known as a ''blanking interval'' or ''blanking region''; the horizontal and vertical front porch and back porch are the building blocks of the blanking interval.

Computer displays

Computer display standards specify a combination of aspect ratio, display size, display resolution, color depth, and refresh rate. A list of common resolutions is available.

Recording

Early television was almost exclusively a live medium with some programs recorded to film for distribution of historical purposes using

Kinescope Kinescope , shortened to kine , also known as telerecording in Britain, is a recording of a television program on motion picture film, directly through a lens focused on the screen of a video monitor. The process was pioneered during the 1940 ...

. The analog

was commercially introduced in 1951. The following list is in rough chronological order. All formats listed were sold to and used by broadcasters, video producers or consumers; or were important historically. *

2" Quadruplex videotape 2-inch quadruplex videotape (also called 2″ quad video tape or quadraplex) was the first practical and commercially successful analog recording video tape format. It was developed and released for the broadcast television industry in 1956 by A ...

(

1956) *

VERA Vera may refer to: Names *Vera (surname), a surname (including a list of people with the name) *Vera (given name), a given name (including a list of people and fictional characters with the name) **Vera (), archbishop of the archdiocese of Tarrag ...

( BBC experimental format ca. 1958) * 1" Type A videotape (

) * 1/2" EIAJ (1969) * U-matic 3/4" (

Sony , commonly stylized as SONY, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. As a major technology company, it operates as one of the world's largest manufacturers of consumer and professional ...

) * 1/2" Cartrivision ( Avco) * VCR, VCR-LP, SVR * 1" Type B videotape ( Robert Bosch GmbH) * 1" Type C videotape (

, Marconi and

) * Betamax (Sony) * VHS ( JVC) * Video 2000 (

Philips Koninklijke Philips N.V. (), commonly shortened to Philips, is a Dutch multinational conglomerate corporation that was founded in Eindhoven in 1891. Since 1997, it has been mostly headquartered in Amsterdam, though the Benelux headquarters is ...

) * 2" Helical Scan Videotape ( IVC) * 1/4" CVC (

Funai is a Japanese consumer electronics company headquartered in Daitō, Osaka. Apart from producing its own branded electronic products, it is also an OEM providing assembled televisions and video players/recorders to major corporations such as ...

) * Betacam (Sony) *

HDVS Sony HDVS is a range of high-definition video equipment developed in the 1980s to support an early analog high-definition television system (used in multiple sub-Nyquist sampling encoding (MUSE) broadcasts) thought to be the broadcast televisio ...

(Sony) * Betacam SP (Sony) * Video8 (

) (1986) * S-VHS ( JVC) (1987) * VHS-C ( JVC) * Pixelvision ( Fisher-Price) * UniHi 1/2" HD (Sony) * Hi8 (Sony) (mid-1990s) * W-VHS ( JVC) (1994) Digital video tape recorders offered improved quality compared to analog recorders. * Betacam IMX (

) * D-VHS ( JVC) * D-Theater * D1 (

) * D2 (

) * D3 * D5 HD * D6 (

) * Digital-S D9 ( JVC) * Digital Betacam (

) * Digital8 (

) * DV (including DVC-Pro) * HDCAM (

) * HDV * ProHD ( JVC) * MicroMV * MiniDV Optical storage mediums offered an alternative, especially in consumer applications, to bulky tape formats. * Blu-ray Disc (

) * China Blue High-definition Disc (CBHD) * DVD (was

Super Density Disc The DVD (common abbreviation for Digital Video Disc or Digital Versatile Disc) is a digital media, digital optical disc data storage format. It was invented and developed in 1995 and first released on November 1, 1996, in Japan. The medium can ...

, DVD Forum) * Professional Disc * Universal Media Disc (UMD) (

) * Enhanced Versatile Disc (EVD, Chinese government-sponsored) *

HD DVD HD DVD (short for High Definition Digital Versatile Disc) is an obsolete high-density optical disc format for storing data and playback of high-definition video. Supported principally by Toshiba, HD DVD was envisioned to be the successor to ...

( NEC and Toshiba) * HD-VMD * Capacitance Electronic Disc * Laserdisc (

MCA MCA may refer to: Astronomy * Mars-crossing asteroid, an asteroid whose orbit crosses that of Mars Aviation * Minimum crossing altitude, a minimum obstacle crossing altitude for fixes on published airways * Medium Combat Aircraft, a 5th gene ...

and

) * Television Electronic Disc ( Teldec and

Telefunken Telefunken was a German radio and television apparatus company, founded in Berlin in 1903, as a joint venture of Siemens & Halske and the ''Allgemeine Elektrizitäts-Gesellschaft'' (AEG) ('General electricity company'). The name "Telefunken" app ...

) * VHD ( JVC)

Digital encoding formats

A video codec is

software Software is a set of computer programs and associated software documentation, documentation and data (computing), data. This is in contrast to Computer hardware, hardware, from which the system is built and which actually performs the work. ...

or hardware that compresses and decompresses digital video. In the context of video compression, ''

codec A codec is a device or computer program that encodes or decodes a data stream or signal. ''Codec'' is a portmanteau of coder/decoder. In electronic communications, an endec is a device that acts as both an encoder and a decoder on a signal or ...

'' is a

portmanteau A portmanteau word, or portmanteau (, ) is a blend of wordsencoder Encoder may refer to: Electronic circuits * Audio encoder, converts digital audio to analog audio signals * Video encoder, converts digital video to analog video signals * Simple encoder, assigns a binary code to an active input line * Priority e ...

'', and one that only decompresses is a ''decoder''. The compressed data format usually conforms to a standard

. The compression is typically lossy, meaning that the compressed video lacks some information present in the original video. A consequence of this is that decompressed video has lower quality than the original, uncompressed video because there is insufficient information to accurately reconstruct the original video. * CCIR 601 (

) * H.261 (

) *

H.263 H.263 is a video compression standard originally designed as a low-bit-rate compressed format for videotelephony. It was standardized by the ITU-T Video Coding Experts Group (VCEG) in a project ending in 1995/1996. It is a member of the H.26x fam ...

(

) * H.264/MPEG-4 AVC (

+ ISO) * H.265 * M-JPEG ( ISO) *

MPEG-1 MPEG-1 is a standard for lossy compression of video and audio. It is designed to compress VHS-quality raw digital video and CD audio down to about 1.5 Mbit/s (26:1 and 6:1 compression ratios respectively) without excessive quality loss, mak ...

( ISO) *

(

+ ISO) *

( ISO) * Ogg- Theora * VP8-

WebM WebM is an audiovisual media file format. It is primarily intended to offer a royalty-free alternative to use in the HTML5 video and the HTML5 audio elements. It has a sister project, WebP, for images. The development of the format is sponso ...

* VC-1 ( SMPTE)

References

External links

* *
Programmer's Guide to Video Systems: in-depth technical info on 480i, 576i, 1080i, 720p, etc.

Format Descriptions for Moving Images
{{Authority control Digital television Film and video technology High-definition television Display technology Television terminology History of television Media formats Articles containing video clips

History

Analog video

Digital video

Characteristics of video streams

Number of frames per second

Interlaced vs progressive

Aspect ratio

Color model and depth

Video quality

Video compression method (digital only)

Stereoscopic

Formats

Analog video

Digital video

Transport medium

Display standards

Digital television

Analog television

Computer displays

Recording

Digital encoding formats

See also

References

External links