Video
Overview
 
Video is the technology of electronically
Electronics
Electronics is the branch of science, engineering and technology that deals with electrical circuits involving active electrical components such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive interconnection technologies...

 capturing
Videography
Videography refers to the process of capturing moving images on electronic media even streaming media). The term includes methods of video production and post-production...

, recording
Recording
Recording is the process of capturing data or translating information to a recording format stored on some storage medium, which is often referred to as a record or, if an auditory medium, a recording....

, processing, storing, transmitting, and reconstructing a sequence of still images representing scenes
Scene (film)
In TV and movies, a scene is generally thought of as the action in a single location and continuous time. Due to the ability to edit recorded visual works, it is typically much shorter than a stage play scene....

 in motion.
Video technology
Technology
Technology is the making, usage, and knowledge of tools, machines, techniques, crafts, systems or methods of organization in order to solve a problem or perform a specific function. It can also refer to the collection of such tools, machinery, and procedures. The word technology comes ;...

 was first developed for cathode ray tube
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...

 (CRT) television
Television
Television is a telecommunication medium for transmitting and receiving moving images that can be monochrome or colored, with accompanying sound...

 systems, but several new technologies for video display device
Display device
A display device is an output device for presentation of information in visual or tactile form...

s have since been invented. Charles Ginsburg
Charles Ginsburg
Charles Ginsburg was an engineer and the leader of a research team at Ampex which developed one of the first practical videotape recorders....

 led an Ampex
Ampex
Ampex is an American electronics company founded in 1944 by Alexander M. Poniatoff. The name AMPEX is an acronym, created by its founder, which stands for Alexander M. Poniatoff Excellence...

 research team developing the first practical video tape recorder
Video tape recorder
A video tape recorder is a tape recorder that can record video material, usually on a magnetic tape. VTRs originated as individual tape reels, serving as a replacement for motion picture film stock and making recording for television applications cheaper and quicker. An improved form included the...

 (VTR). In 1951 the first video tape recorder captured live images from television cameras by converting the camera's electrical impulses and saving the information onto magnetic video tape.

Video recorders sold for $50,000 in 1956, and videotape cost $300 per one-hour reel.
Encyclopedia
Video is the technology of electronically
Electronics
Electronics is the branch of science, engineering and technology that deals with electrical circuits involving active electrical components such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive interconnection technologies...

 capturing
Videography
Videography refers to the process of capturing moving images on electronic media even streaming media). The term includes methods of video production and post-production...

, recording
Recording
Recording is the process of capturing data or translating information to a recording format stored on some storage medium, which is often referred to as a record or, if an auditory medium, a recording....

, processing, storing, transmitting, and reconstructing a sequence of still images representing scenes
Scene (film)
In TV and movies, a scene is generally thought of as the action in a single location and continuous time. Due to the ability to edit recorded visual works, it is typically much shorter than a stage play scene....

 in motion.

History

Video technology
Technology
Technology is the making, usage, and knowledge of tools, machines, techniques, crafts, systems or methods of organization in order to solve a problem or perform a specific function. It can also refer to the collection of such tools, machinery, and procedures. The word technology comes ;...

 was first developed for cathode ray tube
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...

 (CRT) television
Television
Television is a telecommunication medium for transmitting and receiving moving images that can be monochrome or colored, with accompanying sound...

 systems, but several new technologies for video display device
Display device
A display device is an output device for presentation of information in visual or tactile form...

s have since been invented. Charles Ginsburg
Charles Ginsburg
Charles Ginsburg was an engineer and the leader of a research team at Ampex which developed one of the first practical videotape recorders....

 led an Ampex
Ampex
Ampex is an American electronics company founded in 1944 by Alexander M. Poniatoff. The name AMPEX is an acronym, created by its founder, which stands for Alexander M. Poniatoff Excellence...

 research team developing the first practical video tape recorder
Video tape recorder
A video tape recorder is a tape recorder that can record video material, usually on a magnetic tape. VTRs originated as individual tape reels, serving as a replacement for motion picture film stock and making recording for television applications cheaper and quicker. An improved form included the...

 (VTR). In 1951 the first video tape recorder captured live images from television cameras by converting the camera's electrical impulses and saving the information onto magnetic video tape.

Video recorders sold for $50,000 in 1956, and videotape cost $300 per one-hour reel. However, prices steadily dropped over the years; in 1971, Sony began selling videocassette recorder
Videocassette recorder
The videocassette recorder , is a type of electro-mechanical device that uses removable videocassettes that contain magnetic tape for recording analog audio and analog video from broadcast television so that the images and sound can be played back at a more convenient time...

 (VCR) tapes to the public. After the invention of the DVD
DVD
A DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than Compact Discs while having the same dimensions....

 in 1997 and Blu-ray Disc
Blu-ray Disc
Blu-ray Disc is an optical disc storage medium designed to supersede the DVD format. The plastic disc is 120 mm in diameter and 1.2 mm thick, the same size as DVDs and CDs. Blu-ray Discs contain 25 GB per layer, with dual layer discs being the norm for feature-length video discs...

 in 2006, sales of videotape and tape equipment plummeted.

Later advances in computer technology allowed computers to capture, store, edit and transmit video clips.

Description of video

The term video (meaning "I see", from the Latin verb "videre") commonly refers to transmission and storage formats for moving pictures. Storage formats include digital video formats, including Blu-ray Disc
Blu-ray Disc
Blu-ray Disc is an optical disc storage medium designed to supersede the DVD format. The plastic disc is 120 mm in diameter and 1.2 mm thick, the same size as DVDs and CDs. Blu-ray Discs contain 25 GB per layer, with dual layer discs being the norm for feature-length video discs...

, DVD
DVD
A DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than Compact Discs while having the same dimensions....

, QuickTime
QuickTime
QuickTime is an extensible proprietary multimedia framework developed by Apple Inc., capable of handling various formats of digital video, picture, sound, panoramic images, and interactivity. The classic version of QuickTime is available for Windows XP and later, as well as Mac OS X Leopard and...

 (QT), and 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...

; and analog videotape
Videotape
A videotape is a recording of images and sounds on to magnetic tape as opposed to film stock or random access digital media. Videotapes are also used for storing scientific or medical data, such as the data produced by an electrocardiogram...

s, including VHS
VHS
The Video Home System is a consumer-level analog recording videocassette standard developed by Victor Company of Japan ....

 and Betamax
Betamax
Betamax was a consumer-level analog videocassette magnetic tape recording format developed by Sony, released on May 10, 1975. The cassettes contain -wide videotape in a design similar to the earlier, professional wide, U-matic format...

. Video can be recorded and transmitted in various physical media: in magnetic tape when recorded as PAL
PAL
PAL, short for Phase Alternating Line, is an analogue television colour encoding system used in broadcast television systems in many countries. Other common analogue television systems are NTSC and SECAM. This page primarily discusses the PAL colour encoding system...

 or NTSC
NTSC
NTSC, named for the National Television System Committee, is the analog television system that is used in most of North America, most of South America , Burma, South Korea, Taiwan, Japan, the Philippines, and some Pacific island nations and territories .Most countries using the NTSC standard, as...

 electric signals by video camera
Video camera
A video camera is a camera used for electronic motion picture acquisition, initially developed by the television industry but now common in other applications as well. The earliest video cameras were those of John Logie Baird, based on the electromechanical Nipkow disk and used by the BBC in...

s, or in 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...

 or DV
DV
DV is a format for the digital recording and playing back of digital video. The DV codec was launched in 1995 with joint efforts of leading producers of video camcorders....

 digital media when recorded by digital cameras.
Quality of video
Video quality
Video quality is a characteristic of a video passed through a video transmission/processing system, a formal or informal measure of perceived video degradation...

 essentially depends on the capturing method and storage used. Digital television
Digital television
Digital television is the transmission of audio and video by digital signals, in contrast to the analog signals used by analog TV...

 (DTV) is a relatively recent format with higher quality than earlier television formats and has become a standard for television video. (See List of digital television deployments by country.)

3D-video, digital video in three dimensions
3-D film
A 3-D film or S3D film is a motion picture that enhances the illusion of depth perception...

, premiered at the end of 20th century. Six or eight cameras with realtime depth measurement are typically used to capture 3D-video streams. The format of 3D-video is fixed in 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...

 Part 16 Animation Framework eXtension (AFX).

In many countries, the term video is often used informally to refer to both Videocassette recorder
Videocassette recorder
The videocassette recorder , is a type of electro-mechanical device that uses removable videocassettes that contain magnetic tape for recording analog audio and analog video from broadcast television so that the images and sound can be played back at a more convenient time...

s and video cassettes
Videotape
A videotape is a recording of images and sounds on to magnetic tape as opposed to film stock or random access digital media. Videotapes are also used for storing scientific or medical data, such as the data produced by an electrocardiogram...

; the meaning is normally clear from the context.

Number of frames per second

Frame rate
Frame rate
Frame rate is the frequency at which an imaging device produces unique consecutive images called frames. The term applies equally well to computer graphics, video cameras, film cameras, and motion capture systems...

, 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
PAL
PAL, short for Phase Alternating Line, is an analogue television colour encoding system used in broadcast television systems in many countries. Other common analogue television systems are NTSC and SECAM. This page primarily discusses the PAL colour encoding system...

 (Europe, Asia, Australia, etc.) and SECAM
SECAM
SECAM, also written SÉCAM , is an analog color television system first used in France....

 (France, Russia, parts of Africa etc.) standards specify 25 frame/s, while NTSC
NTSC
NTSC, named for the National Television System Committee, is the analog television system that is used in most of North America, most of South America , Burma, South Korea, Taiwan, Japan, the Philippines, and some Pacific island nations and territories .Most countries using the NTSC standard, as...

 (USA, Canada, Japan, etc.) specifies 29.97 frame/s. Film is shot at the slower frame rate of 24photograms/s, which complicates slightly the process of transferring a cinematic motion picture to video. The minimum frame rate to achieve the illusion of a moving image
Persistence of vision
Persistence of vision is the phenomenon of the eye by which an afterimage is thought to persist for approximately one twenty-fifth of a second on the retina....

 is about fifteen frames per second.

Interlacing

Video can be interlaced or progressive
Progressive scan
Progressive scanning is a way of displaying, storing, or transmitting moving images in which all the lines of each frame are drawn in sequence...

. Interlacing was invented as a way to reduce flicker in early mechanical
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...

 and 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...

 video displays without increasing the number of complete frames per second, which would have required sacrificing image detail in order to remain within the limitations of a narrow bandwidth. The horizontal scan line
Scan line
A scan line or scanline is one line, or row, in a raster scanning pattern, such as a line of video on a cathode ray tube display of a television set or computer monitor....

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 in the same way, 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 life-like reproduction (although with halved detail) of rapidly moving parts of the image when viewed on an interlaced CRT display, but the display of such a signal on a progressive scan device is problematic.

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 specified as 576i50, where 576 indicates the total number of horizontal scan lines, i indicates interlacing, and 50 indicates 50 fields (half-frames) per second.

In progressive scan systems, each refresh period updates all of the scan lines of 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. When displaying a natively interlaced signal, however, overall spatial resolution will be degraded by simple line doubling and artifacts such as flickering or "comb" effects in moving parts of the image will be seen unless special signal processing is applied to eliminate them. A procedure known as deinterlacing
Deinterlacing
Deinterlacing is the process of converting interlaced video, such as common analog television signals or 1080i format HDTV signals, into a non-interlaced form....

 can be used to 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
Video quality
Video quality is a characteristic of a video passed through a video transmission/processing system, a formal or informal measure of perceived video degradation...

 that is equivalent to true progressive scan source material.

Display resolution

The size of a video image is measured in pixel
Pixel
In digital imaging, a pixel, or pel, is a single point in a raster image, or the smallest addressable screen element in a display device; it is the smallest unit of picture that can be represented or controlled....

s for digital video, or horizontal scan lines and vertical lines of resolution for analog video. In the digital domain (e.g. DVD) standard-definition television (SDTV
Standard-definition television
Sorete-definition television is a television system that uses a resolution that is not considered to be either enhanced-definition television or high-definition television . The term is usually used in reference to digital television, in particular when broadcasting at the same resolution as...

) is specified as 720/704/640×480i60 for NTSC and 768/720×576i50 for PAL or SECAM resolution. However in the analog domain, the number of visible scanlines remains constant (486 NTSC/576 PAL) while the horizontal measurement varies with the quality of the signal: approximately 320 pixels per scanline for VCR quality, 400 pixels for TV broadcasts, and 720 pixels for DVD sources. Aspect ratio is preserved because of non-square "pixels".

New high-definition televisions (HDTV
High-definition television
High-definition television is video that has resolution substantially higher than that of traditional television systems . HDTV has one or two million pixels per frame, roughly five times that of SD...

) are capable of resolutions up to 1920×1080p60, i.e. 1920 pixels per scan line by 1080 scan lines, progressive, at 60 frames per second.

Video resolution for 3D-video is measured in voxel
Voxel
A voxel is a volume element, representing a value on a regular grid in three dimensional space. This is analogous to a pixel, which represents 2D image data in a bitmap...

s (volume picture element, representing a value in three dimensional space). For example 512×512×512 voxels resolution, now used for simple 3D-video, can be displayed even on some PDA
Personal digital assistant
A personal digital assistant , also known as a palmtop computer, or personal data assistant, is a mobile device that functions as a personal information manager. Current PDAs often have the ability to connect to the Internet...

s.

Aspect ratio

Aspect ratio
Aspect ratio (image)
The aspect ratio of an image is the ratio of the width of the image to its height, expressed as two numbers separated by a colon. That is, for an x:y aspect ratio, no matter how big or small the image is, if the width is divided into x units of equal length and the height is measured using this...

 describes the dimensions of video screens and video picture elements. All popular video formats are rectilinear, and so can be described by a ratio between width and height. The screen aspect ratio of 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
Academy ratio
The Academy ratio of 1.375:1 is an aspect ratio of a frame of 35mm film when used with 4-perf pulldown. It was standardized by the Academy of Motion Picture Arts and Sciences as the standard film aspect ratio in 1932, although similar-sized ratios were used as early as 1928.The Academy ratio is...

) is 1.375:1.

Ratios where the height is taller than the width are uncommon in general everyday use, but do have application in computer systems where the screen may be better suited for a vertical layout. The most common tall aspect ratio of 3:4 is referred to as portrait mode and is created by physically rotating the display device 90 degrees from the normal position. Other tall aspect ratios such as 9:16 are technically possible but rarely used. (For a more detailed discussion of this topic please refer to the page orientation
Page orientation
Page orientation is the way in which a rectangular page is oriented for normal viewing. The two most common types of orientation are portrait and landscape...

 article.)

Pixels on computer monitors are usually square, but pixels used in digital video
Digital video
Digital video is a type of digital recording system that works by using a digital rather than an analog video signal.The terms camera, video camera, and camcorder are used interchangeably in this article.- History :...

 often have non-square aspect ratios, such as those used in the PAL and NTSC variants of the CCIR 601
CCIR 601
ITU-R Recommendation BT.601, more commonly known by the abbreviations Rec. 601 or BT.601 is a standard published in 1982 by International Telecommunication Union - Radiocommunications sector for encoding interlaced analog video signals in digital video form...

 digital video standard, and the corresponding anamorphic widescreen formats. Therefore, an NTSC DV image which is 720 pixels by 480 pixels is displayed with the aspect ratio of 4:3 (which is the traditional television standard) if the pixels are thin and displayed with the aspect ratio of 16:9 (which is the anamorphic widescreen format) if the pixels are fat.

Color space and bits per pixel

Color model name describes the video color representation. YIQ
YIQ
YIQ is the color space used by the NTSC color TV system, employed mainly in North and Central America, and Japan. It is currently in use only for low-power television stations, as full-power analog transmission was ended by the U.S. Federal Communications Commission on 12 June 2009...

was used in NTSC television. It corresponds closely to the YUV
YUV
YUV is a color space typically used as part of a color image pipeline. It encodes a color image or video taking human perception into account, allowing reduced bandwidth for chrominance components, thereby typically enabling transmission errors or compression artifacts to be more efficiently...

scheme used in NTSC and PAL television and the YDbDr
YDbDr
YDbDr, sometimes written YDBDR, is the colour space used in the SÉCAM analog terrestrial colour television broadcasting standard, which is used in France and some countries of the former Eastern Bloc. It is very close to YUV and its related colour spaces such as YIQ , YPbPr and YCbCr.YDbDr is...

scheme used by SECAM television.

The number of distinct colors that can be represented by a pixel depends on the number of bits per pixel (bpp). A common way to reduce the number of bits per pixel in digital video is by chroma subsampling
Chroma subsampling
Chroma subsampling is the practice of encoding images by implementing less resolution for chroma information than for luma information, taking advantage of the human visual system's lower acuity for color differences than for luminance....

 (e.g. 4:4:4, 4:2:2, 4:2:0/4:1:1).

Video quality

Video quality
Video quality
Video quality is a characteristic of a video passed through a video transmission/processing system, a formal or informal measure of perceived video degradation...

 can be measured with formal metrics like PSNR
Peak signal-to-noise ratio
The phrase peak signal-to-noise ratio, often abbreviated PSNR, is an engineering term for the ratio between the maximum possible power of a signal and the power of corrupting noise that affects the fidelity of its representation...

 or with subjective video quality
Subjective video quality
Subjective video quality is a subjective characteristic of video quality. It is concerned with how video is perceived by a viewer and designates his or her opinion on a particular video sequence...

 using expert observation.

The subjective video quality of a video processing system may be evaluated as follows:
  • Choose the video sequences (the SRC) to use for testing.
  • Choose the settings of the system to evaluate (the HRC).
  • Choose a test method
    Scientific method
    Scientific method refers to a body of techniques for investigating phenomena, acquiring new knowledge, or correcting and integrating previous knowledge. To be termed scientific, a method of inquiry must be based on gathering empirical and measurable evidence subject to specific principles of...

     for how to present video sequences to experts and to collect their ratings.
  • Invite a sufficient number of experts, preferably not fewer than 15.
  • Carry out testing.
  • Calculate the average marks for each HRC based on the experts' ratings.


Many subjective video quality
Subjective video quality
Subjective video quality is a subjective characteristic of video quality. It is concerned with how video is perceived by a viewer and designates his or her opinion on a particular video sequence...

 methods are described in the 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 BT.500. One of the standardized method 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)

A wide variety of methods are used to compress video streams. Video data contains spatial and temporal redundancy
Redundancy (information theory)
Redundancy in information theory is the number of bits used to transmit a message minus the number of bits of actual information in the message. Informally, it is the amount of wasted "space" used to transmit certain data...

, making uncompressed video streams extremely inefficient. 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
Image compression
The objective of image compression is to reduce irrelevance and redundancy of the image data in order to be able to store or transmit data in an efficient form.- Lossy and lossless compression :...

. Likewise, temporal redundancy can be reduced by registering differences between frames; this task is known as interframe compression, including motion compensation
Motion compensation
Motion compensation is an algorithmic technique employed in the encoding of video data for video compression, for example in the generation of MPEG-2 files. Motion compensation describes a picture in terms of the transformation of a reference picture to the current picture. The reference picture...

 and other techniques. The most common modern standards are MPEG-2
MPEG-2
MPEG-2 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 which permit storage and transmission of movies using currently available storage media and transmission...

, used for DVD
DVD
A DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than Compact Discs while having the same dimensions....

, Blu-ray
Blu-ray Disc
Blu-ray Disc is an optical disc storage medium designed to supersede the DVD format. The plastic disc is 120 mm in diameter and 1.2 mm thick, the same size as DVDs and CDs. Blu-ray Discs contain 25 GB per layer, with dual layer discs being the norm for feature-length video discs...

 and satellite television
Satellite television
Satellite television is television programming delivered by the means of communications satellite and received by an outdoor antenna, usually a parabolic mirror generally referred to as a satellite dish, and as far as household usage is concerned, a satellite receiver either in the form of an...

, and 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...

, used for AVCHD
AVCHD
AVCHD is a file-based format for the digital recording and playback of high-definition video....

, Mobile phones (3GP) and Internet.

Bit rate (digital only)

Bit rate
Bit rate
In telecommunications and computing, bit rate is the number of bits that are conveyed or processed per unit of time....

is a measure of the rate of information content in a video stream. It is quantified using the bit per second (bit/s or bps) unit or Megabits per second (Mbit/s). A higher bit rate allows better video quality
Video quality
Video quality is a characteristic of a video passed through a video transmission/processing system, a formal or informal measure of perceived video degradation...

. For example VideoCD, with a bit rate of about 1 Mbit/s, is lower quality than DVD, with maximum bit rate of 10.08 Mbit/s for video. HD (High Definition Digital Video and TV) has a still higher quality, with a bit rate of about 20 Mbit/s.

Variable bit rate (VBR) is a strategy to maximize the visual video quality and minimize the bit rate. On fast motion scenes, a variable bit rate uses more bits than it does on slow motion scenes of similar duration yet achieves a consistent visual quality. For real-time and non-buffered video streaming when the available bandwidth is fixed, e.g. in videoconferencing delivered on channels of fixed bandwidth, a constant bit rate (CBR) must be used.

Stereoscopic

Stereoscopic video can be created 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.
  • one channel with two overlaid 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/right frames for each eye, using LCD shutter glasses
    LCD shutter glasses
    Liquid crystal shutter glasses are glasses used in conjunction with a display screen to create the illusion of a three dimensional image, an example of stereoscopy. Each eye's glass contains a liquid crystal layer which has the property of becoming dark when voltage is applied, being otherwise...

     which read the frame sync from the VGA Display Data Channel
    Display Data Channel
    The Display Data Channel or DDC is a collection of digital communication protocols between a computer display and a graphics adapter that enables the display to communicate its supported display modes to the adapter and to enable the computer host to adjust monitor parameters, such as brightness...

     to alternately cover each eye, so the appropriate eye sees the correct frame. This method is most common in computer virtual reality
    Virtual reality
    Virtual reality , also known as virtuality, is a term that applies to computer-simulated environments that can simulate physical presence in places in the real world, as well as in imaginary worlds...

     applications such as in a Cave Automatic Virtual Environment
    Cave Automatic Virtual Environment
    A Cave Automatic Virtual Environment is an immersive virtual reality environment where projectors are directed to three, four, five or six of the walls of a room-sized cube...

    , but reduces the effective video framerate to one-half of normal (for example, from 120 Hz to 60 Hz).


Blu-ray Disc
Blu-ray Disc
Blu-ray Disc is an optical disc storage medium designed to supersede the DVD format. The plastic disc is 120 mm in diameter and 1.2 mm thick, the same size as DVDs and CDs. Blu-ray Discs contain 25 GB per layer, with dual layer discs being the norm for feature-length video discs...

s greatly improve the sharpness and detail of the two-color 3D effect in color coded stereo programs. See articles Stereoscopy
Stereoscopy
Stereoscopy refers to a technique for creating or enhancing the illusion of depth in an image by presenting two offset images separately to the left and right eye of the viewer. Both of these 2-D offset images are then combined in the brain to give the perception of 3-D depth...

 and 3-D film
3-D film
A 3-D film or S3D film is a motion picture that enhances the illusion of depth perception...

.

Video formats

There are different layers of video transmission and storage, each with its own set of formats to choose from.

For transmission, there is a physical connector and signal protocol ("video connection standard" below). A given physical link can carry certain "display standards" which specify a particular refresh rate, display resolution
Display resolution
The display resolution of a digital television 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 is controlled by all different factors in cathode ray tube , flat panel or projection...

, and color space
Color space
A color model is an abstract mathematical model describing the way colors can be represented as tuples of numbers, typically as three or four values or color components...

.

Many analog and digital recording formats are in use, and digital video clips can also be stored on a computer file system as file
Computer file
A computer file is a block of arbitrary information, or resource for storing information, which is available to a computer program and is usually based on some kind of durable storage. A file is durable in the sense that it remains available for programs to use after the current program has finished...

s which have their own formats. In addition to the physical format used by the data storage device
Data storage device
thumb|200px|right|A reel-to-reel tape recorder .The magnetic tape is a data storage medium. The recorder is data storage equipment using a portable medium to store the data....

 or transmission medium, the stream of ones and zeros that is sent must be in a particular digital "video encoding", of which a number are available.

Video connectors, cables, and signal standards


Digital television

New formats for digital television
Digital television
Digital television is the transmission of audio and video by digital signals, in contrast to the analog signals used by analog TV...

 broadcasts use the MPEG-2
MPEG-2
MPEG-2 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 which permit storage and transmission of movies using currently available storage media and transmission...

 video codec
Video codec
A video codec is a device or software that enables video compression and/or decompression for digital video. The compression usually employs lossy data compression. Historically, video was stored as an analog signal on magnetic tape...

 and include:
  • ATSC - USA, 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...

    , Korea
    Korea
    Korea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the...

  • Digital Video Broadcasting (DVB) - Europe
    Europe
    Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

  • ISDB
    ISDB
    Integrated Services Digital Broadcasting is a Japanese standard for digital television and digital radio used by the country's radio and television stations. ISDB replaced the previously used MUSE "Hi-vision" analogue HDTV system...

     - Japan
    Japan
    Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

    • ISDB-Tb
      ISDB-Tb
      ISDB-Tb is the short for International System for Digital Broadcast, Terrestrial, Brazilian version.It is a Digital TV system based on Japanese ISDB-T . ISDB-Tb system is also known as SBTVD and is used in Brazil...

       - Uses the MPEG-4 video codec. Brazil
      Brazil
      Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

      , Argentina
      Argentina
      Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

  • Digital Multimedia Broadcasting
    Digital Multimedia Broadcasting
    Digital Multimedia Broadcasting is a digital radio transmission technology developed in South Korea as part of the national IT project for sending multimedia such as TV, radio and datacasting to mobile devices such as mobile phones...

     (DMB) - Korea
    Korea
    Korea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the...


Analog television

Analog television
Analog television
Analog television is the analog transmission that involves the broadcasting of encoded analog audio and analog video signal: one in which the message conveyed by the broadcast signal is a function of deliberate variations in the amplitude and/or frequency of the signal...

 broadcast standards include:
  • FCS
    Field-sequential color system
    A field-sequential color system is a color television system in which the primary color information is transmitted in successive images, and which relies on the human vision system to fuse the successive images into a color picture. One field-sequential system was developed by Dr. Peter Goldmark...

     - USA, Russia; obsolete
  • MAC
    Multiplexed Analogue Components
    Multiplexed Analogue Components was a satellite television transmission standard, originally proposed for use on a Europe-wide terrestrial HDTV system, although it was never used terrestrially.- Technical overview :...

     - Europe; obsolete
  • MUSE
    Multiple sub-nyquist sampling Encoding system
    MUSE , was a dot-interlaced digital video compression system that used analog modulation for transmission to deliver 1125-line high definition video signals to the home. Japan had the earliest working HDTV system, which was named Hi-Vision with design efforts going back to 1979...

     - Japan
  • NTSC
    NTSC
    NTSC, named for the National Television System Committee, is the analog television system that is used in most of North America, most of South America , Burma, South Korea, Taiwan, Japan, the Philippines, and some Pacific island nations and territories .Most countries using the NTSC standard, as...

     - USA
    United States
    The United States of America is a federal constitutional republic comprising fifty states and a federal district...

    , 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...

    , Japan
    Japan
    Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

  • PAL
    PAL
    PAL, short for Phase Alternating Line, is an analogue television colour encoding system used in broadcast television systems in many countries. Other common analogue television systems are NTSC and SECAM. This page primarily discusses the PAL colour encoding system...

      - Europe
    Europe
    Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

    , Asia
    Asia
    Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...

    , Oceania
    Oceania
    Oceania is a region centered on the islands of the tropical Pacific Ocean. Conceptions of what constitutes Oceania range from the coral atolls and volcanic islands of the South Pacific to the entire insular region between Asia and the Americas, including Australasia and the Malay Archipelago...

    • PAL-M - PAL variation. Brazil
      Brazil
      Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

      , Argentina
      Argentina
      Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

    • PALplus
      PALplus
      PALplus is an extension of the PAL analogue broadcasting system for transmitting 16:9 programs without sacrificing vertical resolution. It followed experiences with the HD-MAC and D2-MAC, standards that were incompatible with existing receivers but featured a 16:9 aspect ratio...

       - PAL extension, Europe
      Europe
      Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

  • RS-343 (military)
  • SECAM
    SECAM
    SECAM, also written SÉCAM , is an analog color television system first used in France....

     - 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...

    , Former Soviet Union
    Soviet Union
    The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

    , Central Africa
    Central Africa
    Central Africa is a core region of the African continent which includes Burundi, the Central African Republic, Chad, the Democratic Republic of the Congo, and Rwanda....



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 synchronization information or a time delay. This surrounding margin is known as a blanking interval or blanking region; the horizontal and vertical front porch
Front Porch
Front Porch, Inc. provides services to Internet Service Providers. Front Porch technology enables an Internet Service Provider to insert its own messages to be presented to users as they use their web browsers, such as customer service notices or online advertising...

 and back porch are the building blocks of the blanking interval.

Many countries are planning a digital switchover soon.

Computer displays

See Computer display standard
Computer display standard
Computer display standards are often a combination of aspect ratio, display resolution, color depth, and refresh rate.This article describes the different display standards for computer displays.-History:...

 for a list of standards used for computer monitors and comparison with those used for television.

Analog tape formats

  • 1" Type B video tape
    1 inch type B videotape
    1 inch type B VTR is a reel-to-reel analog recording video tape format developed by the Bosch Fernseh division of Bosch in Germany in 1976...

     (Robert Bosch GmbH
    Robert Bosch GmbH
    Robert Bosch GmbH is a multinational engineering and electronics company headquartered in Gerlingen, near Stuttgart, Germany. It is the world's largest supplier of automotive components...

    )
  • 1" Type C videotape (Ampex
    Ampex
    Ampex is an American electronics company founded in 1944 by Alexander M. Poniatoff. The name AMPEX is an acronym, created by its founder, which stands for Alexander M. Poniatoff Excellence...

    , Marconi
    Marconi
    -People:*Guglielmo Marconi, Italian-born radio pioneer*David Marconi, American screenwriter*Dominic Anthony Marconi, American Roman Catholic bishop*Enrico Marconi, also known as Henryk Marconi, architect*Gloria Marconi, Italian long-distance runner...

     and Sony
    Sony
    , commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....

    )
  • 2" Quadruplex videotape (Ampex
    Ampex
    Ampex is an American electronics company founded in 1944 by Alexander M. Poniatoff. The name AMPEX is an acronym, created by its founder, which stands for Alexander M. Poniatoff Excellence...

    )
  • 2" Helical Scan Videotape (Rank Cintel)
  • Betacam
    Betacam
    Betacam is family of half-inch professional videocassette products developed by Sony in 1982. In colloquial use, "Betacam" singly is often used to refer to a Betacam camcorder, a Betacam tape, a Betacam video recorder or the format itself....

     (Sony)
  • Betacam SP (Sony)
  • Betamax
    Betamax
    Betamax was a consumer-level analog videocassette magnetic tape recording format developed by Sony, released on May 10, 1975. The cassettes contain -wide videotape in a design similar to the earlier, professional wide, U-matic format...

     (Sony)
  • S-VHS
    S-VHS
    S-VHS is an improved version of the VHS standard for consumer-level analog recording videocassettes. It was introduced by JVC in Japan in April 1987 with the HR-S7000 VCR and certain overseas markets soon afterwards...

     (JVC
    JVC
    , usually referred to as JVC, is a Japanese international consumer and professional electronics corporation based in Yokohama, Japan which was founded in 1927...

    ) (1987)
  • W-VHS
    W-VHS
    W-VHS is a HDTV analog recording videocassette format created by JVC. The format was originally introduced in 1994 for use with Japan's Hi-Vision, an early analog high-definition television system named MUSE....

     (JVC
    JVC
    , usually referred to as JVC, is a Japanese international consumer and professional electronics corporation based in Yokohama, Japan which was founded in 1927...

    ) (1994)
  • U-matic
    U-matic
    U-matic is an analog recording videocassette format first shown by Sony in prototype in October 1969, and introduced to the market in September 1971. It was among the first video formats to contain the videotape inside a cassette, as opposed to the various Reel-to-Reel or open-reel formats of the...

     3/4" (Sony
    Sony
    , commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....

    )
  • VCR, VCR-LP, SVR
    Video Cassette Recording
    Video Cassette Recording was an early domestic analog recording format designed by Philips. It was the first successful consumer-level home videocassette recorder system. Later variants included the VCR-LP and Super Video formats.The VCR format was introduced in 1972, just after the Sony...

  • VERA
    VERA videotape format
    Vision electronic recording apparatus was an early analog recording videotape format developed from 1952 by the BBC under project manager Dr Peter Axon....

     (BBC
    BBC
    The British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...

     experimental format ca. 1958)
  • VHS
    VHS
    The Video Home System is a consumer-level analog recording videocassette standard developed by Victor Company of Japan ....

     (JVC
    JVC
    , usually referred to as JVC, is a Japanese international consumer and professional electronics corporation based in Yokohama, Japan which was founded in 1927...

    )
  • VHS-C
    VHS-C
    VHS-C is the compact VHS videocassette format introduced in 1982 and used primarily for consumer-grade compact analog recording camcorders. The format is based on the same video tape as is used in VHS, and can be played back in a standard VHS VCR with an adapter...

     (JVC
    JVC
    , usually referred to as JVC, is a Japanese international consumer and professional electronics corporation based in Yokohama, Japan which was founded in 1927...

    )
  • Video 2000
    Video 2000
    Video 2000 was a consumer videocassette recorder system and analog recording videocassette standard developed by Philips and Grundig to compete with JVC's VHS and Sony's Betamax video technologies...

     (Philips
    Philips
    Koninklijke Philips Electronics N.V. , more commonly known as Philips, is a multinational Dutch electronics company....

    )


(See List of video recording formats.)

Digital tape formats

  • Betacam IMX (Sony
    Sony
    , commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....

    )
  • D-VHS
    D-VHS
    D-VHS is a digital recording format developed by JVC, in collaboration with Hitachi, Matsushita, and Philips. The "D" in D-VHS originally stood for Data VHS, but with the expansion of the format from standard definition to high definition capability, JVC renamed it Digital VHS and uses that...

     (JVC
    JVC
    , usually referred to as JVC, is a Japanese international consumer and professional electronics corporation based in Yokohama, Japan which was founded in 1927...

    )
  • D-Theater
  • D1
    D1 (Sony)
    D-1 is an SMPTE digital recording video standard, introduced in 1986 through efforts by SMPTE engineering committees. It started as a Sony and Bosch - BTS product and was the first major professional digital video format.- Format :...

     (Sony
    Sony
    , commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....

    )
  • D2
    D2 (video format)
    D-2 is a professional digital recording videocassette format created by Ampex and other manufacturers through a standards group of the Society of Motion Picture and Television Engineers and introduced at the 1988 NAB convention as a lower-cost alternative to the D-1 format...

     (Sony
    Sony
    , commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....

    )
  • D3
  • D5 HD
    D5 HD
    D-5 is a professional digital video format introduced by Panasonic in 1994. Like Sony's D-1 , it is an uncompressed digital component system , but uses the same half-inch tapes as Panasonic's digital composite D-3 format...

  • Digital-S
    Digital-S
    D-9 or Digital S as it was originally known, is a professional digital video videocassette format created by JVC in 1995. It is a direct competitor to Digital Betacam. Its name was changed to D-9 in 1999 by the SMPTE...

     D9 (JVC
    JVC
    , usually referred to as JVC, is a Japanese international consumer and professional electronics corporation based in Yokohama, Japan which was founded in 1927...

    )
  • Digital Betacam (Sony
    Sony
    , commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....

    )
  • Digital8
    Digital8
    Digital8 is a consumer digital recording videocassette for camcorders based on the 8 mm video format developed by Sony, and introduced in 1999.The Digital8 format is a combination of the older Hi8 tape transport with the DV codec...

     (Sony
    Sony
    , commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....

    )
  • DV
    DV
    DV is a format for the digital recording and playing back of digital video. The DV codec was launched in 1995 with joint efforts of leading producers of video camcorders....

  • HDV
    HDV
    HDV is a format for recording of high-definition video on DV cassette tape. The format was originally developed by JVC and supported by Sony, Canon and Sharp...

  • ProHD
    ProHD
    ProHD is a name used by JVC for its MPEG-2-based professional camcorders. ProHD is not a video recording format, but rather "an approach for delivering affordable HD products" and a common name for "bandwidth efficient professional HD models"....

     (JVC
    JVC
    , usually referred to as JVC, is a Japanese international consumer and professional electronics corporation based in Yokohama, Japan which was founded in 1927...

    )
  • MicroMV
    MicroMV
    MicroMV was a proprietary videotape format introduced in 2001 by Sony. This cassette is physically smaller than a Digital8 or DV cassette. In fact, MicroMV is the smallest videotape format — 70% smaller than MiniDV or about the size of two US quarter coins. Each cassette can hold up to 60 minutes...

  • MiniDV

Optical disc storage formats

  • Blu-ray Disc
    Blu-ray Disc
    Blu-ray Disc is an optical disc storage medium designed to supersede the DVD format. The plastic disc is 120 mm in diameter and 1.2 mm thick, the same size as DVDs and CDs. Blu-ray Discs contain 25 GB per layer, with dual layer discs being the norm for feature-length video discs...

     (Sony
    Sony
    , commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....

    )
  • China Blue High-definition Disc (CBHD)
  • DVD
    DVD
    A DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than Compact Discs while having the same dimensions....

     (was Super Density Disc, DVD Forum
    DVD Forum
    The DVD Forum is an international organization composed of hardware, software, media and content companies that use and develop the DVD and formerly HD DVD formats...

    )
  • Professional Disc
  • Universal Media Disc
    Universal Media Disc
    The Universal Media Disc is an optical disc medium developed by Sony for use on their PlayStation Portable handheld gaming and multimedia platform...

     (UMD) (Sony
    Sony
    , commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....

    )

Discontinued

  • Enhanced Versatile Disc
    Enhanced Versatile Disc
    The Enhanced Versatile Disc is an optical medium-based digital audio/video format, developed to provide a means for playing HDTV content using existing optical media. It was announced on November 18, 2003, by the People's Republic of China's Xinhua News Agency as a response to the popular...

     (EVD, Chinese government-sponsored)
  • HD DVD
    HD DVD
    HD DVD is a discontinued high-density optical disc format for storing data and high-definition video.Supported principally by Toshiba, HD DVD was envisioned to be the successor to the standard DVD format...

     (NEC and Toshiba
    Toshiba
    is a multinational electronics and electrical equipment corporation headquartered in Tokyo, Japan. It is a diversified manufacturer and marketer of electrical products, spanning information & communications equipment and systems, Internet-based solutions and services, electronic components and...

    )
  • HD-VMD
  • Laserdisc
    Laserdisc
    LaserDisc was a home video format and the first commercial optical disc storage medium. Initially licensed, sold, and marketed as MCA DiscoVision in North America in 1978, the technology was previously referred to interally as Optical Videodisc System, Reflective Optical Videodisc, Laser Optical...

     (old, MCA
    Music Corporation of America
    MCA, Inc. was an American talent agency. Initially starting in the music business, they would next become a dominant force in the film business, and later expanded into the television business...

     and Philips
    Philips
    Koninklijke Philips Electronics N.V. , more commonly known as Philips, is a multinational Dutch electronics company....

    )

Digital encoding formats

  • CCIR 601
    CCIR 601
    ITU-R Recommendation BT.601, more commonly known by the abbreviations Rec. 601 or BT.601 is a standard published in 1982 by International Telecommunication Union - Radiocommunications sector for encoding interlaced analog video signals in digital video form...

     (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....

    )
  • H.261
    H.261
    H.261 is a ITU-T video coding standard, ratified in November 1988. It is the first member of the H.26x family of video coding standards in the domain of the ITU-T Video Coding Experts Group , and was the first video codec that was useful in practical terms.H.261 was originally designed for...

     (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....

    )
  • H.263
    H.263
    H.263 is a video compression standard originally designed as a low-bitrate compressed format for videoconferencing. It was developed by the ITU-T Video Coding Experts Group in a project ending in 1995/1996 as one member of the H.26x family of video coding standards in the domain of the ITU-T.H.263...

     (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....

    )
  • H.264/MPEG-4 AVC
    H.264/MPEG-4 AVC
    H.264/MPEG-4 Part 10 or AVC is a standard for video compression, and is currently one of the most commonly used formats for the recording, compression, and distribution of high definition video...

     (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....

     + ISO
    International Organization for Standardization
    The International Organization for Standardization , widely known as ISO, is an international standard-setting body composed of representatives from various national standards organizations. Founded on February 23, 1947, the organization promulgates worldwide proprietary, industrial and commercial...

    )
  • M-JPEG
    MJPEG
    In multimedia, Motion JPEG is an informal name for a class of video formats where each video frame or interlaced field of a digital video sequence is separately compressed as a JPEG image...

     (ISO
    International Organization for Standardization
    The International Organization for Standardization , widely known as ISO, is an international standard-setting body composed of representatives from various national standards organizations. Founded on February 23, 1947, the organization promulgates worldwide proprietary, industrial and commercial...

    )
  • MPEG-1
    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 1.5 Mbit/s without excessive quality loss, making video CDs, digital cable/satellite TV and digital audio broadcasting possible.Today, MPEG-1 has become...

     (ISO
    International Organization for Standardization
    The International Organization for Standardization , widely known as ISO, is an international standard-setting body composed of representatives from various national standards organizations. Founded on February 23, 1947, the organization promulgates worldwide proprietary, industrial and commercial...

    )
  • MPEG-2
    MPEG-2
    MPEG-2 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 which permit storage and transmission of movies using currently available storage media and transmission...

     (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....

     + ISO
    International Organization for Standardization
    The International Organization for Standardization , widely known as ISO, is an international standard-setting body composed of representatives from various national standards organizations. Founded on February 23, 1947, the organization promulgates worldwide proprietary, industrial and commercial...

    )
  • 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...

     (ISO
    International Organization for Standardization
    The International Organization for Standardization , widely known as ISO, is an international standard-setting body composed of representatives from various national standards organizations. Founded on February 23, 1947, the organization promulgates worldwide proprietary, industrial and commercial...

    )
  • Ogg
    Ogg
    Ogg is a free, open container format maintained by the Xiph.Org Foundation. The creators of the Ogg format state that it is unrestricted by software patents and is designed to provide for efficient streaming and manipulation of high quality digital multimedia.The Ogg container format can multiplex...

    -Theora
    Theora
    Theora is a free lossy video compression format. It is developed by the Xiph.Org Foundation and distributed without licensing fees alongside their other free and open media projects, including the Vorbis audio format and the Ogg container....

  • VC-1
    VC-1
    VC-1 is the informal name of the SMPTE 421M video codec standard, which was initially developed as a proprietary video format by Microsoft before it was released as a formal SMPTE standard video format on April 3, 2006...

     (SMPTE)


Display devices

Display device
Display device
A display device is an output device for presentation of information in visual or tactile form...

s for showing videos are generally full-area (rather than segmented display), sometimes simply called video displays.

See also

  • General
    • Audio
    • List of video topics
    • Video clips
    • Video editing
      Video editing
      The term video editing can refer to:* Linear video editing, using video tape* Non-linear editing system , using computers with video editing software* Offline editing* Online editing...


  • Video format
    • Analog television
      Analog television
      Analog television is the analog transmission that involves the broadcasting of encoded analog audio and analog video signal: one in which the message conveyed by the broadcast signal is a function of deliberate variations in the amplitude and/or frequency of the signal...

    • Cable television
      Cable television
      Cable television is a system of providing television programs to consumers via radio frequency signals transmitted to televisions through coaxial cables or digital light pulses through fixed optical fibers located on the subscriber's property, much like the over-the-air method used in traditional...

    • Color space
      Color space
      A color model is an abstract mathematical model describing the way colors can be represented as tuples of numbers, typically as three or four values or color components...

    • Digital television
      Digital television
      Digital television is the transmission of audio and video by digital signals, in contrast to the analog signals used by analog TV...

    • Digital video
      Digital video
      Digital video is a type of digital recording system that works by using a digital rather than an analog video signal.The terms camera, video camera, and camcorder are used interchangeably in this article.- History :...

    • Film formats
    • Interlaced
    • Progressive scan
      Progressive scan
      Progressive scanning is a way of displaying, storing, or transmitting moving images in which all the lines of each frame are drawn in sequence...

    • Satellite television
      Satellite television
      Satellite television is television programming delivered by the means of communications satellite and received by an outdoor antenna, usually a parabolic mirror generally referred to as a satellite dish, and as far as household usage is concerned, a satellite receiver either in the form of an...

    • Telecine
      Telecine
      Telecine is transferring motion picture film into video and is performed in a color suite. The term is also used to refer to the equipment used in the post-production process....

    • Television
      Television
      Television is a telecommunication medium for transmitting and receiving moving images that can be monochrome or colored, with accompanying sound...

    • Timecode
      Time code
      A timecode is a sequence of numeric codes generated at regular intervals by a timing system.- Video and film timecode :...

    • Video codec
      Video codec
      A video codec is a device or software that enables video compression and/or decompression for digital video. The compression usually employs lossy data compression. Historically, video was stored as an analog signal on magnetic tape...


  • Video usage
    • Closed-circuit television
      Closed-circuit television
      Closed-circuit television is the use of video cameras to transmit a signal to a specific place, on a limited set of monitors....

    • Fulldome video
      Fulldome
      Fulldome refers to immersive dome-based video projection environments. The dome, horizontal or tilted, is filled with real-time or pre-rendered computer animations, live capture images, or composited environments....

    • Optical feedback
      Optical feedback
      Optical feedback is the optical equivalent of acoustic feedback. A simple example is the feedback that occurs when a loop exists between an optical input, e.g., a video camera, and an optical output, e.g., a television screen or monitor...

    • Video art
      Video art
      Video art is a type of art which relies on moving pictures and comprises video and/or audio data. . Video art came into existence during the 1960s and 1970s, is still widely practiced and has given rise to the widespread use of video installations...

    • Interactive video
      Interactive video
      The term interactive video usually refers to a technique used to blend interaction and linear film or video.-Interactive video on broadband:Since 2005, interactive video has increased online as the result a number of factors including:...

    • Video production
      Video production
      Video production is videography, the process of capturing moving images on electronic media even streaming media. The term includes methods of production and post-production...

    • Video projector
      Video projector
      A video projector is an image projector that receives a video signal and projects the corresponding image on a projection screen using a lens system. All video projectors use a very bright light to project the image, and most modern ones can correct any curves, blurriness, and other...

    • Video synthesizer
      Video synthesizer
      A Video Synthesizer is a device that electronically creates a video signal.A video synthesizer is able to generate a variety of visual material without camera input through the use of internal video pattern generators, as seen in the stillframes of motion sequences shown above. It can also accept...

    • Video teleconference
    • Video communication
  • Video screen recording
    • Screencast
      Screencast
      A screencast is a digital recording of computer screen output, also known as a video screen capture, often containing audio narration. The term screencast compares with the related term screenshot; whereas screenshot is a picture of a computer screen, a screencast is essentially a movie of the...


  • Projects
    • Redesign project

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK