Video

analog videovideo albumvideo recordingvideo signalvideo albumsvideo formatrecordingvideo analogvideo feed
Video is an electronic medium for the recording, copying, playback, broadcasting, and display of moving visual media.wikipedia
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Mechanical television

Televisormechanicalelectromechanical television
Video was first developed for mechanical television systems, which were quickly replaced by cathode ray tube (CRT) systems which were later replaced by flat panel displays of several types. Video technology was first developed for mechanical television systems, which were quickly replaced by cathode ray tube (CRT) television systems, but several new technologies for video display devices have since been invented.
Mechanical television or mechanical scan television is a television system that relies on a mechanical scanning device, such as a rotating disk with holes in it or a rotating mirror, to scan the scene and generate the video signal, and a similar mechanical device at the receiver to display the picture.

Flat-panel display

flat panel displayflat panelflat panel displays
Video was first developed for mechanical television systems, which were quickly replaced by cathode ray tube (CRT) systems which were later replaced by flat panel displays of several types.
A flat-panel display (FPD) is an electronic viewing technology used to enable people to see content (still images, moving images, text, or other visual material) in a range of entertainment, consumer electronics, personal computer, and mobile devices, and many types of medical, transportation and industrial equipment.

Cathode-ray tube

cathode ray tubeCRTcathode ray tubes
Video was first developed for mechanical television systems, which were quickly replaced by cathode ray tube (CRT) systems which were later replaced by flat panel displays of several types. Video technology was first developed for mechanical television systems, which were quickly replaced by cathode ray tube (CRT) television systems, but several new technologies for video display devices have since been invented.
In color devices, an image is produced by controlling the intensity of each of the three electron beams, one for each additive primary color (red, green, and blue) with a video signal as a reference.

Video tape recorder

VTRvideotape recordervideo tape recording
Charles Ginsburg led an Ampex research team developing one of the first practical video tape recorder (VTR).
A video tape recorder (VTR) is a tape recorder designed to record and playback video and audio material on magnetic tape.

Videotape

videocassettevideo tapevideo
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.
Videotape is magnetic tape used for storing video and usually sound in addition.

Videocassette recorder

VCRvideo cassette recorderVCRs
However, prices gradually dropped over the years; in 1971, Sony began selling videocassette recorder (VCR) decks and tapes into the consumer market.
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 recording.

Digital video

videodigitaldigitally
The use of digital techniques in video created digital video. Pixels 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.
Digital video is an electronic representation of moving visual images (video) in the form of encoded digital data.

Lossy compression

lossylossy data compressioncompressed
Practical digital video was made possible with discrete cosine transform (DCT) coding, a lossy compression process developed in the early 1970s.
Lossy compression is most commonly used to compress multimedia data (audio, video, and images), especially in applications such as streaming media and internet telephony.

Television

TVtelevisedtelevisions
Video technology was first developed for mechanical television systems, which were quickly replaced by cathode ray tube (CRT) television systems, but several new technologies for video display devices have since been invented.
In 1907, Russian scientist Boris Rosing used a CRT in the receiving end of an experimental video signal to form a picture.

Video quality

qualityfull reference metricmodels
Deinterlacing cannot, however, produce video quality that is equivalent to true progressive scan source material. Video quality can be measured with formal metrics like Peak signal-to-noise ratio (PSNR) or through subjective video quality assessment using expert observation.
Video quality is a characteristic of a video passed through a video transmission/processing system, a formal or informal measure of perceived video degradation (typically, compared to the original video).

Scan line

scanlinescan linesscanlines
In interlaced video, the horizontal scan lines 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.
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.

Broadcasting

broadcastbroadcasterbroadcasters
Video is an electronic medium for the recording, copying, playback, broadcasting, and display of moving visual media.

Rec. 601

CCIR 601BT.601ITU-R BT.601
Pixels 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.
601 or BT.601 (or its former name, CCIR 601''') is a standard originally issued in 1982 by the CCIR (an organization which has since been renamed as the International Telecommunication Union – Radiocommunication sector) for encoding interlaced analog video signals in digital video form.

Display device

displayvideo monitorbezel
Video technology was first developed for mechanical television systems, which were quickly replaced by cathode ray tube (CRT) television systems, but several new technologies for video display devices have since been invented.
2-dimensional displays that cover a full area (usually a rectangle) are also called video displays, since it is the main modality of presenting video.

Ampex

Ampex CorporationAmpex RecordsAmpex HS-100 model
Charles Ginsburg led an Ampex research team developing one of the first practical video tape recorder (VTR).
Starting in the early 1950s, RCA, Bing Crosby and others tried to record analog video on very fast-moving magnetic tape.

YCbCr

YC B C R Y′CbCrY'CbCr
There are several such representations in common use: YIQ is used in NTSC television, YUV is used in PAL television, YDbDr is used by SECAM television and YCbCr is used for digital video.
YCbCr, Y′CbCr, or Y Pb/Cb Pr/Cr, also written as YC B C R or Y'C B C R, is a family of color spaces used as a part of the color image pipeline in video and digital photography systems.

Line doubler

line doublingde-interlacingdisplaying each line of pixels twice
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 line doubler is a device used to deinterlace video signals prior to display.

NTSC

analogNTSC-M30p
PAL standards (Europe, Asia, Australia, etc.) and SECAM (France, Russia, parts of Africa etc.) specify 25 frame/s, while NTSC standards (USA, Canada, Japan, etc.) specify 29.97 frame/s.
NTSC color encoding is used with the System M television signal, which consists of 30⁄1.001 (approximately 29.97) interlaced frames of video per second.

Optical disc

optical mediaoptical data storageoptical discs
Analog and digital variants exist and can be carried on a variety of media, including radio broadcast, magnetic tape, optical discs, computer files, and network streaming.
The LaserDisc format stored analog video signals for the distribution of home video, but commercially lost to the VHS videocassette format, due mainly to its high cost and non-re-recordability; other first-generation disc formats were designed only to store digital data and were not initially capable of use as a digital video medium.

Subjective video quality

psycho-visual optimizationsratings obtained by human viewerssubjective quality assessment
Video quality can be measured with formal metrics like Peak signal-to-noise ratio (PSNR) or through subjective video quality assessment using expert observation.
It is concerned with how video is perceived by a viewer (also called "observer" or "subject") and designates their opinion on a particular video sequence and therefore related to the field of Quality of Experience.

Deinterlacing

deinterlacedeinterlacedDe-interlacing
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.
Both video and photographic film capture a series of frames (still images) in rapid succession; however, television systems read the captured image by serially scanning the image sensor by lines (rows).

Video coding format

video coding standardsvideo codingvideo coding standard
DCT coding was adapted into motion-compensated DCT video compression in the late 1980s, starting with H.261, the first practical digital video coding standard.
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).

Video clip

video clipsvideoclipclips
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.
Video clips are short clips of video, usually part of a longer recording.

Magnetic tape

tapetapesanalog tape
Analog and digital variants exist and can be carried on a variety of media, including radio broadcast, magnetic tape, optical discs, computer files, and network streaming.
Many saw the potential of making the same improvements in recording the video signals used by television.

Aspect ratio (image)

4:3aspect ratio16:9
Video systems vary in display resolution, aspect ratio, refresh rate, color capabilities and other qualities.
16:9 is gaining popularity as a format in all classes of consumer still cameras which also shoot High Definition (HD) video.