0:2:2 See: Dual Link
000/1001 The nominal 30 frames/60 fields per second of NTSC color television is usually multiplied by 1000/1001 (= 0.999) to produce slightly reduced rates of 29.97 and 59.94 Hz. This offset gives rise to niceties such as drop-frame timecode (dropping one frame per thousand - 33.3 seconds) and audio that also has to run at the right rate. Although having strictly analog origins from the very beginning of NTSC transmissions as a fix-it to avoid a clash of frequencies, it has also been extended into the digital and HD world where 24 Hz becomes 23.97 and 30 frames/60 fields per second are again changed to 29.97 and 59.94 Hz. Of course, as the frame/field frequency changes, so do the line and color subcarrier frequency as all are locked together. Note that this does not apply to PAL color systems as these always use the nominal values (25 Hz frame rate). See also: Drop-frame timecode, Embedded audio
10-bit lin A type of digital sampling of analog images that creates 10-bit (210, 1024 possible levels) numbers to describe the post gamma corrected analog brightness levels of an image. Lin, short for 'linear' means the levels are assigned equally to the levels of the post gamma corrected analog signal they describe. So an LSB change describes the same change in level if it is in a bright area or a dark area of the picture. Most professional HD and some SD television is sampled this way according to ITU-R BT.601 and 709. 10-bit lin sampling allows good quality to be maintained through TV production and post production where the processes can make particular demands outside the range of normal viewing, and so produce good results for viewers. However if color grading is required then the useful wide dynamic range that can be described by 10-bit log would be preferable. See also: 10-bit log, gamma
10-bit log This usually refers to a 10-bit sampling system that maps analog values logarithmically rather than linearly. It is widely used when scanning filmimages which are themselves a logarithmic representation of the film's exposure. This form of sampling is now available directly from some digital cinematography cameras. See also: 10-bit lin
13.5 MHz This is the sampling frequency of luminance in SD digital television. It is represented by the 4 in 4:2:2. The use of the number 4 is pure nostalgia as 13.5 MHz is in the region of 14.3 MHz, the sampling rate of 4 x NTSC color subcarrier (3.58 MHz), used at the very genesis of digital television equipment. See: 4:1:1, 4:2:0, 4:2:2, 4:4:4, 4fsc, Nyquist (frequency)
14:9 A picture aspect ratio that has been used as a preferred way to present 16:9 images on 4:3 screens. It avoids showing larger areas of black above and below letterboxed pictures but does include more of the 16:9 image than 4:3. It is commonly used for analog transmissions that are derived from 16:9 digital services.
16:9 Picture aspect ratio used for HDTV and some SDTV (usually digital). See also: 14:9, 4:3, Widescreen
24P Refers to 24 frames-per-second, progressive scan. 24 f/s has been the frame rate of motion picture film since talkies arrived. It is also one of the rates allowed for transmission in the DVB and ATSC digital television standards - so they can handle film without needing any frame-rate change (3:2 pull-down for 60 fields/s 'NTSC' systems or running film fast, at 25f/s, for 50 Hz 'PAL' systems). 24P is now accepted as a part of television production formats - usually associated with high definition 1080 lines to give a 'filmic' look on 60 Hz TV systems. See also: 24PsF, 25P, 3:2 Pull-down, ATSC, Common Image Format, DVB, Versioning
24PsF (segmented frame) A system for recording 24P images in which each image is segmented - recorded as odd lines followed by even lines. Unlike normal television, the odd and even lines are from an image that represents the same snapshot in time. It is analogous to the scanning of film for television. This way the signal is more compatible (than normal progressive) for use with video systems, e.g. VTRs, SDTI or HD-SDI connections, mixers/switchers etc., which may also handle interlaced scans. Also it can easily be viewed without the need to process the pictures to reduce 24-frame flicker. See also: Interlace Factor, Progressive
25P Refers to 25 f/s, progressive scan. Despite the international appeal of 24P, 25P is widely used for HD productions in Europe and other countries using 50 Hz TV systems. This is a direct follow-on from the practice of shooting film for television at 25 f/s. See also: 24P, 24PsF, Common Image Format, DVB
2K See Film formats 4:2:2
3:2 Pull-down (a.k.a. 2:3 Pull-down) A method used to map the 24 or 23.98 f/s of motion picture film onto 30 or 29.97 f/s (60 or 59/94 fields) television, so that one film frame
A ratio of sampling frequencies used to digitize the luminance and color difference components (Y, R-Y, B-Y) of an image signal. The term 4:2:2 denotes that for every four samples of the Y luminance, there are two
3Gig To meet the emerging demands of increased resolution for high-definition capture, transport, storage and production of video images, equipment is being offered with SMPTE 424M compliant physical layer connections supporting 2.97 Gb/s data rates, or 3Gig for short.
3G A marketing term derived from 3Gig but encompassing the 1080p standard
4:1:1 This is a set of sampling frequencies in the ratio 4:1:1, used to digitize the luminance and color difference components (Y, R-Y, B-Y) of a video signal. The 4 represents 13.5 MHz, (74.25 MHz at HD) the sampling frequency of Y, and the 1s each 3.75 MHz (18.5625) for R-Y and B-Y (i.e. R-Y and B-Y are each sampled once for every four samples of Y). With the color information sampled at half the rate of the 4:2:2 system, this is used as a more economic form of sampling where video data rates need to be reduce. 4:1:1 sampling is used in DVCPRO (625 and 525 formats), DVCAM (525/NTSC) and others. See also: 4:2:0, 4:2:2, DV (DVCAM and DVCPRO)
4:2:0 A sampling system used to digitize the luminance and color difference components (Y, R-Y, B-Y) of a video signal. The 4 represents the 13.5 MHz (74.25 MHz at HD) sampling frequency of Y while the R-Y and B-Y are sampled at 6.75 MHz (37.125 MHz) - effectively on every other line only (i.e. one line is sampled at 4:0:0, luminance only, and the next at 4:2:2). This is used in some 625-line systems where video data rate needs to be reduced. 4:2:0 is widely used in MPEG-2 coding meaning that the broadcast and DVD digital video seen at home is usually sampled this way. 625 DV and DVCAM coding also use 4:2:0. However the different H and V chroma bandwiths make it inappropriate for post applications. See also: 4:1:1, 4:2:2, DV (DVCAM), MPEG-2 occupies three TV fields, the next two, etc. It means the two fields of every other TV frame come from different film frames making operations such as rotoscoping impossible, and requiring care in editing.
3D (graphics) Applied to graphics, this describes graphics objects that are created and shown as three-dimensional objects. As computer power has increased, so has the ability to cost-effectively produce more and more detailed 3D graphic results - as seen in feature length animations. For television presentation, live 3D computer graphics is now commonplace - even in HD. The considerable computational power needed for this is generally supplied by GPUs.
3D (stereo) In television, film or cinema, 3D may refer to material that is shot using a set of 'stereo' cameras and shown on the screen as a pair of superimposed stereo images (usually 'decoded' by the viewer with polarized spectacles). Also known as stereo3D and stereoscopic 3D. See also: Stereoscope samples each of R-Y and B-Y, giving less chrominance (color) bandwidth in relation to luminance. This compares with 4:4:4 sampling where full same bandwidth is given to all three channels - in this case usually sampled as RGB. The term 4:2:2 originated from the ITU-R BT.601 digital video sampling where 4:2:2 sampling is the standard for digital studio equipment. The origin of the term is steeped in digital history and should strictly only be used to describe a specific format of standard definition digital television sampling. However, it is widely used to describe the sampling frequency ratios of image components (Y, B-Y, R-Y) of HD, film and other image formats. See also: 13.5 MHz, Co-sited sampling, Digital keying, ITU-R BT.601, ITU-R BT.709, Nyquist
4:2:2:4 This is the same as 4:2:2 but with the key signal (alpha channel) included as the fourth component, also sampled at 13.5 MHz (74.25 MHz at HD). See also: Dual link
4:3 The aspect ratio of PAL and NTSC traditional television pictures, originally chosen to match 35mm film. All broadcast television pictures were 4:3 until the introduction of high definition when a wider image was considered to be more absorbing for viewers. For display tube manufacturers the most efficient aspect ratio would be 1:1 - square - as this is inherently the strongest, uses less glass and weighs less. 16:9 tubes are more expensive to produce. Such restraints do not apply to panels basic on LED, Plasma or SED technologies.
4:4:4 One of the ratios of sampling frequencies used to digitize the luminance and color difference components (Y, B-Y, R-Y) or, more usually, the RGB components of a video signal. In this ratio there is always an equal number of samples of all components. RGB 4:4:4 is commonly used in standard computer platform-based equipment, when scanning film or for high-end post including that used for cinematography. In the converged media world, big screen requirements for cinema demand a new high level of picture quality. Film is commonly scanned in RGB for digital intermediate and effects work, and recorded directly to disks. The signal is then kept in the RGB form all the way through the DI process to the film recorder - making the best use of the full RGB data. For the rapidly growing market of digital cinema exhibition the DCI has recommended X'Y'Z'chromaticity which can be derived from RGB using a 3D LUT. See also: 2K, X'Y'Z', Digital intermediate, Dual link
4:4:4:4 As 4:4:4, except that the key signal (a.k.a. alpha channel) is included as a fourth component, also sampled at 13.5 MHz (74.25 MHz at HD). See also: Dual link
422P@ML See MPEG-2
4fsc A sampling rate locked to four times the frequency of color subcarrier (fsc). Its use is declining as all new digital equipment is based on component video where color subcarrier does not exist and sampling clock signals are derived from the line frequency. See also: Component video A 4K See Film formats
5.1 Audio See Discrete 5.1 Audio
50P and 60P These indicate a video format that has 50 or 60 progressive frames per second and usually refers to high definition. The original digital television standards only included progressive frame rates above 30 Hz for image sizes up to 720 lines - thus limiting the total video data. More recently this has been expanded up to 60 Hz for the larger 1080-line television standards to provide the best of the best - the maximum HD image size with a fast rate for rendition of fast action and progressive frames for optimum vertical resolution (better than interlaced scans). The baseband signal produces twice the data rates of the equivalent interlaced (50I and 60I) formats, pushing up equipment specifications. See also: SDI (3G SDI)
601
See ITU-R BT.601 709
See ITU-R BT.709 7.1
See Discrete 5.1 Audio
8 VSB/16 VSB See VSB