Symbols & number items
A slang term used to define the U-matic tape format developed in the 1970's by SONY Corp. Many tape formats are often referred to by the width of the tape. VHS is often called 1/2"
1”Analog reel to reel video tape format. Industry standard of the 1980’s. Called 1” because the tape is 1” wide.
Analog reel to
reel format, industry standard of the 1970’s. Called 2” because
the tape was 2” wide. Also known as “Quad”.
1)da Vinci color
enhancement system capable of up to 4K data, HDTV and SDTV processing.
The successor to 888 DUI. 2)Generic
term for data with a resolution of (about) 2000 pixels which is deemed
to be about 16 mm quality and good enough for many
35 mm applications.
The technique used to convert 24 frames per second film to 30 frames per second video. Every other film frame is held for 3 video fields resulting in a sequence of 3 fields, 2 fields, 3 fields,2 fields, etc. The full sequence is: A-frame = video fields 1&2, B-frame = video fields 1&2&1, C-frame = video fields 2&1, D-frame = video fields 2&1&2. (The letters correspond to film frames.) A frame sequence used to map 24 fps film to 30 fps video in which every second film frame is represented by three video fields instead of two. This leads to a set of ten video fields for each four film frames.
Four times the frequency of SC (subcarrier). The sampling rate of a D-2 digital video signal with respect to the subcarrier frequency of an NTSC or PAL analog video signal. The 4fsc frequency is 14.3 MHz in NTSC and 17.7 MHz in PAL.
4:1:1 means the Y’ component is sampled at 13.5 MHz and the color difference signals are each sampled at 3.375 MHz. Comment: This means 720 Y’ samples and 180 each of Cr and Cb samples in each scan line. Examples are NTSC DVC-Pro and DVCAM. Often misused to mean the same as 4:2:0.
4:2:0 means 2:1 horizontal and 2:1 vertical color downsampling. Comment: This actually means 720 Y’ samples per scan line and 320 Cr and Cb samples in every other scan line. Comment: An example is PAL DV.
4:2:2A serial digital video signal having a Y’ luminance component sample rate of 4 times 3.375 MHz (which is approximately the frequency of the NTSC color subcarrier) and the two Cr and Cb color difference signals sampled at 2x3.375 MHz. Comment: 4:2:2 takes advantage of the eye’s different sensitivity to color vs. brightness. 4:2:2 implies 2:1 horizontal color downsampling and no vertical color downsampling, or 720 Y’ samples and 360 Cr and Cb samples in a scan line. After overhead, the total bit rate is 270 Mb/s. Examples are D1, Digital Betacam, D5, DVCPro 50, and DCT 700d; these formats are incompatible. 4:2:2 Profile at Main Level (422P@ML) has been made a part of MPEG-2. The details of the format are specified in the ITU-R BT.601-2 standard document.
See also: ITU-R BT.601-2.
Same as 4:2:2, but with the addition of a key channel that is sampled four times for every four samples of the luminance channel.
4:4:4 means that the Y’, Cb, and Cr components are each sampled at 13.5 MHz. This sampling rate also applies to equiband RGB signals. Comment: A commercial example is the latest DVC‑Pro (D7).
Similar to 4:2:2:4, except that for every four luminance samples, the color and key channels are also sampled four times.
A type of surround sound. Six discrete audio
channels are used: Left, Center, Right, Left Rear (or side) Surround,
Right Rear (or side) Surround, and a subwoofer (considered the ".1"
as it is limited in bandwidth).
22:11:11 is the high definition equivalent of
4:2:2, assuming the same clock rates.
22:22:22 is the high definition equivalent of 4:4:4.
ITU-R BT. 709-3, formerly CCIR Rec. 709. Parameter Values for the HDTV Standards for Production and International Programme Exchange. Specifies parameter values for chromaticity, sampling, signal format, frame rates, etc., of high definition television signals.
One of the standard quantization levels used in digital video standards, offering 256 levels of gray scale video. The CCIR-601 digital video standard specifies the range from black (level 16) to white (level 235). The number of levels available in a typical digital video signal. 8-bit offers 255 levels. D1 is 8 bit.
1. The sampling ratio of da Vinci digital color enhancement systems, well above current recording standards, in order to produce film like images even after extreme manipulations. 2. The da Vinci Digital Unified Color Corrector ( because of point 1. above ) da Vinci is the only manufacturer working in the 8:8:8 domain.
Eight discrete amplitude level vestigial side-band
broadcast transmission technology, used in the ATSC digital television
Higher precision quantization level used in digital video standards, offering 1024 levels of gray scale video. A term used in specifications of digital-to-analog (DAC) converters found with video encoders normally indicative of high-performance, high-precision equipment. Also, the number of levels available in a digital video signal. 10-bit offers 1023 levels, four times the accuracy of 8-bit, and vastly superior for telecine transfers and chroma-keying.
16 x 9
A wide screen television format in which the aspect ratio of the screen is 16 units wide by 9 high as opposed to the 4x3 of normal TV
525/60 Com ponent Video
A reference to the line and field rate of Y, R-Y, B-Y component video. (See also: NTSC, component video)
ITU-R Rec. BT. 601-5, formerly known as CCIR 601. This recommendation developed by the International Radio Consultative Committee for the digitization of studio color video signals deals with color space conversion from R'G'B' to Y'CrCb, the digital filters used for bandwidth limiting, the sample rate (defined as 4:2:2 at 13.5 MHz), the horizontal resolution (720 active samples for NTSC and PAL), and related issues. Interface issues are defined in ITU-R BT. 656.
625/50 Component Video
A reference to the line and field rate of Y, R-Y, B-Y component video. (See also: PAL, component video)
ITU-R Rec. BT. 1361. Successor to the colorimetry component of ITU-R BT. 709-3, with which it is transport compatible, but which redefines the range of tristimulus codewords, using negative RGB signals, and thereby expands the color gamut while keeping the 709 primaries.
1394b, aka FireWire™, i.LINK™. An isochronous or asynchronous serial memory bus for connecting computer peripherals at speeds up to 100 Mb/s for up to 100m on copper and 800 Mb/s over optical fiber.
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