Extron Electronics MS9500 HD FrEND Plus - Manual (Page 109)

MS950GL HD FrEND Plus Glossary
ITU-R 601, 4:2:2 is the standard for digital studio equipment and the terms
"4:2:2" and "601" are commonly (but technically incorrectly) used
synonymously. The sampling frequency of Y is 13.5 MHz and that of R-Y and
B-Y is each 6.75 MHz providing a maximum color bandwidth of 3.37 MHz-
enough for high-quality chromakeying. The format specifies eight bits of
resolution.
The details of the format are specified in the ITU-R BT.601-2 standard
document. See also: ITU-R BT.601-2.
4:4:4 Similar to 4:2:2, except that for every four luminance samples, the color
channels are also sampled four times
5.1 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).
See also: Dolby Digital.
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