Sony Tektronix WFM 1125, Руководство пользователя

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Glossary
Glossary-2
WFM 1125 Option 0A/0B/0C/0D User Manual
Composite Video
A single video signal containing all of the necessary information to repro-
duce a color picture. Created by adding quadrature amplitude modulated
R–Y and B–Y to the luminance signal for NTSC systems or U and V to the
luminance signal for PAL systems.
CRC
Cyclic Redundancy Code.
dB (Decibel)
A decibel is a logarithmic unit used to describe signal ratios. For voltages,
dB = 20 Log
10
(V
1
/V
2
).
EDH
Error detection and handling. Supports the standard SMPTE RP-165, which
proposes a technique for recognizing inaccuracies in the serial digital signal.
Field
In interlaced scan systems, the information for one picture is divided up into
two fields. Each field contains one half of the lines required to produce the
entire picture. Adjacent lines in the picture are in alternate fields.
Frame
Contains all the information required for a complete picture. For interlaced
scan systems, there are two fields in a frame.
Gamma
A measure that compares the contrast in the original and reproduced
television picture. Since picture monitors have a nonlinear relationship
between the input voltage and brightness, the signal must be correspondingly
enhanced to nullify the nonlinear distortion. Gamma correction is always
done at the source (camera) in television systems: the R, G, and B signals are
converted to R
1
/
V
, G
1
/
V
, and B
1
/
V
. Values of about 2.2 are typically used for
gamma.
Gamut
See Color Gamut.
GBR
See RGB.
Graticule
The scale which is used to quantify the information on a waveform monitor
or vectorscope display. Graticules may either be screened onto the faceplate
of the CRT itself (internal graticule), or onto a piece of glass or plastic which
fits in front of the CRT (external graticule). They can also be electronically
generated.
Hue
The property of color that allows us to distinguish between colors such as
red, yellow, purple, etc.