Imagine Videotek VTM-2400, Инструкция по установке и эксплуатации

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Glossary
VTM-2400 Installation and Operation Handbook 119
Genlock (Generator Lock)
A method of synchronization involving the generation of a
video signal that is time and phase locked with another signal.
GPI
General Purpose Interface
Headend
In a cable TV system, the facilities where program sources (satellite, terrestrial,
VTR, local) are received and remodulated for distribution through a cable plant.
High Definition Television (HDTV)
High definition television has a resolution of
approximately twice that of conventional television in both the horizontal (H) and vertical (V)
dimensions and a picture aspect ratio (H to V) of 16:9.
High Level
A range of allowed picture parameters defined by the MPEG-2 video coding
specification which corresponds to high definition television.
HRC
Harmonically-Related Carrier
Hue
Color tint
ICPM
Incidental Carrier Phase Modulation. A measurement of picture carrier phase distortion
(affected by the video signal level) that occurs in the transmitter.
IP
Internet Protocol
IRC
Incrementally-Related Carrier
I.R.E.
Refers to the Institute of Radio Engineers, and is used as a unit of measurement. In
NTSC television, 1 volt of signal equals 140 IRE units.
ISP
Internet Service Provider
Jitter
A deformation of a signal affected by poor synchronization.
Key
An effect in television where a selected portion of background video is removed and
replaced with another video.
Key Cut
In a key effect, this is the video which designates the portion of background video
which is removed.
Key Fill
In a key effect, this is the video which is used to replace the portion of background
video which was removed. This may be the same video as the Key Cut video.
Key Invert
In a key effect, this is an electronic action which reverses the polarity of the key
cut signal. It makes black appear as white, and white appear as black.
Key Mask
In a key effect, it uses a wipe pattern from the wipe pattern generator to restrict
the key cut from removing video in a portion of the screen. This requires the use of the wipe
pattern generator and the Mask/Preset Size controls.
Key Source
Another term which is the same as key cut.
Legalization
The modification of serial digital video to conform to analog color space rules,
as required by users.
LCD
Liquid Crystal Display
LED
Light-Emitting Diode
LFE
Low Frequency Effects