Specifications

Glossary
VTM-200 Installation and Operation Handbook E-5
Gamma This term applies to the linearity of the change from black to white. Gamma
controls adjust the gray or 50% point of the video either up or down, with the effect of
changing the gray level of the video.
Gamut The whole or total of whatever is being addressed. In color space, gamut refers
to all colors which are included in a particularly defined color group, such as 601
gamut.
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.
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.
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.