Tektronix 2200 Manual Do Utilizador

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Glossary
G-7
Hue:  
The attribute of light (wavelength, 
frequency) which determines the color 
perceived (red, blue, green etc). Specified 
by phase relationship to color burst in 
composite video. Any saturated color 
which is not one of the three primaries 
may be treated as a combination of two 
primaries.
I
Insert Key:  
A key in which a portion of the 
background signal is replaced with an 
insert (fill) signal.
Interrupt:  
A special control signal which 
informs the CPU that its attention is 
needed for some type of exception 
processing.
J
Jog:  
The process of moving a videotape 
forward or backward at a variable rate of 
speed.
K
Key: 
 (1) An effect in which a portion of the 
background video picture is replaced by 
another picture or caption (2) The signal 
which is used to pass or block portions of 
the background and fill video signals.
Keyboard:  
A small control panel with 
pushbutton keys that provides the human 
interface into an electronics system.
Key Fill:  
In a key effect, the video signal 
that is said to “fill the hole” cut in 
background video by the key source. Key 
fill may be key video, modified key video, 
or matte.
Key Invert:  
(1) A key mode which inverts 
the polarity of the key to allow dark areas 
of the source video to cut holes in 
background. (2) A chroma key mode 
which inverts the foreground and 
background fill positions.
Key Source:  
The source of the signal which 
is said to “cut the hole” in the background 
scene for a key effect. This signal is 
processed into a key which controls the 
video mix between the background scene 
and the fill video; thus the key source 
determines the shape of the key effect.
Key Video:   
The video selected on a key bus 
which may be the key fill, the key source, 
or both.
L
Learn:  
The operation of storage in an 
E-MEM system.
Lever Arm Transition:  
A transition between 
primary video and/or title video signals 
made by manually moving the lever arm.
Linear Key:  
A key which is processed at or 
near unity gain by the switcher. Clip and 
gain control have very small adjustment 
ranges, and keying is performed using the 
luminance values of the linear key source. 
A Linear Key is normally used when the 
key has already been properly shaped at 
the key source.