Tektronix 2200 Manual Do Utilizador

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Glossary
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Caption:  
See Title.
Character Generator:  
An electronic device 
that produces letters, numbers, and 
symbols for video output.
Chroma: 
 The attribute of light combining 
hue and saturation, independent of 
intensity. The color perceived is 
determined by the relative proportions of 
the three primary colors.
Chroma Key:  
A key effect in which the key 
signal is derived from the chroma 
information (hue and saturation) of the 
key source.
Chroma Key Shadow:  
A video effect in 
which the shadows in a keyed-out portion 
of a picture can be restored on the 
background of the composite picture.
Chrominance:  
The colorimetric difference 
between any color and a reference color of 
equal luminance. Chrominance 
corresponds to the sensation of saturation.
CIE Colors:  
A color standard 
recommended by the IEEE.
Clip:  
A threshold level adjustment to 
which the key source attribute (luminance, 
chrominance, etc.) is compared for 
generating the internal key signal. The 
(CLIP)
 control sets the switching point 
between the background and the fill.
CMOS (Complementary Metal Oxide 
Semiconductor):  
A family of 
semiconductors characterized by low 
power consumption.
Color Bars: 
 Standard color test signal of 
(usually) eight colors.
Color Black:  
A video signal in which the 
luminance is at the Black reference level.
Color Burst:  
A nine-cycle (NTSC) or ten-
cycle (PAL) burst of subcarrier on the 
video signal which serves as the reference 
for establishing the picture color.
Color Difference Signal:  
A video signal 
conveying only color information such as 
R-Y and B-Y.
Color Frame:  
The video frame polarity. In 
order to keep the video signal in phase, 
color frames must alternate polarity with 
each frame.
Component:  
A part of an assembly. (Also 
see Assembly and System.)
Component Video:   
A set of video signals 
(usually three), each of which represents a 
portion of the information needed to 
generate a full color image. 
Composite Video:   
A video signal which 
contains both picture and sync 
information. (Also see Encoded Video.)
Control Signal:  
A signal used to control 
some aspect of switcher operation, such as 
video path selection and manipulation, 
inter-processor communications, and 
variable control (knob) monitoring.