Tektronix VM5000 Series, Быстрый старт Руководство пользователя

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Applications
Applications
Simple Color Bars Measurement – Options SD/HD
Amplitude measurements are typically performed using the color bars test signal, which switches the R ′ G ′ B ′ components on
and off to produce all eight possible color combinations (White, Yellow, Cyan, Green, Magenta, Red, Blue, and Black). There
are a variety of different forms of the color bar test signal, typically either using a maximum dynamic range of 700 mV = 100%
or at 75% with an R
′ G ′ B ′ amplitude of 525 mV. In the following tables, the amplitude ranges for the component Y ′ P ′ bP ′ r are
given for the various standards of 100% and 75% color bars.
Amplitude ranges for various 100% color bar signal formats
480p/576p 1080/720
Color bar
R ′
(mV)
G ′
(mV)
B ′
(mV)
Y ′
(mV)
P ′ b
(mV)
P ′ r
(mV)
Y ′
(mV)
P ′ b
(mV)
P ′ r
(mV)
White 700 700 700 700.0 0.0 0.0 700.0 0.0 0.0
Yellow 700 700 0 620.2 -349.8 56.9 649.5 -350.0 32.1
Cyan
0 700 700 490.7 118.0 -349.9 551.2 80.2 -350.0
Green 0 700 0 410.9 -231.7 -293.0 500.6 -269.8 -317.9
Magenta 700 0 700 289.1 231.7 293.0 199.4 269.8 317.9
Red 700 0 0 209.3 -118.0 349.9 148.8 -80.2 350.0
Blue 0 0 700 79.8 349.8 -56.9 50.5 350.0 -32.1
Black 0 0 0 0.0 0.0 0.0 0.0 0.0 0.0
Amplitude ranges for various 75% color bar signal formats
480p/576p 1080/720
Color bar
R ′
(mV)
G ′
(mV)
B ′
(mV)
Y ′
(mV)
P ′ b
(mV)
P ′ r
(mV)
Y ′
(mV)
P ′ b
(mV)
P ′ r
(mV)
White 700 700 700 700.0 0.0 0.0 700.0 0.0 0.0
Yellow 525 525 0 465.2 -262.3 42.7 487.1 -262.5 24.1
Cyan 0 525 525 368.0 88.5 -262.4 413.4 60.2 -262.5
Green 0 525 0 308.2 -173.8 -219.7 375.5 -202.3 -238.4
Magenta 525 0 525 216.8 173.8 219.7 149.5 202.3 238.4
Red 525 0 0 157.0 -88.5 262.4 111.6 -60.2 262.5
Blue 0 0 525 59.9 262.3 -42.7 37.9 262.5 -24.1
Black 0 0 0 0.0 0.0 0.0 0.0 0.0 0.0
Depending on the type of equipment being tested, a variance in the actual values is allowed. For example, the progressive
outputs of DVD players can introduce setup to their outputs that can vary the overall measured results. Variations in the
level of the components can introduce different hue and saturation in the displayed picture. The color bar test signal lets
you check for gain inequalities between the channels and to ensure that the signal is not distorted, which could produce
severe clipping of the signal.
48 VM Series Video Measurement System Quick Start User Manual