Barco CineVERSUM 110, Руководство пользователя

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8. Image Menu
Image 8-27
8.8 Input Balance
Overview
• Introduction to Input Balance
• Adjusting the input balance
• Input balance for YPrPb signals
8.8.1 Introduction to Input Balance
Introduction: Unbalanced color signals
When transporting signals, there is always a risk of deterioration of the information contained in the signals.
In case of information contained in the amplitude of the signals which is the case of data color signals (R, G, B),image 8-28 , we are
quite sure that the amplitude of these color signals is subject to alterations.
An example of alteration may be a DC component added to the signal, in the form of a DC offset repositioning the black level, since
this
black level ( “brightness” ) will become crucial later on (clamping circuit) it will result in “black not being black”.
Another value that is subject to alteration is the amplitude of the signal, resulting in an altered “Gain” of the signal ( “white level” or
contrast ).
The alterations of the three color signals will happen independently i.e. the colors will end to be unbalanced, image 8-29
B
Black leve
0.7V
Image 8-28
Black leve
∆
G
∆Β
∆
R
R
G
B
Image 8-29
76 R5976697 CINEVERSUM™ 110 12/05/2004