Barco Projector Toolset, Справочное руководство

Страница: 133 / 245

8. Configurator, Projector adjustment settings
Image 8-21
Custom aspect ratio
8.5.9 Input balance
8.5.9.1 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 8-22 , 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 reposi-
tioning 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 unbal-
anced, image 8-23
B
Black level
0.7V
Image 8-22
Black level
Δ G
ΔΒ
Δ R
R
G
B
Image 8-23
R5976924 PROJECTOR TOOLSET 16/04/2009 129