12. Advanced Settings
B

Black level

0.7V

Image12-1
Black level
∆
G
∆Β
∆
R
R
GB
Image12-2
Onecan conclude here that a good color tracking can only be met by using three pre viously (input) balanced
color signals

Analog Digital Conversion

Theanalog color signals must pass through an Analog/Digital conversion circuit prior to any digital processing in the PMP.
Atypical ADC transforms the an alogvalue into an 8 bit co ded digitals ignal.
Thegraphic shows that when converting a signal containing a DC offset component the range of the converter is not optimally used.
Black level
∆
R
ADC
0
255
i1 : superfleous information
i2 : video information
Image12-3
Onecan conclude here that a good data conversion can only be met by using three previously (input) balanced
color signals

The objective of input balancing

The objective in input balancing is to “set” the same black level and the same white level for the three colors of a particular input
source.
Black level setting : brightness
White level setting : contrast
The same absolute black and white level for the three colors allow the same reference for Brightness and contrast control of the
picture !
These two references also set the range in which the ADC willwork for that particular source (this explains also why each input
balances ettingis linked to a particular source and thus saved in the image file).
66 R5976672 SOLARISLC40 13/01/2005