9. Image
9.3.7.1
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 9-29 , 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 9-30
B
Black level
0.7V
Image 9-29
Black level
Δ
G
ΔΒ
Δ
R
R
G
B
Image 9-30
One can conclude here that a good color tracking can only be met by using three previously (input) balanced
color signals
Analog Digital Conversion
The analog color signals must pass through an Analog/Digital conversion circuit prior to any digital processing in the PMP.
A typical ADC transforms the analog value into an 8 bit coded digital signal.
The graphic shows that when converting a signal containing a DC offset component the range of the converter is not optimally used.
Black level
Δ
R
ADC
0
255
i1 : superfluous information
i2 : video information
Image 9-31
One can 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.
R5905158 HDF SERIES 08/12/2016
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Summary of Contents for HDF W22
Page 4: ......
Page 10: ...Table of contents 6 R5905158 HDF SERIES 08 12 2016 ...
Page 18: ...1 Safety PR Image 1 2 14 R5905158 HDF SERIES 08 12 2016 ...
Page 32: ...2 Configurations requirements and restrictions 28 R5905158 HDF SERIES 08 12 2016 ...
Page 78: ...5 Getting started 5 8 Projector Address 74 R5905158 HDF SERIES 08 12 2016 ...
Page 84: ...5 Getting started 80 R5905158 HDF SERIES 08 12 2016 ...
Page 102: ...7 Start up of the adjustment mode 98 R5905158 HDF SERIES 08 12 2016 ...
Page 105: ...8 Input Line Alternating 3G Second input R5905158 HDF SERIES 08 12 2016 101 ...
Page 138: ...8 Input Image 8 64 3D auto detection 134 R5905158 HDF SERIES 08 12 2016 ...
Page 144: ...8 Input 140 R5905158 HDF SERIES 08 12 2016 ...
Page 158: ...9 Image 9 3 7 Input Balance 154 R5905158 HDF SERIES 08 12 2016 ...
Page 167: ...9 Image 9 5 Timings R5905158 HDF SERIES 08 12 2016 163 ...
Page 171: ...9 Image 9 6 Image File Services R5905158 HDF SERIES 08 12 2016 167 ...
Page 176: ...9 Image No recovery possible 172 R5905158 HDF SERIES 08 12 2016 ...
Page 224: ...11 Lamp 220 R5905158 HDF SERIES 08 12 2016 ...
Page 227: ...12 Alignment Pan Tilt Store setting per layout R5905158 HDF SERIES 08 12 2016 223 ...
Page 244: ...12 Alignment 6 Rotate 7 Rotation point 240 R5905158 HDF SERIES 08 12 2016 ...
Page 254: ...12 Alignment 2 Use the or key to change the opacity 250 R5905158 HDF SERIES 08 12 2016 ...
Page 271: ...12 Alignment 12 14 Scenergix R5905158 HDF SERIES 08 12 2016 267 ...
Page 355: ...13 Projector Control 13 15 FLEX light output configuration R5905158 HDF SERIES 08 12 2016 351 ...
Page 368: ...14 Service Image 14 7 Diagnosis versions list 364 R5905158 HDF SERIES 08 12 2016 ...
Page 372: ...14 Service Image 14 21 Lamp power supply logging 368 R5905158 HDF SERIES 08 12 2016 ...
Page 394: ...15 Maintenance 390 R5905158 HDF SERIES 08 12 2016 ...
Page 404: ...16 Removal and installation of the projector covers 400 R5905158 HDF SERIES 08 12 2016 ...
Page 417: ...A Specifications A SPECIFICATIONS R5905158 HDF SERIES 08 12 2016 413 ...
Page 418: ...A Specifications 414 R5905158 HDF SERIES 08 12 2016 ...
Page 426: ...A Specifications 422 R5905158 HDF SERIES 08 12 2016 ...
Page 431: ...C Standard source files C STANDARD SOURCE FILES R5905158 HDF SERIES 08 12 2016 427 ...
Page 432: ...C Standard source files 428 R5905158 HDF SERIES 08 12 2016 ...
Page 436: ...C Standard source files 432 R5905158 HDF SERIES 08 12 2016 ...