Printer Output Image Processing - Canon iR C6800 Series Service Manual

4.5.5 Printer Output Image Processing

Main controller PCB processes image data from the Reader unit for output to the printer.
If ACS identifies the original
as being black-and-white,
the machine generates
the Bk signal here.
(Otherwise, the data is
let to pass through the block.)
If color mode is selected,
the Bk signal is generated here.
The text area is subjected
to UCR processing.
The correction LUT is prepared
as part of PASCAL control.
Y,M,C,Bk
To DC controller
PCB
F-4-16
Reader unit
RGB
Main controller PCB (sub)
RGB 24
Main controller
PCB (man)
RGB 24
- background removal (AE)
- Bk generation
RGB-to-CMY conversion
output direct mapping
CMYK
- F value adjustment
- color balance correction
output gamma correction
Best screen selection
Smoothing
- framing
- blanking
Y,M,C,Bk 24
- image data serial/
parallel conversion
- video count
24
area signal
area signal
area signal
Chapter 4
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