Digital Image Processing; Outline - Canon Image Reader-A1 iR5000i Service Manual

CHAPTER 2 MAIN CONTROLLER

2. Digital Image Processing

2.1 Outline

The machine's digital image processing and control of the image memory is performed by
the main controller PCB. The following is a block diagram showing digital image process-
ing:
Reader PG
Density conversion
(LUT)
Binary processing
(error division; text,
text/photo, print photo)
2-8 S
Reader unit
8
Enlargement/reduction
(main scanning direction)
8
Edge emphasis
8
Editing
8
Luminance/density
conversion (LOG conversion)
8
Density adjustment
(F-value conversion)
8
Density correction
(ϒ conversion)
8
1
Image memory
control
1
Print PG
Binary-binary density conversion
1
Smoothing
4 or 2
Thickening
4 or 2
Printer unit
F02-201-01
COPYRIGHT © 2001 CANON INC.
Image data
after shading
Binary processing
(dither screen; print photo)
1
Compression/
decompression,
rotation, enlargement/
reduction
SDRAM
I/O control
2000 2000 2000 2000 CANON iR5000i/iR6000i REV.0 JUNE 2001
HDD
Image server