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CHAPTER 2 NEW FUNCTIONS
2-21
COPYRIGHT© 2001 CANON INC.
2000 2000 2000 2000
CANON iR8500 REV.0 MAR. 2001
2.2.6 Digital Image Processing
Digital image processing is performed on the reader controller PCB, and it includes the
following major functions:
• Executing shading correction
• Executing auto density correction
• Executing data conversion from 4-channel image data to 2-channel image data
[1] First half even-number pixel digital image signal
[2] First half odd-number pixel digital image signal
[3] Last half even-number pixel digital image signal
[4] Last half odd-number pixel digital image signal
[5] Even-number pixel digital image signal
[6] Odd-number pixel digital image signal
F02-202-04
Gain/offset
correction data
EEP-ROM
SRAM
CPU
IC
CCD/AP
PCB
Reader controller PCB
10bit
10
10
10
8bit
8
Target value
J1502
J1107
J1103
J1901
[1]
[2]
Main
controller
PCB
Original
orientation
detection
PCB
[5]
[6]
[3]
[4]
Shading correction
Auto density correction
Image data
4-channel-to-2-channel
conversion
Dust detection (IC)
Chapter_02_1.p65
01/03/13, 16:35
21
Summary of Contents for ImageRunner iR8500 Series
Page 492: ...COPYRIGHT 2001 CANON INC 2000 2000 2000 2000 CANON iR8500 REV 0 MAR 2001 APPENDIX ...
Page 497: ...Service Mode COPYRIGHT 2001 CANON INC 2000 CANON iR8500 REV 0 MAR 2001 ...
Page 620: ...Error Code COPYRIGHT 2001 CANON INC 2000 CANON iR8500 REV 0 MAR 2001 ...
Page 655: ...PRINTED IN U S A 0301AB0 76 0 This publication is printed on 100 recycled paper ...