Ipu (Image Processing Unit); Overview - Ricoh Aficio 220 Service Manual

IMAGE PROCESSING 20 September 1999

2.2.4 IPU (IMAGE PROCESSING UNIT)

Overview

BICU
Fax Controller
S c a n n e r
IPU
SBU
Controller
Printer Controller
M e m o r y
LDD
E M B
Controller
FCI
LD
V C U
D R A M
A265D503.WMF
The image data from the SBU goes to the IPU (Image Processing Unit) IC on the
BICU board, which carries out the following processes on the image data.
1. Auto shading
2. Scanner gamma correction
3. Filtering (MTF and smoothing)
4. Magnification
5. ID gamma correction
6. Grayscale processing
7. Binary picture processing
8. Error diffusion
9. Dithering
10. Video path control
11. Test pattern generation
The image data then goes to the LD driver (LDD).
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