Image Processing; Overview - Gestetner B130 Service Manual

IMAGE PROCESSING

6.11 IMAGE PROCESSING

6.11.1 OVERVIEW

Drum
LDD
The scanned image is processed by the following modules.
In the SBU
• CCD:
Converts the reflected light from the image into an analog signal. Driven
by the CDM (CCD Drive Module) on the VPL.
• Amp:
Amplifies the analog signal and sends it to the VPL on the FCU as a
digital signal.
In the VPL chip on the FCU
• VPU:
Video correction (black level, shading, peak tracking and correction),
image correction (gamma correction), and reduction processing (in
main-scan direction). (
• IPU:
Magnification processing (in main scan direction), filtering, second
gamma correction (for fax only), etc. (
• LIF
Smoothing, edge correction, FCI (fine character adjustment) (
The data then moves to the LD drive board in accordance with timing controlled by
the FCU.
Note the following:
• The VPU and IPU are submodules of a larger module, the VPM (Video
Processing Module). The VPM includes interface components (not shown)
that interface these submodules to the VRAM processing memory.
• The VPC (Video Path Control circuit) controls which signal is sent to the LIF.
• Abbreviations: SBU = Sensor Board Unit; LIF = Laser Interface; VPU = Video
Processing Unit; IPU = Image Processing Unit.
B129 Series/B044 Series
CÓPIA NÃO CONTROLADA
VRAM
CDM
V
IPU
FCI
P
C
LIF
VPL
FCU
Optional Printer Controller
6.8.2)
6-20
CÓPIA NÃO CONTROLADA
C
Amp
C
D
SBU
Video
Processing
VPU
VPM
6.8.2)
Optional
DIMM
B046D100.WMF
6.8.2)
SM