D. IEU (IMAGE ENHANCEMENT UNIT)
D.1. OVERVIEW
The IEU processes Photo/Text separation and Binary conversion
automatically.
•
Automatic Photo/Text Separation: To improve image reproduction of
Photo/Text documents, text and photo areas are distinguished
automatically and the appropriate image processing is done on them.
•
Automatic Binary Conversion: To improve image reproduction of text
which is printed in various densities, the density is detected
automatically and the threshold level is adjusted accordingly.
D.2. BLOCK DIAGRAM
The IEU consists of the following 8 blocks.
1. DIB (Video Data Input Block)
The DIB has the following functions: controlling the input of multi-value (8 bit)
video data, generating the line reset signal and the page reset signal, and
transmitting multi-value video data to the GTB.
2. BIB (Binary Video Data Input Block)
The BIB has the following functions: controlling the binary video input data,
adjusting the delay time for each pixel, and transmitting multi-value video
data to the DOB.
Multi-value
Video Data
Binary Video
Data
CPU
Reference
Clock
DIB
BIB
CIB
TGB
GTB
IPB
ZMB
DOB
IEU Video
Data
+5V
GND
Others
FIFO
SRAM
G404O500.WMF
Appendix D
October 9th, 1995
IEU (IMAGE ENHANCEMENT UNIT)
OVERVIEW
D-1