20 June 2005
IMAGE PROCESSING
6-25
Detailed
Descriptions
Text/Photo Mode
Text/Photo mode achieves high quality reproduction of pictures with accurate
grayscaling. Processing is conducted with the special
γ
coefficient which
reproduces a wide range of grayscale. Compared with the Text mode, text
reproduced in the Text/Photo mode appears lighter and textured backgrounds
could appear on copies, but the incidence of moiré is reduced with and edge
detection filter. Because Photo Priority uses an MTF filter weaker than that of the
Normal setting, the quality of the image is improved with the elimination of moiré.
The Text Priority selection uses an MTF filter stronger than that of the Normal
setting, thus increasing the sharpness of lines.
Image Processing Flow
Related SP Modes
Scanner Image
Correction
Shading Correction
Ð
Pre-Filter
Processing
Background Erase
SP4903 67 (Background Erase Level:
Text/Photo Mode)
Ð
Pre-Filter
Smoothing
SP4903 13 (Pre-Filter: Text/Photo)
Ð
Magnification
Main Scan Direction
SP2909 1 (Main Scan Magnification)
Ð
Independent Dot Erase
SP4903 62 (Independent Dot Erase Level)
Ð
Filter Processing
MTF Correction
SP4904 25~28 Text/Photo (General) Quality
(
”Text Photo Mode”, pg.6-36)
Ð
Density Control
γ
Coefficient
Ð
Grayscale
Processing
Error Diffusion
NOTE:
An SP code number and name set in
bold italic
denotes an SSP (Special
Service Program) mode. To access an SSP, enter the SP mode: press and
hold down
on the 10-key pad then “Copy SP” on the touch-screen.
