Text/Photo Mode - Ricoh B264 Service Manual

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
Scanner Image Shading Correction
Correction
Pre-Filter
Background Erase
Processing
Pre-Filter Smoothing
Magnification Main Scan Direction
Independent Dot Erase
Filter Processing
Density Control
Grayscale
Processing
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.
SM
Related SP Modes
SP4903 67 (Background Erase Level:
Text/Photo Mode)
SP4903 13 (Pre-Filter: Text/Photo)
SP2909 1 (Main Scan Magnification)
SP4903 62 (Independent Dot Erase Level)
MTF Correction SP4904 25~28 Text/Photo (General) Quality
( "Text Photo Mode", pg.6-36)
γ Coefficient
Error Diffusion
6-25
IMAGE PROCESSING
B264/B265