Image Processing Steps And Related Sp Modes; Text Mode - Ricoh B291 Service Manual

IMAGE PROCESSING

6.5.7 IMAGE PROCESSING STEPS AND RELATED SP MODES

Text Mode

The Text mode achieves quality reproduction of text and sharp lines and ignores
background texture. Processing is conducted with a high resolution MTF filter;
special processing with the γ coefficient prevents background reproduction and
achieves the best reproduction of images with error diffusion. Because the Soft and
Normal settings use a weak MTF filter, the quality of the image is improved with the
elimination of moiré. The Sharp selection uses an MTF filter stronger than that of
the Normal setting, thus increasing the sharpness of lines.
Image Processing Flow
Scanner Image
Correction
Pre-Filter
Processing
Magnification
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.
B291/B295/B296/B297
CÓPIA NÃO CONTROLADA
Shading Correction
!
Background Erase
!
Pre-Filter Smoothing
!
Main Scan Direction
!
Independent Dot Erase
!
MTF Correction
!
γ Coefficient
!
Error Diffusion
CÓPIA NÃO CONTROLADA
Related SP Modes
SP4903 65 (Background Erase Level: Text Mode)
SP4903 10 (Pre-Filter: Text)
SP2909 1 (Main Scan Magnification)
SP4903 60 (Independent Dot Erase: Text Mode)
SP4904 20~23 Text (!General Quality pg. .6-34)
6-24 SM