Toshiba e-studio 250 - SLG Board; Features; Functions of the Image Processing Circuit

December 2002 TOSHIBA TEC 6 - 3 e-STUDIO160/200/250 IMAGE PROCESSING
6.3 SLG Board
6.3.1 Features
(1) The image processing ASIC is controller by the CPU on the SLG board.
(2) The SLG board implements the following image processing functions.
• High quality image processing
• Image memory editing
• Editing processing
• Gamma correction processing
• Tone processing
• External output systems interface
6.3.2 Functions of the image processing circuit
The image processing ASIC installed on the SLG board implements the following functions.
(1) High quality image processing
A. Range correction
This function converts the image signal to density range width and corrects it to match each origi-
nal. When making a copy of originals with a certain level of background such as newspapers, this
function can reduce the background density.
Fig. 6-3-1 Histogram
Dynamic range width Extended dynamic rage width
Back-
ground
After range
correction
Text
Smaller No. of pixels Larger
Lower Density Higher Lower Density Higher
Smaller No. of pixels Larger
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