December 2002 TOSHIBA TEC 6 - 5 e-STUDIO160/200/250 IMAGE PROCESSING
(b) High-pass filter circuit
When an original with sharp image edges (text originals, etc.) is optically scanned and its image
signals are output through the CCD, the edges tend to become dull due to the characteristics of the
lens used and other reasons.
To compensate for this phenomenon, edge enhancement operation is performed on the differ-
ences in density between the target pixel and its adjacent ones to obtain an image with high
reproducibility of the original.
(3) Image memory editing
Editing functions such as enlargement/reduction and mirror image are performed using line memory.
The line memory is used for storing one line of pixel data in the primary scanning direction, and
updated with new pixel data each time the next line is scanned.
(a) Enlargement/reduction
This function is accomplished by using line memory control in a part of operations.
<Example> Enlargement
Solid black area
Original
Image signal
After correction
Low contrast area
<Example> Reduction
1100%
200%
2345678910
1122334455
1100%
50%
2345678910
13579
07006
07007
07008
To Next Page
Loading...
