Fujitsu M3097DG, Руководство OEM

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Image Functions
3-16
(3) Dynamic Threshold Curve
[A.4.7 SET WINDOW command/DTC mode]
For the Dynamic Threshold function, the threshold is changed with the average optical density of
a small area (e.g. 5 x 5 pixel area).
Relation between the threshold and maximum density is formed as a curve when the threshold is
expressed in the Y-axis and the maximum density in the X-axis. This curve is called “threshold
curve”.
This function allows a customer to select a threshold curve. Several different curves are prepared, one
is the OCR type and other is the image type. The characteristic of the curve is deferent between IPC-
2D and IPC-3D.
IPC-2D: The image type curve has steeper inclination in the middle of the curve. For OCR type
curve, the customer can select type (inclination) and density level.
PC-3D: 8 curves are available which adjusts the sensitivity of the image
The parameter of Dynamic Threshold are as follows.
Table 3.9 The deference of Dynamic Threshold Curve parameter
Option Parameter Value Selectable parameter Default
0 for OCR
to
5 for OCR
B’xxxxx000’
to
B’xxxxx101’
Brightest
Darkest
IPC-2D
6 for
Image
7 for
Image
B’xxxxx110’
B’xxxxx111’
makes bright image to dark
makes dark image to bright
6 for
image
IPC-3D 0
to
4
to
7
B’xxxxx000’
to
B’xxxxx100’
to
B’xxxxx111’
Decrease the noise
Normal
makes image sharp but increases
noise
4