Canon DR-9080C Service Manual page 52

CHAPTER 2 FUNCTIONS & OPERATION
3. Image Resolution Conversion
In this mode,
conversion differs according to the image mode.
Thinning-out is available for binary mode,
smoothing is available for grayscale mode, and
either one is selectable for color mode.
The resolution
direction is the same as in the sub-scanning
direction.
The optical resolution
direction) of the reading unit can be switched
between 600 and 300 dpi. Therefore, when 400
dpi is selected, the resolution is converted from
600 dpi, and when 240 dpi or less is selected, it is
converted from 300 dpi.
300 dpi standard clock
300 dpi image data
200 dpi operating clock
200 dpi image data
2 - 28
the image resolution
in the main-scanning
(main-scanning
1 2
1 2
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a) Thinning-out method
For the main-scanning direction, the image
resolution conversion is executed by thinning out
the standard clocks for image processing. (Refer
to Fig. 2-503)
When converting to 200 dpi, the standard
300 dpi clock is used, with 1 clock pulse
removed from every 3 pulses. When converting
to 240 dpi, 1 clock pulse is removed from every 5
pulses. And, when converting to 400 dpi, the
standard 600 dpi clock is used with 1 clock
removed from every 3 clock pulses.
3 4 5 6 7
3 4 5
Fig. 2-503
8 9 10 11
6 7 8
CANON DR-6080/9080C REV.0 SEPT. 2003