Canon DR-9080C Service Manual page 59

6. Binarizing
Image binarizing is described below. For the
"Advanced text enhancement," refer to the
section entitled "IMAGE PROCESSING IN THE
COMPUTER."
1) Simple Binarizing
Binary image data can only express picture
elements as either "black" or "white."
In order to separate the picture elements into
black and white, signals corresponding to the
image density of the document must be cut off at
a certain level, so that anything above that level is
judged as "white" and anything below as "black."
This is called simple binarizing . This is useful for
text documents. Simple binarizing for this
machine is called "Black and White" mode.
The level at which picture elements are to be
divided into white or black is called the "slice
level" (or threshold value).
1 picture element
White 255
160
128
96
Black 0
Document
Output
Fig. 2-511
COPYRIGHT © 2003 CANON ELECTRONICS INC.
White
Slice level
Black
CANON DR-6080/9080C REV.0 SEPT. 2003
CHAPTER 2 FUNCTIONS & OPERATION
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