Image Scanner User's Manual
¡ Binary scanning / Threshold
Function: A binary composition scanning converts every pixel on the image to either black or white. If the image contains a gray area, the threshold value determines whether the scanner records it as black or white. If the threshold value is high, the scanner records more pixels as black. If the threshold value is low, the scanner records fewer pixels as black.
Usage: Use a binary composition when scanning binary images such as text and line draw- ings; black and white images without any gray areas.
You can select one of following two methods to set the threshold value in binary scanning; manual threshold or dynamic threshold.
Manual threshold
A whole image is binalized using a specified threshold. The threshold can be set between 1 and 255. When scanning a light image, set the threshold higher. When scanning a dark image, set the threshold lower.
Lower threshold | Higher threshold |
Dynamic threshold
The scanned image is binalized with an appropriate threshold as determined by the scanner by using an optional image processing unit.
Dynamic threshold
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