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4.12 Noise Removal
This image filter reduces the noise (black spots) of images.
Noise is caused by particles of carbon deposited from the printing by the copier or
fax machine and by dirt and other foreign matter on the documents when they are
scanned by the scanner.
When noise is removed from the text areas, the dots over the letters “i” and “j” and
other information may also be removed in error. In cases like this, select a value
larger than the gap between the dots and other parts for the minimum gap setting.
When the Noise Removal and Crop functions are applied to the same image, better
results are yielded when Noise Removal is applied first.
In order to obtain the optimum image quality and speed, it is recommended that the
settings of the image filters be adjusted while scanning an actual document.
[Noise Removal Properties] dialog box
Max Height
The maximum height of what is to be considered as noise is set here. Inches,
millimeters or points can be used as the unit for the setting. Input “mm” or “pt”
after the number, respectively. A fraction such as 1/100 can also be specified
as the number.
Max Width
The maximum width of what is to be considered as noise is set here. Inches,
millimeters or points can be used as the unit for the setting. Input “mm” or “pt”
after the number, respectively. A fraction such as 1/100 can also be specified
as the number.
Before Noise Removal
After Noise Removal
