User`s guide

Advanced Properties
VirtualReScan (VRS) User’s Guide
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In some cases, you may want to remove all instances of one color, such as the
background color, on a document in order to make the necessary data more accessible
to OCR engines, etc. One method to effectively “erase” this unwanted color during
scanning is to use color dropout. If you select a color to “drop out,” your scanner will
ignore that color, but capture everything else.
The Front Side Dropout Color and Back Side Dropout Color groups provide the
following dropout color choices: None, Red, Green, or Blue. The default is None. If a
scanner supports duplex, you can select different dropout colors for the front and for
the back side.
Note The back side options for color dropout are disabled for some scanners that
support single-sided scanning only.
JPEG (Joint Photographic Expert Group) is a standardized image format designed to
compress color and grayscale images. In the JPEG Compression group of the Color
panel, you can activate JPEG compression via the Enabled check box. When the
Enabled check box is selected, you may then select an image quality level of Good
(65), Better (80), Best (95), or Custom.
When the Custom image quality level option is selected, both a YUV value and a
Custom JPEG Compression Value may be set. The Custom value has a range of 1 to
100, with a default of 65. As a very general example, setting the JPEG Compression
Value at 100 would probably compress the image so lightly that it would be near its
original size; a JPEG Compression Value of 10, however, could result in major data
loss.
You may type a custom quality JPEG Compression Value into the text box provided,
or use the up and down arrows to select a value. Because results from the Custom
JPEG Compression value cannot be predicted with certainty, use this setting with
caution. The key is to achieve an agreeable balance between better performance
(through optimum compression) and quality of the images. Avoid compression that
speeds up scanning yet loses necessary data.
YUV, a color-encoding scheme involving luminance (frame and field brightness or
“Y”) and chrominance (color information or “UV”), may be selected if desired from
the drop-down list. The choices for YUV may vary by scanner. When the JPEG
Compression Enabled check box is clear, the Quality, YUV, and quality Value choices
are disabled.