Genius VividPro II, Руководство пользователя

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Chapter IV. The TWAIN Interface
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colors in the prescanned image you see in the Prescan
Area will be exactly the same as the colors in the final
scanned image in the image-editing program.
When the monitor gamma in the TWAIN program
and all your image-editing applications are the same,
you will only need to adjust the Image Gamma to
change the color brightness for scanned images in all
applications. Changing the image gamma value (by
clicking on the Gamma tab at the top right of the
Advanced window) allows you to change the
brightness of the colors in the image itself , and
keeping all monitor gamma values in your programs
consistent ensures that colors will always be displayed
in the same way.
Auto Density
Checking this box automatically adjusts the
Histogram to make the scanned image clearer. It does
this by increasing the difference between color tones.
Auto Density defines the lightest and darkest
pixels in each channel as white and black and then
redistributes the intermediate pixel values
proportionately.
In general, the Auto Density feature gives good
results when a simple contrast adjustment is needed to
enhance an image with an average distribution of pixel
values; however, this feature does not provide the
more precise control that can be achieved by adjusting
the Histogram controls manually.
Inverse
When inverse is checked the colors of an entire
image will become reversed. A black and white image
will look like a photo negative. A color image reverses
using additive colors.
Descreen
Descreen applies filtering to images that contain
moiré patterns (or herringbone). A moiré pattern is
created from scanning pictures in magazines, or
printed material that use color dithering. The descreen
filter is not needed when scanning original
photographs or black and white images and text, but is