7 Binarization and Color Separation
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Binarization
Binarization creates a new monochrome image of a specified color, which is placed
on the specified layer. Using the specific criterion the program defines which pixels
of the original (color or grayscale) image should become black (foreground pixels),
and which ones should become white (background pixels), and then generates a
monochrome image and places it on a new raster layer. The criterion for division of
pixels into two sets is defined by the selected
binarization method
and its
parameters (threshold values or a set of color range).
Binarization methods
To convert color and grayscale images to monochrome, various conversion
algorithms are used, called
binarization methods
. It is recommended that you
choose a conversion method appropriate to the image type.
Threshold by Grey
Threshold by Grey
converts color pixels with brightness values above the specified
level to background dots, and it converts pixels below this level to image dots.
This method may be used for converting both color and grayscale images. When
converting a grayscale image, WiseImage uses its grey levels. When converting a
color image, the grey levels are defined by the brightness value of color pixels.
Threshold by RGB
When using
Threshold by RGB
, you should define three threshold levels for the
Red, Green, and Blue components. WiseImage converts color dots with Red, Green
and Blue values below the appropriate threshold levels to black dots (image dots) of
the monochrome image.
Range by Grey
Range by Grey
allows you to convert color dots with any brightness value to image
dots. Using this method, you first specify several basic grey levels. These levels are
used as midpoints for
ranges
. For each of the specified levels, you can define a
range half-length
. A range half-length is a number of grey levels below and above
the specified grey level.
Range by Grey
converts pixels that have grey values within all specified ranges to
foreground dots. Other pixels are converted to background dots.
This method may also be used for converting color and grayscale images. Grey
levels for color dots are calculated as described in
Threshold by Grey
.
