The following options are provided:
Threshold: The threshold for the coring. Any pixel below this threshold is set to the coring value (usually black).
Core to threshold: Sometimes the coring will produce an abrupt change from dark grey to black that can be noticable. If core is done to the threshold value, this effect should disappear at the expense of making the "pure black" parts dark grey.
Core to green: This temporarily sets the coring value to green. This facilitates adjusting the coring threshold as the cored pixels become immediately visible.
Brightness slider: The slider will adjust the bightness for the preview (same reason as stated above).
Version 1.0 [Source code]
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