The Color Exchange filter performs color replacement on user-defined colors. By selecting a "From color" from the image window within the Color Exchange dialog window and then selecting an appropriate "To Color", the selected color will be replaced.
Color Exchange Settings
This filter provides a preview window that can also be used as a color selection window. Simply click with Button1inside the preview window to change the From Color to whatever color the mouse cursor is over at the time.
At the top of this section is a clickable color well. This color well launches the color selection dialog which allows the selection of a source color range.
There are two groups of three sliders available that alter the way this filter operates.
Red: This slider alters the amount of red color information used for the From Color color well.
Green: This slider alters the amount of green color information used for the From Color color well.
Blue: This slider alters the amount of blue color information that is used for the From Color color well.
Red Threshold: This slider changes the aggressiveness for the amount of red used in the color selection.
Green Threshold: This slider changes the aggressiveness for the amount of green used in the color selection.
Blue Threshold: This slider changes the aggressiveness for the amount of blue used in the color selection.
The Lock Thresholds checkbox forces all threshold sliders to work in unison, providing balanced selection aggression across all three color ranges.
The To Color section provides the mapping for the color destination. All colors that are selected using the options available in the From Color section will be mapped to the color selected here.
The color well can be clicked to launch the color selection dialog.
If a more manual method of color selection is required, there are three sliders available here. Each of these sliders represents one of the three primary colors that are available in the context of the image.