The Colormap Window
The colormap window displays the current (or another explicitly selected) colormap and allows to manipulate it. The colormap is calculated by interpolation among explicitly maintained interpolation points. Each colormap has at least two such points: the outermost indices.
When the mouse is moved over the main window a vertical dashed line indicates the colormap index of the actual pixel of the image.
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The Interpolation Points
An interpolation point can be created for every index of the colormap just by clicking at the appropriate column. They are marked by small black and white rectangles. If the mouse is over such an interpolation point a cross hair mouse pointer is shown. Clicking on an interpolation point opens a color maintenance dialog. Moving the mouse while keeping the mouse button pressed moves the interpolation point. It is not possible to move it over adjacent ones.
If the control key is pressed while an interpolation point is selected, it will be deleted.
The Color Dialog
The color dialog can be used to manipulate the color value of an interpolation point. While changing the color the colormap interpolation and the image shown in the main window are automatically adapted on-the-fly. There are several flavors to change the color, for example RGB and HSB maintenance.
A small slider bar in the color sample area can be used to move the interpolation point between the borders of the adjacent interpolation points.