3.6. Map Color Range

3.6. Map Color Range
	3. Color filters

Revision History
Revision $Revision: 1963 $	2007-05-15	ude

3.6.1. Overview

Figure 15.30. Example for the Map Color Range filter

Original image

Filter “Map Color Range” applied

This filter is found in Filters → Colors → Map → Color Range Mapping.

Unlike Exchange filter, Map Color Range maps a defined color range against another defined color range. More precisely, for every image pixel the values of the color channels (red, green, blue) are separately replaced according to a mapping table. This way, the color range may be moved, stretched, compressed, and/or inverted.

	Note
	This mapping does not apply to the specified source color range only. Colors outside this color range are mapped the same way by extrapolating their destination color.

3.6.2. Options

Figure 15.31. Options of the “Map Color Range” filter

Preview

Preview: This Preview displays color changes interactively, before they are applied to Image.

Color Source Range

The two Color Swatch Boxes allow you to define From and To limits of source color range. Default colors are the Foreground and the Background colors of the Toolbox, but, when you click on a box, you call the Gimp Color selector which lets you select other colors.

Note that, when you select a color, you really select three separate color channels.

	Caution
	It's an error if for some channel both source color values are the same (you cannot map a single value to the destination range). Although the filter seems to work and will not display any warning or error message, this will lead to unexpected and probably unwanted results.

Destination Color Range

The two Color Swatch Boxes allow you to define From and To limits of destination color range. When you click on a box, you call the Gimp's Color selector.