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3.  Image content related dialogs

3.1.  Colors dialog

Revision History
Revision $Revision: 1.37 $ 2006-02-28 j.h

Figure 9.22.  Colors dialog

Colors dialog

The Channel dialog lets you manage and pick up new colors. It is divided into five separate parts: GIMP, CMYK, Triangle, Watercolor and Scales. You can use the eyedropper, which is the last button of the dialog, to pick up a color anywhere on your screen.

3.1.1.  Activate Dialog

The dialog can be called in the following ways :

  • from the toolbox-menu: File->Dialogs->Colors

  • from the toolbox: click on the current Foreground or Background color.

  • from the image-menu: Dialogs->Colors

  • from an other dialog-menu: Add Tab->Colors

3.1.2.  Using the dialog

The GIMP Selector

With the GIMP Color Selector, you select a color by clicking on a one-dimensional strip located at the right edge, and then in a two-dimensional area located on the left. The one-dimensional strip can encode any of the color parameters H, S, V, R, G, or B, as determined by which of the adjoining buttons is pressed. The two-dimensional area then encodes the two complementary color parameters.


You get to this selector by clicking on the printer icon. The CMYK view gives you the possibility to manage colors from the CMYK color model.


The Triangle selector is made up of a chromatic circle that allows to select Hue by click-and-drag a small circle and of a triangle that has also a small circle to vary intuitively Saturation and Value.


This color selector is symbolized by a brush. The function mode of the selector is a little different than those of the models presented so far. The principle consists of changing the current foreground color by clicking into into the rectangular palette. If the current foreground color is for example white, then this is reddish toned by one clicking into the red color area. Repeated clicking strengthens the effect. With the sliding control, which is right apart from the color palette, you can trim the color quantity by which with every mouse click, it takes up. The further the sliding control is above, the more color taken up per click.


This Scales exists only in the color selector you get from the file menu of the Tool-Box or from the Dialogs menu in the image menu bar.

This selector displays a global view of R, G, B channels and H, S, V values, placed in sliders.

Color picker

This color picker exists only in the color selector you get from the file menu of the Tool-Box or from the Dialogs menu in the image menu bar.

The color picker has a completely different behaviour, than the color picker tool. Instead of picking the colors from the active image, you're able to pick colors from the entire screen.

As described above, the color selection tool started from the toolbox file menu and the image menu is different from the color selection tool started in any other way. In the first tool, in the lower part of the dialog, is showed the current foreground and background colour. One of the two colors is in each case, recognizable actively from a thin grey framework, which surrounds the active color box. In order to activate a color box, you can simply click on the desired box. All the modifications you do with the color selectors, apply to the active color box.

Right up you find a symbol, consisting of two arrows, with which you can exchange the foreground and background colour. At the bottom left of the dialog, just below the foreground color block, you find a switching surface with two small, one black and the other white, partially overlapping squares. If you click on these, the front and background colour are put back to black and white respectively.

  Published under the terms of the GNU General Public License Design by Interspire