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Chapter 10: The Palette Editor

The palette editor is a tool to change image colors. The color palette displays the color values for the current foreground and background colors. Changing the palette will change the color of the image. The palette editor uses the RGB (red, green and blue) model to store image colors. Using this model, each of the 256 colors is stored as some blend of varying quantities of red, green, and blue. Any or all of the three components can be changed for any pixel, changing the color displayed for that pixel.
10.1 Palette Editor Window
10.2 Palette Menu
10.3 Palette Options
10.4 Saving a New Color Palette


10.1 Palette Editor Window

To start the palette editor, you can either select New Palette from the Palette menu in the image window, or press the Palette button in the animation window. Either action will open the palette editor window.

The palette editor window provides several features for palette control. The Undo button, on the left, can be used at any point to revert to the original palette settings. Four color panels appear in the middle of the window: the edited color panel, the red color panel, the green color panel, and the blue color panel. To the right are several control and selection buttons: flip, fiddle, random, point, and line.


Figure 10.1 The palette editor

10.2 Palette Menu

The palette editor provides several predefined color scales. You can select a predefined color scale from the palette menu in the palette editor and modify it to make the best color palette for the image.

GrayScale
GrayScale-Banded
GrayScale-Inverted
Rainbow
Rainbow-Banded
Rainbow-Inverted
Rainbow-Striped
Grayscale accepts the grayscale built-in palette for the current image.
Grayscale-banded is another type of grayscale palette.
Rainbow is a linear hue ramp from purple to red at maximum saturation and value.
Rainbow-banded is another type of rainbow palette.

10.3 Palette Options

Each color panel has a Point and a Line button. The default setting is Point, allowing you to move the cursor on the panel and change the color table point by point. Line allows you to change the color table line by line. The following is an example of changing color by line and by point.


Figure 10.2 Color panel
Undo recovers the palette table from all the changes and restores the original color values.
Fiddle is used to squeeze or expand the color table. To squeeze or expand the color table, first select Fiddle, then move the cursor up or down on the color panels.
Flip flips the color table. It replaces the first value in the selected interval with the last value for each displayed component, second value with the next to last, and so on.
Random randomly sets the palette values. To select random palette values, first make sure that Fiddle is unselected, and then select Random.

10.4 Saving a New Color Palette

To save a new color palette and attach it to an image, select Set Palette from the image window Palette menu before closing the palette editor.


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