To open your selected photo, go toFile>Openand then navigate to your photo and click theOpenbutton.
If you are happy with the mix of colors throughout your photo you might proceed to the next step.
Under theImagemenu, selectModeand chooseIndexed.
The Indexed Color Conversion dialog box will open.
Change the number in theMaximum Number of Colors, if desired.
The Columns setting will only affect the display of the colors within the palette.
The Interval setting causes a greater gap to be set between each sampled pixel.
Select thePalettestab in the right pane.
The new palette will be displayed as a colormap of the current image.
If you don’t see it, from the Gimp menu, selectWindows>Dockable Dialogs>Palettes.
SelectDuplicate this Paletteat the bottom of the Palettes pane.
Enter a name for the custom palette.
