The Map submenu contains operations that allow you to map the colors of an image to different colors in several ways.
Secção 8.34, “Rearrange Colormap”
Secção 8.35, “Set Colormap”
Secção 8.36, “Alien Map”
Secção 8.37, “Color Exchange”
Secção 8.38, “Rotate Colors”
Secção 8.39, “Gradient Map”
Secção 8.40, “Palette Map”
Secção 8.41, “Sample Colorize”
You can access this command from the main menu through Colors → Map.