Este plug-in rrefaz as cores da imagem usando cores da paleta ativa que você pode escolher em
+ → .It maps the contents of the specified drawable (layer, selection...) with the active palette. It calculates luminosity of each pixel and replaces the pixel by the palette sample at the corresponding index. A complete black pixel becomes the lowest palette entry, and complete white becomes the highest. Works on both Grayscale and RGB images with or without alpha channel.