lut = createObject("java","java.awt.image.ShortLookupTable").init(0, posterize); op = createObject("java","java.awt.image.LookupOp"); posterizedImage = createObject("java","java.awt.image.BufferedImage").init(img.getWidth(), img.getHeight(), img.getType()); op.init(lut, javacast("null","")); op.filter(img, posterizedImage); return posterizedImage;