FULL-COLOR TO A SPOT-COLOR IMAGE CONVERTER

A method for transforming an image, containing an arbitrary number of colors from a full color process printing mode to a spot color printing mode while preserving the user's intended color usage as much as possible. The method is contained in a utility and referred to as “Spot Color Transformation” (SCT). The SCT utility provides a user the ability to transform an image generated by a computer program module, such as a desktop publishing computer program module, from a full color mode into a spot color mode. The SCT utility operates on an object-by-object basis to map objects within an image to one of several partitions: a black partition and a color partition. The SCT utility maps each object that has an associated color that is substantially black or a tint of black to the black partition. Next, the SCT utility converts the colors of unmapped objects to a tint of the spot color based on the luminance value of the particular color relative to the lowest luminance value found in the image. Finally each converted object and its corresponding tint of the spot color are mapped to the spot color partition. The partitions are then used to print copies of the image.