Abstract: In a windows environment, a plurality of computer program applications use a common look-up table to allocate colors. When the common look-up table is full, a mechanism must be provided to determine which colors will be stored in the common look-up table. Several alternatives exist; the order of the alternatives can be specified by the user or application program. A first alternative will attempt to allocate colors in the common look-up table with the true image colors called for by the program. A second alternative uses a reduced set (reduced number) of image colors so that they will fit in the common look-up table. The image colors are regenerated from the reduced set through a dithering or error diffusion algorithm. A third alternative is to find the color in the common look-up table which is mathematically closest to the image color. If these alternatives are not used, a new look-up table can be created.