Hierarchical multidimensional lookup table generation

A system for generating a hierarchical rendering lookup table for implementing a color transformation within a color imaging system, said system comprising:

• a memory and a storage device;
• and
• a processor in communication with said storage device and said memory, said processor executing machine readable instructions for performing the method of:
• receiving a coarse look-up table (LUT) and a gamut of a color device, said coarse LUT comprising a plurality of coarse LUT nodes arrayed on a plurality of coarse levels on a structured coarse grid;
• identifying at least one coarse LUT sub-cube within said structured coarse grid that is bisected by a boundary surface of said gamut;
• associating at least one fine LUT containing fine LUT nodes that lay on a fine structured grid within each of said identified at least one coarse LUT sub-cube, wherein values of each associated fine LUT node are determined such that a colorimetric-to-device function is continuous across an interface between said structured fine grid and said structured coarse grid;
• determining output values for each coarse and fine LUT node of each of said identified at least one coarse LUT sub-cube;
• and
• generating a hierarchical LUT from said identified at least one coarse LUT sub-cube and said associated fine LUT nodes.

A computer implemented method for generating a hierarchical rendering lookup table for implementing a color transformation within a color imaging system, the method comprising:

• receiving a coarse look-up table (LUT) and a gamut of a color device, said coarse LUT comprising a plurality of coarse LUT nodes arrayed on a plurality of coarse levels on a structured coarse grid;
• identifying coarse LUT sub-cubes within said structured coarse grid that are bisected by a boundary surface of said gamut;
• associating a fine LUT containing fine LUT nodes that lay on a fine structured grid within each respective identified coarse LUT sub-cube, wherein values of each associated fine LUT node are determined such that a colorimetric-to-device function is continuous across an interface between said structured fine grid and said structured coarse grid;
• determining output values for all coarse and fine LUT nodes of said identified coarse LUT sub-cubes wherein values of each fine LUT node are determined such that a colorimetric-to-device function is continuous across an interface between said structured fine grid and said structured coarse grid;
• and
• generating a hierarchical LUT from said identified coarse LUT sub-cubes and said associated fine LUT nodes.