Performance of an extended CARISMA gamut mapping model

摘要

Gamut mapping algorithms were tested in a transparency-to-newsprint workflow, using features derived from studies of empirical mappings in high-quality colour reproductions. The experiment compared different methods of determining the achromatic convergence point in simultaneous lightness-chroma compression, and compared linear compression against a non-linear distance -weighted compression. Algorithms whose convergence points were dependent on the lightness and chroma of the cusp and of the colour being mapped performed better than those with fixed convergence points. The models using non-linear compression were strongly preferred over one using linear compression. The gamut mapping algorithm which incorporates non-linear compression and lightness- and chroma-weighted convergence is known as Graphic Arts Media Mapping Algorithm (GAMMA).