CIE Division 8 - TC8-03: Survey of Gamut Mapping Papers

Buckley (1978)


This thesis compared gamut compression of color separations with gamut compression in U*V*W* color space (the precursor of CIELUV). Non-parametric tests were used to evaluate the results of subjective comparisons: which approach was preferred and which was considered closest to the original. The U*V*W* gamut-compression algorithm did a linear lightness compression, followed by a chroma compression along lines of constant hue in U*V*W* space. All chroma values were compressed linearly, as suggested by Evan's Consistency Principle and Bartleson's Relativity Principle. The gamut compression was image dependent and in the case of U*V*W* compression, modeled the hardcopy output gamut used in the experiments as an irregular polyhedron. Gamut compression in U*V*W* resulted in reproductions that were either preferred or judged closer to the original. Lightness sharpening was added in a post-processing step to increase the sharpness and the apparent contrast and chroma of the gamut-compressed images.
 


Last updated: 19 January 2000 by Jan Morovic