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Performance of a color-difference formula based on OSA-UCS space using small-medium color differences.

Rafael Huertas·Manuel Melgosa·Claudio Oleari
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Abstract

An investigation of the color metrics and the complexity of the CIEDE2000 formula shows that CIELAB space is inadequate to represent small-medium color differences. The OSA-UCS (Uniform Color Space) Committee has shown that no space with uniform scale for large color differences exists. Therefore the practical way for color-difference specification is a color-difference formula in a nonuniform space. First, the BFD (Bradford University) ellipses are considered in the OSA-UCS space, and their very high regularity suggests a new and very simple color-difference formula at constant luminance. Then the COM (combined) data set used for the development of the CIEDE2000 formula is considered in the OSA-UCS space, and the color-difference formula is extended to sample pairs with a different luminance factor. The value of the performance factor PF/3 for the proposed OSA-UCS-based formula shows that the formula performs like the more complex CIEDE2000 formula for small-medium color differences.

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AlgorithmsColorColorimetryDifferential ThresholdEuropeGuidelines as TopicReference StandardsReproducibility of ResultsSensitivity and SpecificityJournal Article

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Rafael Huertas, Manuel Melgosa, Claudio Oleari. 2006. Performance of a color-difference formula based on OSA-UCS space using small-medium color differences.. https://doi.org/10.1364/josaa.23.002077

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