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Volume: 23 | Article ID: art00057_2
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Evaluating the Image Permanence of Full Tonal Scale Human Skintone Colors in Photographs Using the CIELAB Colorimetry Based WIR i-Star “Retained Image Appearance” Metric
Henry Wilhelm
Dmitriy Shklyarov
  DOI :  10.2352/ISSN.2169-4451.2007.23.1.art00057_2  Published Online :  January 2007
Abstract

People are the principal subjects in the great majority of consumer photographs and the rich and vibrant reproduction of skintones in prints is an essential requirement for professional portrait and wedding photographers. Current ISO and WIR methods for the evaluation of image permanence in color prints only take into account fading in cyan, magenta, and yellow patches, as well as fading and color imbalance changes in neutral scale patches (at a single density of 1.0 with ISO 18909 and at two density points, 0.6 and 1.0 with WIR). The ISO and WIR methods do not directly address fading and color balance changes in human skintones. This shortcoming is particularly significant for prints made with complex inkjet inksets that, in addition to cyan, magenta, and yellow inks, may contain dilute cyan and magenta inks, as well as red, green, blue, orange, or other ink colors and multi-level black/gray inks. WIR i-Star, a CIELAB colorimetry-based, full tonal scale “retained image appearance” metric, provides a method to evaluate the permanence of human skintone colors, neutrals and nearneutrals, as well as a full range of the printable colors in sRGB or other color spaces over the full tonal scale found in photographs. The WIR i-Star metric can be used to evaluate changes in colors as well as changes in both localized and overall image contrast.

Journal Title : NIP & Digital Fabrication Conference
Publisher Name : Society of Imaging Science and Technology
Publisher Location : 7003 Kilworth Lane, Springfield, VA 22151, USA
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 DOI 10.2352/ISSN.2169-4451.2007.23.1.art00057_2
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Henry Wilhelm, Dmitriy Shklyarov, "Evaluating the Image Permanence of Full Tonal Scale Human Skintone Colors in Photographs Using the CIELAB Colorimetry Based WIR i-Star “Retained Image Appearance” Metric"  in Proc. IS&T Int'l Conf. on Digital Printing Technologies and Digital Fabrication (NIP23),  2007,  pp 743 - 748,  https://doi.org/10.2352/ISSN.2169-4451.2007.23.1.art00057_2

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Copyright © Society for Imaging Science and Technology 2007
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NIP & Digital Fabrication Conference
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Society of Imaging Science and Technology
7003 Kilworth Lane, Springfield, VA 22151, USA
2169-4451(20070101)2007:2L.743;1-
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Articles
Evaluating the Image Permanence of Full Tonal Scale Human Skintone Colors in Photographs Using the CIELAB Colorimetry Based WIR i-Star “Retained Image Appearance” Metric
WilhelmHenry
ShklyarovDmitriy
01012007
2007
2
743
748
2007
People are the principal subjects in the great majority of consumer photographs and the rich and vibrant reproduction of skintones in prints is an essential requirement for professional portrait and wedding photographers. Current ISO and WIR methods for the evaluation of image permanence in color prints only take into account fading in cyan, magenta, and yellow patches, as well as fading and color imbalance changes in neutral scale patches (at a single density of 1.0 with ISO 18909 and at two density points, 0.6 and 1.0 with WIR). The ISO and WIR methods do not directly address fading and color balance changes in human skintones. This shortcoming is particularly significant for prints made with complex inkjet inksets that, in addition to cyan, magenta, and yellow inks, may contain dilute cyan and magenta inks, as well as red, green, blue, orange, or other ink colors and multi-level black/gray inks. WIR i-Star, a CIELAB colorimetry-based, full tonal scale “retained image appearance” metric, provides a method to evaluate the permanence of human skintone colors, neutrals and nearneutrals, as well as a full range of the printable colors in sRGB or other color spaces over the full tonal scale found in photographs. The WIR i-Star metric can be used to evaluate changes in colors as well as changes in both localized and overall image contrast.