The Effect of Global Contrast Distribution on Colour Appearance

A perceptual study was conducted to enhance colour image quality in terms of naturalness and preference using perceptual scales of saturation and vividness. Saturation scale has been extensively used for this purpose while vividness has been little used. We used perceptual scales of a recently developed colour appearance model based on Jzazbz uniform colour space. A two-fold aim of the study was (i) to test performance of recently developed perceptual scales of saturation and vividness compared with previously used hypothetical models and (ii) to compare performance and chose one of saturation and vividness scales for colour image enhancement in future. Test images were first transformed to Jzazbz colour space and their saturation and vividness were then decreased or increased to obtain 6 different variants of the image. Categorical judgment method was used to judge preference and naturalness of different variants of the test images and results are reported.

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Measuring colour appearance of red wines

Food Quality and Preference ◽

10.1016/j.foodqual.2007.01.013 ◽

2007 ◽

Vol 18 (6) ◽

pp. 862-871 ◽

Cited By ~ 34

Author(s):

Maria Lourdes Gonzalez-Miret Martin ◽

Wei Ji ◽

Ronnier Luo ◽

John Hutchings ◽

Francisco J. Heredia

Keyword(s):

Red Wines ◽

Colour Appearance

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Food colour appearance Judged using images on a computer display

The Imaging Science Journal ◽

10.1080/13682199.2002.11784389 ◽

2002 ◽

Vol 50 (1) ◽

pp. 23-36 ◽

Cited By ~ 7

Author(s):

M R Pointer ◽

G G Attridge ◽

R E Jacobson

Keyword(s):

Food Colour ◽

Colour Appearance

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Testing Colour Appearance Model Based UCS Using HDR, WCG and COMBVD Datasets

Color and Imaging Conference ◽

10.2352/issn.2169-2629.2021.29.381 ◽

2021 ◽

Vol 2021 (29) ◽

pp. 381-386

Author(s):

Xu Qiang ◽

Muhammad Safdar ◽

Ming Ronnier Luo

Keyword(s):

Correlation Coefficient ◽

Power Factor ◽

Marked Improvement ◽

Appearance Model ◽

Colour Difference ◽

Similar Performance ◽

Model Based ◽

Test Models ◽

Appearance Models ◽

Colour Appearance

Two colour appearance models based UCSs, CAM16-UCS and ZCAM-QMh, were tested using HDR, WCG and COMBVD datasets. As a comparison, two widely used UCSs, CIELAB and ICTCP, were tested. Metrics of the STRESS and correlation coefficient between predicted colour differences and visual differences, together with local and global uniformity based on their chromatic discrimination ellipses, were applied to test models' performance. The two UCSs give similar performance. The luminance parametric factor kL, and power factor γ, were introduced to optimize colour-difference models. Factors kL and γ of 0.75 and 0.5, gave marked improvement to predict the HDR dataset. Factor kL of 0.3 gave significant improvement in the test of WCG dataset. In the test of COMBVD dataset, optimization provide very limited improvement.

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