Measuring color differences in gonioapparent materials used in the automotive industry

23rd Congress of the International Commission for Optics

Melgosa, M.^1 ; Gómez-Robledo, L.^1 ; Cui, G.^2 ; Li, C.^3 ; Perales, E.^4 ; Martínez-Verdú, F.M.^4 ; Dauser, T.^5

Department of Optics, University of Granada, Granade

18071, Spain^1

University of Wenzhou, Wenzhou

325035, China^2

School of Electronic and Information Engineering, University of Science and Technology Liaoning, Anshan

114051, China^3

Color and Vision Group, Department of Optics, Pharmacology and Anatomy, University of Alicante, Sant Vicent del Raspeig, Alicante

03690, Spain^4

AUDI AG, I/PG-C41, Ingolstadt

85045, Germany^5

关键词: Color appearance models;    Color difference formula;    Experimental conditions;    Gonio apparent materials;    Interobserver variability;    Vision applications;    Visual assessments;    Weighting functions;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/605/1/012006/pdf
DOI  :  10.1088/1742-6596/605/1/012006

来源: IOP

【 摘 要 】

This paper illustrates how to design a visual experiment to measure color differences in gonioapparent materials and how to assess the merits of different advanced color-difference formulas trying to predict the results of such experiment. Successful color-difference formulas are necessary for industrial quality control and artificial color-vision applications. A color- difference formula must be accurate under a wide variety of experimental conditions including the use of challenging materials like, for example, gonioapparent samples. Improving the experimental design in a previous paper [Melgosaet al., Optics Express 22, 3458-3467 (2014)], we have tested 11 advanced color-difference formulas from visual assessments performed by a panel of 11 observers with normal colorvision using a set of 56 nearly achromatic colorpairs of automotive gonioapparent samples. Best predictions of our experimental results were found for the AUDI2000 color-difference formula, followed by color-difference formulas based on the color appearance model CIECAM02. Parameters in the original weighting function for lightness in the AUDI2000 formula were optimized obtaining small improvements. However, a power function from results provided by the AUDI2000 formula considerably improved results, producing values close to the inter-observer variability in our visual experiment. Additional research is required to obtain a modified AUDI2000 color-difference formula significantly better than the current one.