Spectral-reflectance function recovery for improved colour-constancy experiments

• Published in: Displays Vol. 23; no. 5; pp. 213 - 222
• Main Authors: Nieves, Juan L, Pérez-Ocón, F, Hernández-Andrés, J, Romero, J
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier B.V 01.11.2002; Elsevier
• Subjects: Applied sciences; Colour vision; Colour-constancy; Colour-differential thresholds; Display; Electronics; Exact sciences and technology; Reflectances; Separation algorithms; Reflectances; Colour-constancy; Colour-differential thresholds; Colour vision; Separation algorithms; Waveform; Spectral function; Separation capacity; Mental representation; Goodness of fit test; Differential threshold; Color display; Spectral analysis; Information loss; Spectral reflectance; Color matching; Luminance; Experimental result; Color vision; Algorithm performance; Signal spectrum; Cathode ray tubes; Memory effect; Reflectance; Surface reflection
• ISSN: 0141-9382; 1872-7387
• DOI: 10.1016/S0141-9382(02)00040-9

A set of symmetric memory-matching data is presented to analyse some implications of long-term memory factors within classical colour-constancy paradigms and separation algorithms. Using simulated Mondrian-type colour surrounds on a CRT monitor, subjects make a series of colour matches between a test and a matching surface; the surfaces are rendered under the same standard illuminant (equal-energy illuminant). The 16 test surfaces used were categorised into four apparent-hue collections. The analysis of the colour differences show that subjects maintained good mental representations of the surfaces, although a shift in luminance was found. With these results, we investigated how errors in remembering surface colours might be translated into errors in reconstructing surface reflectances. Thus, a description of the remembered surfaces is provided, and the spectral differences are analysed via a goodness-of-fit coefficient (GFC). As it is derived from colour-differential thresholds and GFC values, the analysis of the recalled spectral-reflectance functions shows little loss of information in the observer's task, despite imperfect mathematical recovery of the surfaces. The similarities between test and matching surfaces suggest that colour-constancy algorithms could benefit of memory matches when an illuminant change takes place, and use spectral-tolerance bands defined over the surfaces comprising a scene to improve their implementation.