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Visualizing Visual Adaptation
Published on: April 24, 2017
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Colour constancy failures expected in colourful environments
1Department of Electrical and Electronic Engineering, University of Manchester, Manchester, UK.
Proceedings. Biological Sciences
|January 26, 2022
Summary
Color constancy, the perception of stable surface color under changing light, frequently fails outdoors. This study found that colorful surfaces are more prone to color constancy failures in natural environments.
Area of Science:
- Visual Perception
- Color Science
- Environmental Optics
Background:
- Color constancy is the visual system's ability to perceive surface colors as stable despite variations in illumination.
- Previous laboratory studies suggest color constancy is imperfect.
- The frequency and conditions of color constancy failures in natural outdoor environments remain less understood.
Purpose of the Study:
- To estimate the occurrence of color constancy failures in natural outdoor scenes.
- To investigate the relationship between color constancy failures and the colorimetric properties of surfaces.
Main Methods:
- Computational analysis of 50 hyperspectral reflectance images of outdoor scenes.
- Simulated changes in daylight illumination spectra were applied to the images.
- Calculated changes in perceived color appearance and cone-photoreceptor excitations for a chromatically adapted observer.
Main Results:
- Color constancy failures were observed in a significant portion of surface area across multiple scenes.
- Noticeable color appearance changes affected at least 5% of the surface area in 60% of scenes.
- Failures were more frequent for surfaces with higher chroma and saturation, indicating a correlation with colorfulness.
Conclusions:
- Color constancy is not always perfect in natural outdoor environments.
- Individual surfaces, especially those with high saturation, are susceptible to color constancy failures.
- Surface colorimetric properties, such as chroma, are key factors influencing the degree of constancy failure.
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