Heuristic analysis of von Kries color constancy

Worthey, James A.; Brill, Michael H.

doi:10.1364/josaa.3.001708

Cited by 123 publications

(54 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At this ∆λ, there is minimal receptor overlap ( Fig. 1), which consistent with existing theory, would improve independent spectral sampling (34). However, this tuning difference (∆λ = 260 nm) requires a spectral separation involving a longwavelength sensitivity not ever observed in bees (35), and the Tc values at which resolution is maximum are not the most frequent values observed in diurnal conditions (Fig.…”

Section: Significancesupporting

confidence: 80%

Improved color constancy in honey bees enabled by parallel visual projections from dorsal ocelli

Garcia

Hung

Greentree

et al. 2017

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

How can a pollinator, like the honey bee, perceive the same colors on visited flowers, despite continuous and rapid changes in ambient illumination and background color? A hundred years ago, von Kries proposed an elegant solution to this problem, color constancy, which is currently incorporated in many imaging and technological applications. However, empirical evidence on how this method can operate on animal brains remains tenuous. Our mathematical modeling proposes that the observed spectral tuning of simple ocellar photoreceptors in the honey bee allows for the necessary input for an optimal color constancy solution to most natural light environments. The model is fully supported by our detailed description of a neural pathway allowing for the integration of signals originating from the ocellar photoreceptors to the information processing regions in the bee brain. These findings reveal a neural implementation to the classic color constancy problem that can be easily translated into artificial color imaging systems.daylight | insect | vision | neuron tracing | von Kries C olor constancy allows natural and artificial visual systems to solve the challenge of maintaining the color sensation of an object despite changes in the illumination. Color constancy requires the visual system to discount an unknown illumination function, when the only available information to a sensor may be the total response of the different photoreceptors present in the visual system (1).Color constancy by chromatic adaptation is classically modeled by assuming a set of scalar coefficients that adjust the sensitivity of the different sensors responsible for color vision depending on the particular ambient light conditions (2, 3). The chromatic effect produced by variation of the spectral power distribution (SPD) of daylight is explained by differences in the ratio of long to short wavelengths observed at different conditions of daylight (4). This variability is constrained, potentially making possible the recovery of SPD from a limited number of sensor responses and simplifying color constancy solutions (5). Indeed, it is possible to reconstruct the entire SPD for different phases of daylight with just two functions summarizing daylight variability at short (<550 nm) and long (>550 nm) wavelengths (6). However, visual targets often present complex shapes and textures and are illuminated by variable intensity, spectrally mixed illumination, potentially requiring the use of contextual information for achieving color constancy (7,8). Chromatic adaptation is thus thought unlikely to be the sole mechanism enabling constancy (8, 9), and different cortical or other neural processing mechanisms seem important for reliable color vision (10, 11). Considering human vision, color processing involves multistage neural representations from V1 to V4 and the frontal cortex, and although V4 neurons seem critical for automatic color constancy operations (11-14), subsequent neural processing stages have been implicated (15).Although this evidence suggests ...

show abstract

Section: Significancesupporting

confidence: 80%

Improved color constancy in honey bees enabled by parallel visual projections from dorsal ocelli

Garcia

Hung

Greentree

et al. 2017

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…Detailed analyses of the way this result depends on the relationships between reflectance spectra, illuminant spectra and receptoral sensitivities are provided by several authors (e.g. Maloney 1986;Worthey & Brill 1986;Dannemiller 1993;Zaidi 2001). But their conclusions differ.…”

Section: (Iv) Coding Colour Relations By Ratiosmentioning

confidence: 99%

Sensory, computational and cognitive components of human colour constancy

Smithson

2005

Phil. Trans. R. Soc. B

184

139

View full text Add to dashboard Cite

When the illumination on a scene changes, so do the visual signals elicited by that scene. In spite of these changes, the objects within a scene tend to remain constant in their apparent colour. We start this review by discussing the psychophysical procedures that have been used to quantify colour constancy. The transformation imposed on the visual signals by a change in illumination dictates what the visual system must 'undo' to achieve constancy. The problem is mathematically underdetermined, and can be solved only by exploiting regularities of the visual world. The last decade has seen a substantial increase in our knowledge of such regularities as technical advances have made it possible to make empirical measurements of large numbers of environmental scenes and illuminants. This review provides a taxonomy of models of human colour constancy based first on the assumptions they make about how the inverse transformation might be simplified, and second, on how the parameters of the inverse transformation might be set by elements of a complex scene. Candidate algorithms for human colour constancy are represented graphically and pictorially, and the availability and utility of an accurate estimate of the illuminant is discussed. Throughout this review, we consider both the information that is, in principle, available and empirical assessments of what information the visual system actually uses. In the final section we discuss where in our visual systems these computations might be implemented.

show abstract

“…Moreover, even in daylight it could be difficult for dichromatic animals to recognize visual objects by their surface colour under changing lighting conditions. As follows from theoretical considerations, low-dimensional colour vision exhibits a high degree of colour metamerism, thwarting colour constancy under changes in the spectral composition of the illuminant [4][5][6]. This apparently makes the assumption of the significance of colour recognition in dogs (and in dichromatic mammals in general) even less feasible.…”

Section: Introductionmentioning

confidence: 99%

Colour cues proved to be more informative for dogs than brightness

2013

View full text Add to dashboard Cite

The results of early studies on colour vision in dogs led to the conclusion that chromatic cues are unimportant for dogs during their normal activities. Nevertheless, the canine retina possesses two cone types which provide at least the potential for colour vision. Recently, experiments controlling for the brightness information in visual stimuli demonstrated that dogs have the ability to perform chromatic discrimination. Here, we show that for eight previously untrained dogs colour proved to be more informative than brightness when choosing between visual stimuli differing both in brightness and chromaticity. Although brightness could have been used by the dogs in our experiments (unlike previous studies), it was not. Our results demonstrate that under natural photopic lighting conditions colour information may be predominant even for animals that possess only two spectral types of cone photoreceptors.

show abstract

Heuristic analysis of von Kries color constancy

Cited by 123 publications

References 9 publications

Improved color constancy in honey bees enabled by parallel visual projections from dorsal ocelli

Improved color constancy in honey bees enabled by parallel visual projections from dorsal ocelli

Sensory, computational and cognitive components of human colour constancy

Colour cues proved to be more informative for dogs than brightness

Contact Info

Product

Resources

About