ISSN:0361-2317    

DOI:10.1002/col.5080140602

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

ISSN:0361-2317    

DOI:10.1002/col.5080140603

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

ISSN:0361-2317    

DOI:10.1002/col.5080140604

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

ISSN:0361-2317    

DOI:10.1002/col.5080140605

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractThe perceptual effects that inform a series of paintings are analyzed and described using the tools of the visual psychologist and psychophysiologist.

ISSN:0361-2317    

DOI:10.1002/col.5080140606

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractThe hues of foveal monochromatic increments on concentric white backgrounds were measured as a function of the background retinal illuminance. For each background illuminance tested, the illuminance of the test spot was set 0.6 log unit above its increment threshold, and relative percentages of redness, yellowness, greenness, and blueness were estimated. The percentage of whiteness was also estimated in a separate judgement. At low background illuminances, the spectrum is dominated by blue at short and middle wavelengths and by red at long wavelengths. Higher background illuminances are marked by dramatic growth of yellow and green at middle wavelengths and red at short wavelengths. At still higher photopic levels, the pattern reverts back toward that seen at low background illuminances. The hue patterns at low and high adapting levels are characteristic of tritanopic vision, and are attributable to selective sensitivity losses in chromatic neural pathways that process short‐wavelength‐sensitive (S) cone responses. These results reinforce previous evidence that S cone activity produces a reddish purple hue at short wavelengths and (indirectly) a yellow hue at middle and long wavelengths, and that middle‐wavelength‐sensitive cone activity produces a slightly greeni

ISSN:0361-2317    

DOI:10.1002/col.5080140607

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractChromatic adaptation can significantly alter the color appearance of a light. We review measurements of changes in appearance caused by chromatic backgrounds and surrounds. Effects of long‐, middle‐ and short‐wavelength adapting lights are assessed by having observers adjust the physical light in a test patch to maintain a constant perceptual criterion: a test that appears neither reddish nor greenish. A variety of spatial and temporal stimulus configurations also is considered. An integrated account of the measurements is provided by the two‐process theory of chromatic adaptation, originally proposed by Hurvich and Jameson in 1958, which specifies an adapting light alters receptoral sensitivities and, simultaneously, contributes an additive increment to opponent chromatic re

ISSN:0361-2317    

DOI:10.1002/col.5080140608

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractUnique hue loci of red, yellow, green, and blue were obtained for lights of 0.5 and 2 cd. m‐2from five normal color vision subjects. Most loci curved on the chromaticity diagram. This result excludes linear equations of colormatching functions as candidates for spectral sensitivity functions of opponent color systems, (r/g)λ and (y/b)λ. The chromatic valence curves of two opponent color systems obtained by the so‐called cancellation experiment were analyzed in relation to the unique hue loci and it was shown that the appearance of the valence curves can be manipulated at will by choosing the cancellation light at various points on the chromaticity diagram. A similar manipulation was also demonstrated for the additivity property of chromatic valence and it was made clear that no unique solution is obtai

ISSN:0361-2317    

DOI:10.1002/col.5080140609

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractWe propose a method, based on finite‐dimensional linear models of reflection and illumination, which allows the transformation of chromatic images into color constant images. This proves to be useful in applications in which either there is no information on the illuminant present in the scene, or when such information is confounded by the existence of inter‐reflections between objects. The method proposed in this paper is aimed at computations taking place beyond the sensory level of vision systems, and may use inputs corrected by sensors (for adaptation). In contrast to previous work, we show that good results can be obtained using a 3‐receptor system and some knowledge about the spectral properties of natural materials and illuminants. In the method developed, an estimate of the illuminant in the scene is computed, which allow the computation of color constant descriptors of the pixel values in the image. In addition, we show a method of computing an estimate to the actual reflectances of the materials in the scence out of the computed color constant descri

ISSN:0361-2317    

DOI:10.1002/col.5080140610

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

ISSN:0361-2317    

DOI:10.1002/col.5080140611

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY