Spatial and temporal discrimination ellipsoids in color space.

Three-dimensional discrimination ellipsoids are presented for a number of representative points in color space. These ellipsoids have been obtained not with the conventional split field but with flickering grating patterns. Thus our study extends the well-known results of Brown and MacAdam [J. Opt. Soc. Am. 39, 808-813 (1949)] to cases in which the image is structured in space and time. As expected, we find that the discrimination ellipsoids depend on the spatiotemporal structure of the stimulus. This has potential consequences for color-difference formulas as used in industry and commerce: no single formula will do when it is important to treat patterns with different structure. We present analytical descriptions, based on the Vos-Walraven [Vision Res. 12, 1327-1365 (1972)] line element augmented with spatiotemporal frequency-dependent coefficients that fit our results reasonably well. For coarse gratings (approximately 1 cycle per degree) or slowly modulated fields (approximately 1 Hz) our results prove to be compatible with the results of Brown and MacAdam obtained with a bipartite 2 degree field.

[1]  W. Stiles.  A modified Helmholtz line-element in brightness-colour space , 1946 .

[2]  D. L. Macadam,et al.  Visual sensitivities to combined chromaticity and luminance differences. , 1949, Journal of the Optical Society of America.

[3]  W. R. Brown,et al.  The influence of luminance level on visual sensitivity to color differences. , 1951, Journal of the Optical Society of America.

[4]  J. Robson.  Spatial and Temporal Contrast-Sensitivity Functions of the Visual System , 1966 .

[5]  M. A. Bouman,et al.  Spatiotemporal modulation transfer in the human eye. , 1967, Journal of the Optical Society of America.

[6]  M. A. Bouman,et al.  Spatiotemporal chromaticity discrimination. , 1969, Journal of the Optical Society of America.

[7]  J. J. Vos,et al.  An analytical description of the line element in the zone-fluctuation model of colour vision. II. The derivation of the line element. , 1972, Vision Research.

[8]  J. J. Vos,et al.  An analytical description of the line element in the zone-fluctuation model of colour vision. I. Basic concepts. , 1972, Vision research.

[9]  S. L. Guth,et al.  Heterochromatic additivity, foveal spectral sensitivity, and a new color model. , 1973, Journal of the Optical Society of America.

[10]  P L Walraven,et al.  A closer look at the tritanopic convergence point. , 1974, Vision research.

[11]  Sensitivity of human color mechanisms to gratings and flicker. , 1975, Journal of the Optical Society of America.

[12]  I. Rentschler,et al.  Pseudo-tritan effect and the vos-walraven line element at low luminance levels , 1976, Vision Research.

[13]  C. R. Ingling,et al.  Orthogonal combination of the three visual channels , 1977, Vision Research.

[14]  D H Kelly,et al.  Two-band model of heterochromatic flicker. , 1977, Journal of the Optical Society of America.

[15]  R. M. Boynton,et al.  Temporal modulation sensitivity of the blue mechanism: Measurements made without chromatic adaptation , 1980, Vision Research.

[16]  J J Koenderink,et al.  Influence of the target size on the deterction threshold for luminance and chromaticity contrast. , 1980, Journal of the Optical Society of America.

[17]  J J Koenderink,et al.  Sensitivity to spatiotemporal combined luminance and chromaticity contrast. , 1981, Journal of the Optical Society of America.