cie {pavo} | R Documentation |
CIE colour spaces
Description
Calculates coordinates and colorimetric variables that represent reflectance spectra in either the CIEXYZ (1931), CIELAB (1971), or CIELCh (1971) colourspaces.
Usage
cie(
vismodeldata,
space = c("XYZ", "LAB", "LCh"),
visual = c("cie2", "cie10"),
illum = c("D65", "bluesky", "forestshade")
)
Arguments
vismodeldata |
(required) quantum catch color data. Can be either the result
from |
space |
(required) Choice between XYZ (default), LAB, or LCh colour models. |
visual |
the visual system used when estimating XYZ values, if
|
illum |
the illuminant used when estimating XYZ values, if
|
Value
Object of class colspace
containing:
-
X, Y, Z
: Tristimulus values. -
x, y, z
: Cartesian coordinates, when usingspace = XYZ
. -
L, a, b
: Lightness,L
, and colour-opponenta
(redness-greenness) andb
(yellowness-blueness) values, in a Cartesian coordinate space. Returned when usingspace = LAB
. -
L, a, b, C, h
: Lightness,L
, colour-opponenta
(redness-greenness) andb
(yellowness-blueness) values, as well as chromaC
and hue-angleh
(degrees), the latter of which are cylindrical representations ofa
andb
from the CIELAB model. Returned when usingspace = LCh
.
Author(s)
Thomas White thomas.white026@gmail.com
References
Smith T, Guild J. (1932) The CIE colorimetric standards and their use. Transactions of the Optical Society, 33(3), 73-134.
Westland S, Ripamonti C, Cheung V. (2012). Computational colour science using MATLAB. John Wiley & Sons.
Stockman, A., & Sharpe, L. T. (2000). Spectral sensitivities of the middle- and long-wavelength sensitive cones derived from measurements in observers of known genotype. Vision Research, 40, 1711-1737.
CIE (2006). Fundamental chromaticity diagram with physiological axes. Parts 1 and 2. Technical Report 170-1. Vienna: Central Bureau of the Commission Internationale de l Eclairage.
Examples
# Load floral reflectance spectra
data(flowers)
# Estimate quantum catches, using the cie10-degree viewer matching function
vis.flowers <- vismodel(flowers, visual = "cie10", illum = "D65", vonkries = TRUE, relative = FALSE)
# Model floral spectra in the CIEXYZ space
flowers.ciexyz <- colspace(vis.flowers, space = "ciexyz")
# Model floral spectra in the CIELab space
flowers.cielab <- colspace(vis.flowers, space = "cielab")
# Model floral spectra in the CIELch space
flowers.cielch <- colspace(vis.flowers, space = "cielch")