Convert sRGB color coordinates to the closest n Munsell chips in the munsell lookup table. This function will be replaced by col2Munsell() in aqp 2.1.
rgb2munsell(color, colorSpace = c("CIE2000", "LAB", "sRGB"), nClosest = 1)a data.frame or matrix object containing sRGB coordinates in the range of (0,1)
distance metric (colorspace) to use for finding the closest chip: CIE2000 is the most accurate but requires farver >= 2.0.3, Euclidean distance in CIELAB is a close second, while Euclidean distance in sRGB is not at all accurate and should only be used for demonstration purposes.
number of closest Munsell colors to return (valid range is 1-20)
an (NA-padded) data.frame containing hue, value, chroma, and distance (dE00 when colorSpace = 'CIE2000', Euclidean distance otherwise) to nearest matching color.
This function is fully vectorized and will pad output with NA-records when NA are present in color.
http://ncss-tech.github.io/AQP/ http://www.brucelindbloom.com/index.html?ColorCalcHelp.html https://www.munsellcolourscienceforpainters.com/MunsellAndKubelkaMunkToolbox/MunsellAndKubelkaMunkToolbox.html http://www.cis.rit.edu/mcsl/online/munsell.php
# keep examples from using more than 2 cores
data.table::setDTthreads(Sys.getenv("OMP_THREAD_LIMIT", unset = 2))
# Munsell notation to sRGB triplets [0-1]
color <- munsell2rgb(
the_hue = c('10YR', '2.5YR', '5YR'),
the_value = c(3, 5, 2.5),
the_chroma = c(5, 6, 2),
return_triplets = TRUE
)
# result is a data.frame
color
#> r g b
#> 1 0.3754983 0.2555129 0.09093377
#> 2 0.6613729 0.4212891 0.30856225
#> 3 0.2897926 0.2154340 0.18009210
# back-transform sRGB -> closest Munsell color
# sigma is the dE00 color contrast metric
rgb2munsell(color)
#> rgb2munsell() will be deprecated in aqp 2.1, please use col2Munsell() instead.
#> hue value chroma sigma
#> 1 10YR 3.0 5 4.410418e-14
#> 2 2.5YR 5.0 6 2.796756e-15
#> 3 5YR 2.5 2 3.177668e-14