| estimateSoilColor {aqp} | R Documentation |
Estimate dry soil colors from moist soil colors and vice versa.
Description
Soil color is typically described at dry and moist conditions. This function attempts to estimate soil color at dry or moist condition when one is missing. Estimation proceeds as:
convert Munsell notation to CIELAB color coordinates via
munsell2rgb()apply scaling, rotation, and translation parameters in CIELAB color space
locate closest Munsell chip to CIELAB coordinates via
col2munsell()
Estimation of dry from moist soil color state is not guaranteed to be symmetric with estimation of moist from dry.
Usage
estimateSoilColor(hue, value, chroma, sourceMoistureState = c("dry", "moist"))
Arguments
hue |
vector of Munsell hue ('10YR', '2.5Y', etc.) |
value |
vector of Munsell value (2,2.5 2.5, 3, 5, 6, etc.) |
chroma |
vector of Munsell chroma (2, 3, 4, etc.) |
sourceMoistureState |
character, source colors are either 'dry' or 'moist' |
Details
Scaling, rotation, and translation parameters for shifting between dry <–> moist CIELAB coordinates was determined using vegan::procrustes(), from those official series descriptions (OSD) where moist and dry soil colors were available.
Estimates for colors having a (dry or moist) Munsell value of 10 are not likely correct.
This is still a work in progress.
Value
data.frame of estimated colors in Munsell notation. The sigma column contains CIE2000 color contrast metric values describing the perceptual distance between estimated color in CIELAB coordinates and closest Munsell chip.
Author(s)
D.E. Beaudette
Examples
# keep examples from using more than 2 cores
data.table::setDTthreads(Sys.getenv("OMP_THREAD_LIMIT", unset = 2))
estimateSoilColor(hue = '10YR', value = 3, chroma = 3, sourceMoistureState = 'moist')
# note that estimation is not symmetric
estimateSoilColor(hue = '10YR', value = 5, chroma = 3, sourceMoistureState = 'dry')