Create LUV Colors

This function creates colors of class “LUV”; a subclass of the virtual color-class class.

LUV(L, U, V, names)

Arguments

L, U, V

these arguments give the L, U and V coordinates of the colors. The values can be provided in separate L, U and V vectors or in a three-column matrix passed as L.

names

a vector of names for the colors (by default the row names of L are used).

Value

An object of class LUV which inherits from class color.

Details

The L, U and V values give the coordinates of the colors in the CIE (1976) \(L^*u^*v^*\) space. This is a transformation of the 1931 CIE XYZ space which attempts to produce perceptually based axes. Luminance takes values between 0 and 100, and the other coordinates typically take values between -100 and 100, although these values can also be exceeded by highly saturated colors. The \(u\) and \(v\) coordinates measure positions on green/red and blue/yellow axes.

See also

RGB, HSV, XYZ, LAB, polarLAB, polarLUV.

Author

Ross Ihaka

Examples

## Show the LUV space
set.seed(1)
x <- sRGB(runif(1000), runif(1000), runif(1000))
y <- as(x, "LUV")
head(x)
#>              R         G        B
#> [1,] 0.2655087 0.5308088 0.871805
head(y)
#>             L         U         V
#> [1,] 56.02127 -26.35485 -80.16156
plot(y)