farver (version 1.1.0)

compare_colour: Calculate the distance between colours

Description

There are many ways to measure the distance between colours. farver provides 5 different algorithms, ranging from simple euclidean distance in RGB space, to different perceptual measures such as CIE2000.

Usage

compare_colour(from, to = NULL, from_space, to_space = from_space,
  method = "euclidean", white_from = "D65", white_to = white_from)

Arguments

from, to

Numeric matrices with colours to compare - the format is the same as that for convert_colour(). If to is not set from will be compared with itself and only the upper triangle will get calculated

from_space, to_space

The colour space of from and to respectively. to_space defaults to be the same as from_space.

method

The method to use for comparison. Either 'euclidean', 'cie1976', 'cie94', 'cie2000', or 'cmc'

white_from, white_to

The white reference of the from and to colour space. Will only have an effect for relative colour spaces such as Lab and luv. Any value accepted by as_white_ref() allowed.

Value

A numeric matrix with the same number of rows as colours in from and the same number of columns as colours in to. If to is not given, only the upper triangle will be returned.

Examples

# NOT RUN {
r <- t(col2rgb(rainbow(10)))
h <- t(col2rgb(heat.colors(15)))

# Compare two sets of colours
compare_colour(r, h, 'rgb', method = 'cie2000')

# Compare a set of colours with itself
compare_colour(r, from_space = 'rgb', method = 'cmc')
# }