Color

I've been learning about color recently, and reading about the CIELAB color space[1].

It's been adjusted to more closely match the human perceptual field, so color similarity in that space is closer to what it is through our eyes.

It has three dimensions, lightness (L), green/red (a) and blue/yellow (b). The color space can be transformed into polar coordinates so the three dimensions become lightness (l), chroma (C*) and hue (h°).

One issue with the CIELAB color space is some inaccuracy in the blue area of the spectrum; the mapping there isn't quite correct. Other color spaces address this, such as the OKLAB color space[2]. It has the same dimensions, and also has a version with polar coordinates.

Color links:

• Colorcet color maps[3]
• Colour displays for categorical images[4]
• Points of view: colorblindness[5]
• The CIEDE2000 Color-Difference Formula: Implementation Notes, Supplementary Test Data, and Mathematical Observations[6]
• Paul Tol's notes: Qualitative colour schemes[7]

Last updated Tue May 17 2022 in Berkeley, CA

Links

1: https://en.wikipedia.org/wiki/CIELAB_color_space

2: https://bottosson.github.io/posts/oklab/

3: https://colorcet.holoviz.org/user_guide/Categorical.html

4: https://onlinelibrary.wiley.com/doi/10.1002/col.20327

5: https://www.nature.com/articles/nmeth.1618

6: http://www2.ece.rochester.edu/~gsharma/ciede2000/ciede2000noteCRNA.pdf

7: https://personal.sron.nl/~pault/#sec:qualitative

Backlinks

/thought/psychology.gmi

/thought/perception.gmi