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jetwhite(Colours)

version 1.23.0.0 (3.45 KB) by David Powers
A continuous colormap that goes from light to dark, cold to warm discriminating all hues

2 Downloads

Updated 13 Jul 2016

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This bright and vivid colormap spirals from black through blue cyan green yellow orange red magenta to white. The colour shades are rotated smoothly through the full 360º range of hues as perceptual lightness varies in a decaying sinusoid from black to white while emphasizing with pure strong well-saturated primary and secondary colours.
This is something I've used for years, and although R2014b includes revamped graphics and a smoother parula colomap replacing jet as the default, the nearest is still jet in terms of the colour gamut, or hot in terms of going from black/dark to white/light. This should work with any version of Matlab and dependencies on toolboxes have been removed. Examples are given that illustrate how to combine colour maps or adjust the gamma to emphasize parts of the spectrum or have a more uniform gradation from light to dark. Jetwhite is designed to maximize the clarity available with colour while providing a reasonable compromise when rendered/copied in greyscale, with adjacent shades differing in both brightness and hue, an maximizing the colour distinction available in the RGB color gamut.

Note that assuring a linear lightness scale tends to produce colours that are muddy or pastel rather than the clear primary and secondary colours jetwhite is designed to punctuate with, e.g. at 64 colours we have 4-10: Blue, 14-20: Teal/Cyan, 24-30: Green, 34-40: Yellow/Orange, 44-50: Red/Pink, 54-60: Magenta. 1-32 are dark/cool colours, 33-64 are light/warm colours - it is designed so that symmetric plots are centred on the yellow/green transition.

Comments and Ratings (1)

The display of color using jetwhite colormap is outstanding compared to other colormaps available. I am using it for displaying multiscale edge map of images, after applying diverse range of filters on them. Excellent colormap code!

Updates

1.23.0.0

documented option to omit number of colors and have it determined from the current colormap

1.22.0.0

keeps removing whitespace - readded

1.22.0.0

update emphasized systematic use of the full range of the colour gamut and the stiking of pure strong saturated primary and secondary colours, unlike the other colour maps that use only a subset and are washed out due to grayscale linearity.

1.22.0.0

typo fixed

1.22.0.0

all whitespace dropped again

1.22.0.0

Note about being warm/cool symmetric around yellow/green transition being useful for symmetric functions/data (two-sided significance/effects) was added to both description and help.

1.21.0.0

back to putting back whitespace

1.21.0.0

be nice if one could see more than 3 lines of the description at a time when editing - minor typo fixed

1.21.0.0

grammar error fixed in description

1.21.0.0

and again

1.21.0.0

blanks again

1.21.0.0

It keeps throwing away blank lines

1.21.0.0

edited to fix redundancy in summary

1.21.0.0

tried again to fix whitespace change

1.21.0.0

formatting change to description

1.21.0.0

1.2 REMOVED dependency on NN toolbox (satlin)

1.11.0.0

Added additional example showing eliminating headroom and footroom to give a Dark Blue to Light Pink range.

1.1.0.0

Added help and example showing how to adjust to different color gamut requirements (RGB display vs CYM printer).
Version 1.1 matches jetwhite(N) syntax to gray(N) syntax to produce a map of N colors and allow simple combination.

MATLAB Release Compatibility
Created with R2007a
Compatible with any release
Platform Compatibility
Windows macOS Linux