Perceptually Uniform Colour Maps

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These colour maps are released under the Creative Commons BY License. A summary of the conditions can be found here. Basically, you are free to use these colour maps in anyway you wish as long as you give appropriate credit. If you find this work useful please cite this site and the paper:

Peter Kovesi. Good Colour Maps: How to Design Them.
arXiv:1509.03700 [cs.GR] 2015

29 Colour Map Formats...

I find it astonishing that so many different formats have been created for something as simple as a table of colours. In many cases packages do not formally define their colour map formats and I have had to deduce the format from example maps provided to me. If you need a format that is not in this list below please let me know and I will do my best to add it. As I do not have access to all these packages I am not able to test all these formats. If you encounter any problems please let me know. Any other feedback you might have is welcome.

Adobe Colour Table
Adobe's .act format for use within Photoshop.
ArcGIS style file
The maps are approximated using multi-part ramps with 64 segments. Please note that I have had to apply an adjustment to the colour ramps in an attempt to compensate for some strangeness in the way ArcGIS converts CIELAB values in the style file to RGB. I have been unable to reconcile the ArcGIS conversion results with those I obtain from any other published conversion routines, details are here. I am not entirely satisfied with the result but I believe the final ramps, as rendered, are reasonably close to their original design.
Cloud Compare
Place the colour maps in a folder and load using the Color Scales Manager Dialog
COMSOL Multiphysics
Place the files in the folder:
you will then need to restart COMSOL for the colour maps to be available
CSV floating point RGB values in the range 0-1.
Can be used with the Madagascar package.
CSV integer RGB values in the range 0-255.
ER Mapper, Intrepid
ER Mapper's .lut format. Used by Intrepid and I think these can also be used with MapInfo.
Geosoft Oasis montaj
Geosoft's .tbl format.
GeoGraphix binary .PAL format.
Dynamic color palette tables (.cpt) files for GMT, The Generic Mapping Tools.
If you use gmt makecpt to construct a static CPT file from these files you should avoid using a large z interval when using the -T option otherwise the properties of some colour maps may be compromised. Choose a z interval such that the total range is divided into at least 64 intervals.
Paradigm GOCAD .cmap format.
Find where your Gwyddion installation has been placed in your system and copy the files into the folder:
ImageJ's .lut format.
Julia PerceptualColourMaps.jl
For those working in Julia this package allows you to generate all these colour maps for use with various Julia plotting packages.
They are also available directly within the Plots.jl package as the colorcet color gradient library.
IHS Markit Kingdom's .CLB format. Note these colour maps have 230 colour values which is the maximum that can be specified in the .CLB format.
Landmark DecisionSpace Geophysics
Landmark's .cl2 and the newer .clx formats.
MagicPlot These colour maps are available in MagicPlot's format at
MATLAB colorcet.m
A stand-alone function that contains pre-generated arrays of the perceptually uniform colour maps.
MicroImages TNTmips No need to download
These colour maps are incorporated in their latest release.
Micromine No need to download
These colour maps are included in Micromine 2018.
NCL, NCAR Command Language .rgb files.
ParaView CETperceptual_ParaView.xml
Load using: Color map editor -> Choose preset -> Import
Petrel, DUG Insight
Schlumberger Petrel .alut format. These can also be used with DownUnder GeoSolutions Insight.
Petrosys .pal format. These colour maps are now also available directly from Petrosys.
This package gives you access to these colour maps for use with Python plotting programs such as Bokeh, Matplotlib, HoloViews GeoViews, and Datashader. Thanks to James Bednar.
See also:
The pals package gathers together a number of colour maps including the CET perceptually uniform colour maps and also includes R code for generating the colour map test image.
QGIS style file CETperceptual_QGIS.xml
The maps are approximated using multi-part ramps with 64 segments. Load the style file using the QGIS menu sequence:
Settings -> Style Manager -> Share -> Import
Golden Software's Surfer .clr format.

This xkcd cartoon seems very appropriate.

Colour map naming

There are too many maps for them to be given nice individual names. I did devise a semi-automatic naming scheme that described each map's key characteristics in terms of its type (linear, diverging etc), the lightness range, colour sequence, and mean chroma. However the resulting names were too complex, too long to type, and impossible to remember.

In practice I simply refer to the colour maps by one or two characters to indicate whether the map is Linear (L), Diverging (D), Rainbow (R), Cyclic(C), Isoluminant (I), or Colour Blind (CB), followed by a number.

To ensure appropriate lexical ordering of colour maps when they are loaded into a package I have constructed the zip files so that the Linear and Diverging map names use 2 digit numbers with a leading 0 where needed. Thus, within any of the zip files the linear grey scale will be labeled CET-L01, the heat colour map 'CET-L03', and the blue-white-red diverging map 'CET-D01', etc.