Top view of Resene colours in L*a*b* space.

Augmenting rgb.txt

Dictionary Released Terms
resene-2010 2010-03-05 Resene
NBS-ISCC centroid 2003-12-14 Voluntocracy

As explained in "Color-Name Dictionaries", the Resene and NBS-ISCC dictionaries have higher quality than the other web-published dictionaries. Is it possible to use this improved color dictionary with existing programs?

GNU-Emacs and existing X11 programs depend on rgb.txt color names; so simply replacing rgb.txt is unwise. In X11, the last definition of a color-name in rgb.txt overrides earlier ones; I am assuming that GNU-Emacs (when not running under X11) treats rgb.txt in the same way.

The instructions which follow detail how to append the Resene colour name dictionary to the distributed rgb.txt. I am unaware of a method to define a private color dictionary on these platforms. is a catalog of the 1383 Resene paint colours.

The colors violet, plum, chocolate, lavender, ForestGreen, SaddleBrown, maroon, SpringGreen, coral, PowderBlue, linen, seashell, aquamarine, and azure are visibly different from the rgb.txt colors they override. is a catalog of the updated Resene paint colours compared with the 2001 versions. is a catalog of the 267 NBS-ISCC centroid colors.

The colors DarkGreen, DarkOliveGreen, black, DarkBlue, DarkGray, LightBlue, white, PaleGreen, LightGray, LightGreen, LightYellow, DeepPink, LightPink, DarkViolet, and DarkRed override the same-named X11 colors.

The NBS-ISCC centroid and Resene color dictionaries have no names in common.

X Window System Version 7.1 (Fedora Core 6)

As detailed by Xorg Bugzilla Bug 12293 Cannot install custom rgb.txt file in RHEL 5, Xorg version 7.1 completely ignores rgb.txt (still present at /usr/share/X11/rgb.txt). The reply:
rgb.txt is deprecated, sorry. The default upstream is to build without support for it.

Your distribution may choose to do otherwise, of course, but that's not for to enforce.

There appears to be no way to install a better color dictionary without modifying and rebuilding X11.

X Window System Version 7.0.0 (Fedora Core 5)

Older X11

GNU-Emacs in MS-DOS/Windows

color balls Color-Name Dictionaries
Copyright © 2002, 2003, 2007 Aubrey Jaffer

I am a guest and not a member of the MIT Computer Science and Artificial Intelligence Laboratory.  My actions and comments do not reflect in any way on MIT.
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