python-colormath 1.0.1 Released

Greg Taylor gtaylor at
Fri Jun 5 15:43:12 CEST 2009


After much testing and refinement in an industrial setting, python-colormath
has been released to the public under the GPLv3.

What is python-colormath?
python-colormath is a developer-oriented module that abstracts a number of
color math operations behind a small set of classes representing color
spaces (IE: RGB, CIE Lab, XYZ, and LCH, etc.). Color conversions, delta E
comparisons, and density calculations are all relatively involved, but are
hid behind the simple API. For example, conversions from RGB to CMY and CMYK
are trivial, while conversions from Spectral to LCHab are equally so (even
though much more math happens behind the scenes).

Quantitative comparisons of the difference between two colors may be
calculated using one of several delta E formulas. Colors are automatically
converted to the appropriate comparison color space and the delta E formula
returns the result with no real effort on your part.

For those working with spectral power distributions, the module can convert
them to color spaces or ANSI/ISO density values. This is particularly useful
when trying to minimize the difference in the readings of two different
spectrophotometric devices.

It is perhaps best to consider python-colormath as a more advanced, complete
version of Python's own colorsys module. The number of supported color
spaces, operations, and capabilities far exceeds colorsys (which is simple
and minimalistic by design).

Avoid color calculation errors
One of the biggest benefits of this module is that it was designed and
implemented by members of the Graphic Communications and print industries.
The developers having a formal background in color science leaves you with a
very complete, "correct" implementation of color math. Unlike the other
color libraries, python-colormath avoids many of the problems with varying
types of RGB, color illuminants and observer angles, and many different
things that go on behind the scenes.

python-colormath is also rigorously tested through its use in a previously
commercial color management system. Additionally, all conversions are unit
tested and monitored for deviations wich each change to the codebase. This
ensures consistent, repeatable results through each release.

Where is python-colormath?
Getting Started/Website/Development:



support at

I hope this fairly niche module is useful to someone else out there!
Gregory Taylor

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