Color Coordinate Conversion

COLORS, a FORTRAN90 code which converts color data from one system to another.

The color coordinate systems considered include CIELAB, CIELUV, CIExyY, CIEXYZ, CMY, CMYK, HLS, HSI, HSV, HVC, LCC, NCS, PhotoYCC, RGB, Y'CbCr, Y'IQ, Y'PbPr and Y'UV.

Color specification and conversion is a suprisingly difficult subject. For a particular situation, getting more red just means increasing some number. But to accurately try to take a given color that shows up on one computer monitor screen, write down the color specification numbers and the illumination, and then figure out the corresponding color specification numbers in a different color system on a different device (a printer, a television) with a different illumination is actually an extraordinary art.


The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.


COLORS is available in a FORTRAN90 version.

Related Data and Programs:

COLOR, a dataset directory which describes colors by name, triples of integers between 0 and 255, or triples of real numbers between 0 and 1.



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Source Code:

Last revised on 10 June 2020.