color-tools is a Ruby library to provide RGB, CMYK, and other colourspace
support to applications that require it. It also provides 152 named RGB
colours. It offers 152 named RGB colours (184 with spelling variations)
that are commonly supported and used in HTML, SVG, and X11 applications.
A technique for generating a monochromatic contrasting palette is also
included.

WWW: https://github.com/ripta/color-tools