Editing Munsell color system (section)

=== Specifying a color ===
A color is fully specified by listing the three numbers for hue, value, and chroma in that order. For instance, a purple of medium lightness and fairly saturated would be 5P 5/10 with 5P meaning the color in the middle of the purple hue band, 5/ meaning medium value (lightness), and a chroma of 10 (see swatch). An [[achromatic color]] is specified by the syntax {{code|N V/}}. For example, a medium grey is specified by "N 5/".

In computer processing, the Munsell colors are converted to a set of "HVC" numbers. The V and C are the same as the normal chroma and value. The H (hue) number is converted by mapping the hue rings into numbers between 0 and 100, where both 0 and 100 correspond to 10RP.<ref>ASTM, Standard D 1535-08, "Standard Practice for Specifying Color by the Munsell System," approved January 1, 2008.</ref>

As the Munsell books, including the 1943 renotation, only contains colors for some points in the Munsell space, it is non-trivial to specify an arbitrary color in Munsell space. [[Interpolation]] must be used to assign meanings to non-book colors such as "2.8Y 6.95/2.3", followed by an ''inversion'' of the fitted Munsell-to-xyY transform. The ASTM has defined a method in 2008, but Centore 2012 is known to work better.<ref>{{cite journal |last1=Centore |first1=Paul |title=An open-source inversion algorithm for the Munsell renotation |journal=Color Research & Application |date=December 2012 |volume=37 |issue=6 |pages=455–464 |doi=10.1002/col.20715}}</ref>