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How to Derive a Spectrum from an RGB Triplet
July/August 1989 (vol. 9 no. 4)
pp. 95-99

The accurate display of synthetic images requires careful attention to color. Simply modeling color with an RGB triplet leads to color aliasing. Most color antialiasing techniques begin with a specification of color as a spectral energy distribution. There are two apparent hurdles to be overcome to support the spectral model in rendering systems. One is the difficulty of interactively designing a spectral description of a desired color. The other problem is the difficulty of converting existing and useful libraries of RGB triplets into equivalent spectral representations. A simple method that takes as input an RGB triplet viewed on a given monitor and computes a corresponding spectrum for use in a rendering system is presented.

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Andrew S. Glassner, "How to Derive a Spectrum from an RGB Triplet," IEEE Computer Graphics and Applications, vol. 9, no. 4, pp. 95-99, July-Aug. 1989, doi:10.1109/38.31468
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