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Deriving Spectra from Colors and Rendering Light Interference
July/August 1999 (vol. 19 no. 4)
pp. 61-67
In this article we propose a new method for transforming colors into spectra. This method assumes that derived spectra are a linear combination of three basis functions and uses Gaussians as adaptive basis functions. The Gaussian functions are centered in the red, green, and blue wavelength regions, respectively, and their widths are adjusted according to the degrees of saturation of the input colors. Compared with previous transformation methods, this new method is more accurate and can generate spectra with diverse shapes. As an application, we apply the transformation method to rendering light interference using a standard color-based ray tracer by transforming to the spectral domain as needed. The rendered images successfully demonstrate light interference and its important features. Using the same technique, a color-based render can also demonstrate other wavelength-dependent phenomena such as light diffraction, scattering, and dispersion. Since color-based techniques are a standard in computer graphics, this work has the potential to significantly enhance the features and capabilities of general color-based industrial rendering software and graphics platforms.

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Yinlong Sun, F. David Fracchia, Thomas W. Calvert, Mark S. Drew, "Deriving Spectra from Colors and Rendering Light Interference," IEEE Computer Graphics and Applications, vol. 19, no. 4, pp. 61-67, July-Aug. 1999, doi:10.1109/38.773965
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