A paper published at Journal of Electronic Imaging

A paper published at Journal of Electronic Imaging

Created
December 2, 2021
Tags
PaperMulti-spectral Imaging
Updated
December 15, 2021

We are pleased to announce that our paper “Color saturation control by modulating spectral power distribution of illumination using color enhancement factors" has been published at Journal of Electronic Imaging (JEI).

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Color enhancement factors are spectral components modulating the spectral power distribution (SPD) of illumination for interactive color saturation control. They can enhance more than one target colors simultaneously or independently while maintaining the current color appearance. However, previous methods have the following fundamental drawbacks.

  • Color enhancement factors obtained by the previous methods highly depend on the lighting system.
  • The effect of color muting — decreasing saturation of the target color — is quite limited, due to the optimization of color enhancement factors for increasing color saturation.

In this work, we tackle those two issues and develop a new type of color enhancement factors that can both enhance and mute color saturation.

  1. We first simulate color saturation enhancement & muting for determining parameters of color enhancement factors, such as the center wavelength and full width at half maximum. The results demonstrate that maximum variations of color muting become almost the same as those of color enhancement.
  2. We also found that SPDs of illumination for increasing and decreasing color saturation of red, green, and blue have three peaks respectively, and that they appear for enhancement and muting alternately.
  3. In addition, we revealed that color enhancement factors for enhancing and muting color saturation were roughly symmetric.

We performed experiments using a newly designed twelve-color LED lighting system and demonstrate color enhancing and muting effects by the proposed method. Finally, we present the results of color restoration of discolored cultural heritage and coloring simulation of industrial products.