Unifying optimization methods for color filter design

Graham Finlayson, Yuteng Zhu

Research output: Contribution to journalConference articlepeer-review

1 Citation (Scopus)
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Through optimization we can solve for a filter that when the camera views the world through this filter, it is more colorimetric. Previous work solved for the filter that best satisfied the Luther condition: the camera spectral sensitivities after filtering were approximately a linear transform from the CIE XYZ color matching functions. A more recent method optimized for the filter that maximized the Vora-Value (a measure which relates to the closeness of the vector spaces spanned by the camera sensors and human vision sensors). The optimized Luther- and Vora-filters are different from one another. In this paper we begin by observing that the function defining the Vora-Value is equivalent to the Luther-condition optimization if we use the orthonormal basis of the XYZ color matching functions, i.e. we linearly transform the XYZ sensitivities to a set of orthonormal basis. In this formulation, the Luther-optimization algorithm is shown to almost optimize the Vora-Value. Moreover, experiments demonstrate that the modified orthonormal Luther-method finds the same color filter compared to the Vora-Value filter optimization. Significantly, our modified algorithm is simpler in formulation and also converges faster than the direct Vora-Value method.

Original languageEnglish
JournalCEUR Workshop Proceedings
Publication statusPublished - 17 Sep 2020
Event10th Colour and Visual Computing Symposium, CVCS 2020 - Virtual, Gjoivik, Norway
Duration: 16 Sep 202017 Sep 2020


  • Color filters
  • Design optimization
  • Image sensors

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