Unifying Optimization Methods for Color Filter Design
- URL: http://arxiv.org/abs/2006.13622v1
- Date: Wed, 24 Jun 2020 11:01:56 GMT
- Title: Unifying Optimization Methods for Color Filter Design
- Authors: Graham Finlayson and Yuteng Zhu
- Abstract summary: 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).
- Score: 3.8073142980733
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: 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.
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