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“Film Recording of Digital Color Images”
by Robert Hall Wallis
May 1975
The goal of this study is the formulation of a technique for the quantitative control of color film. The specific application is the recording of digital images from a color monitor (or scanner) onto color film with maximum colorimetric fidelity. In as much as human color perception is three-dimensional in nature, the recording process can be modeled as the passage of a three-dimensional signal through a trinary channel. Consequently, the distortions imposed upon the signal by channel can be neutralized by a suitable pre-distortion of the input three-vector. Specifically, the pre-distortion should be the mathematical inverse of the channel mapping.
A hierarchy of methods for the inversion of the channel mapping are developed, and tested. Although the numerical errors associated with the inversion process are shown to be insignificant, some subjective errors are apparent in the photographic reproduction if the predistortion is based on traditional fidelity criterion for color matching. A fidelity criterion based on a more relevant model of color vision, with particular attention to chromatic adaption, is developed. Using this model, photographic reproductions of color monitor images can be produced with excellent fidelity.