Dataset Information

Reconciling the statistics of spectral reflectance and colour.

ABSTRACT: The spectral reflectance function of a surface specifies the fraction of the illumination reflected by it at each wavelength. Jointly with the illumination spectral density, this function determines the apparent colour of the surface. Models for the distribution of spectral reflectance functions in the natural environment are considered. The realism of the models is assessed in terms of the individual reflectance functions they generate, and in terms of the overall distribution of colours which they give rise to. Both realism assessments are made in comparison to empirical datasets. Previously described models (PCA- and fourier-based) of reflectance function statistics are evaluated, as are improved versions; and also a novel model, which synthesizes reflectance functions as a sum of sigmoid functions. Key model features for realism are identified. The new sigmoid-sum model is shown to be the most realistic, generating reflectance functions that are hard to distinguish from real ones, and accounting for the majority of colours found in natural images with the exception of an abundance of vegetation green and sky blue.

SUBMITTER: Griffin LD

PROVIDER: S-EPMC6839875 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Publications

Reconciling the statistics of spectral reflectance and colour.

Griffin Lewis D LD

PloS one 20191108 11

The spectral reflectance function of a surface specifies the fraction of the illumination reflected by it at each wavelength. Jointly with the illumination spectral density, this function determines the apparent colour of the surface. Models for the distribution of spectral reflectance functions in the natural environment are considered. The realism of the models is assessed in terms of the individual reflectance functions they generate, and in terms of the overall distribution of colours which ...[more]

PMID: 31703060

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Dataset Information

Reconciling the statistics of spectral reflectance and colour.

Publications

Reconciling the statistics of spectral reflectance and colour.

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