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Hyperspectral environmental illumination maps: characterizing directional spectral variation in natural environments.

ABSTRACT: Objects placed in real-world scenes receive incident light from every direction, and the spectral content of this light may vary from one direction to another. In computer graphics, environmental illumination is approximated using maps that specify illumination at a point as a function of incident angle. However, to-date, existing public databases of environmental illumination specify only three colour channels (RGB). We have captured a new set of 12 environmental illumination maps (eight outdoor scenes; four indoor scenes) using a hyperspectral imaging system with 33 spectral channels. The data reveal a striking directional variation of spectral distribution of lighting in natural environments. We discuss limitations of using daylight models to describe natural environmental illumination.

SUBMITTER: Morimoto T

PROVIDER: S-EPMC7028397 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Hyperspectral environmental illumination maps: characterizing directional spectral variation in natural environments.

Morimoto Takuma T Kishigami Sho S Linhares João M M JMM Nascimento Sérgio M C SMC Smithson Hannah E HE

Optics express 20191001 22

Objects placed in real-world scenes receive incident light from every direction, and the spectral content of this light may vary from one direction to another. In computer graphics, environmental illumination is approximated using maps that specify illumination at a point as a function of incident angle. However, to-date, existing public databases of environmental illumination specify only three colour channels (RGB). We have captured a new set of 12 environmental illumination maps (eight outdoo ...[more]

PMID: 31684444

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