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Updated: Jul 10, 2026
04:43
Visualizing Visual Adaptation
Published on: April 24, 2017
Light field constancy within natural scenes.
Alexander A Mury1, Sylvia C Pont, Jan J Koenderink
1Department of Physics and Astronomy, Physics of Man, Helmholtz Institute, Utrecht University Princetonplein 5, NL 3584 CC Utrecht, The Netherlands. a.mury@phys.uu.nl
Applied Optics
|October 13, 2007
Summary
Low-order light field properties, like light density and vector, are stable across natural scenes. These components, described using spherical harmonics, correlate with scene geometry, unlike complex high-order properties.
Area of Science:
- Computer Vision
- Computational Imaging
- Physics of Light
Background:
- Natural scene light fields are complex due to high-frequency radiance.
- Low-order light properties significantly influence the appearance of matte materials.
- Gershun's classical work described light fields as 3D vector fields.
Purpose of the Study:
- To extend Gershun's work by describing light fields using tensors.
- To analyze the spatial properties and variations of light fields in natural scenes.
- To investigate the behavior of different orders of light field components.
Main Methods:
- Describing local light fields using spherical harmonics.
- Analyzing low-order components: monopole, dipole, and quadrupole tensors.
- Experimental measurements of light field spatial properties in natural scenes.
Main Results:
- Low-order light field components (monopole, dipole, quadrupole) are relatively constant across scenes.
- High-order light field components exhibit significant spatial variation.
- A strong relationship was found between low-order components and scene geometry.
Conclusions:
- The monopole, dipole, and quadrupole tensors provide a sufficient description for many light fields.
- Low-order light field properties are stable and geometrically linked in natural scenes.
- Understanding these low-order properties is key to analyzing scene appearance and geometry.