Conference Paper

A Planar Light Probe

University of California, San Diego
DOI: 10.1109/CVPR.2006.37 Conference: Computer Vision and Pattern Recognition, 2006 IEEE Computer Society Conference on, Volume: 2
Source: DBLP

ABSTRACT

We develop a novel technique for measuring lighting that exploits the interaction of light with a set of custom BRDFs. This enables the construction of a planar light probe with certain advantages over existing methods for measuring lighting. To facilitate the construction of our light probe, we derive a new class of bi-directional reflectance functions based on the interaction of light through two planar surfaces separated by a transparent medium. Under certain assumptions and proper selection of the two surfaces, we show how to recover Fourier series coefficients of the incident lighting parameterized over the plane. The results are experimentally validated by imaging a sheet of glass with spatially varying patterns printed on either side.

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    • "Ackermann et al. [2] proposes a new technique for accurately modeling reflections on a sphere. Other methods also use either reflective spheres [12] [23] [18] or specially designed planar light probes [3] or analyze shading of known geometric objects [22]. The case of a near point light rigidly attached to a camera has been analyzed for near light photometric stereo [10] and the light fall-off effect due to distance from the light is modeled. "
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    • "They employed a pair of reference spheres as light probes and introduced the difference sphere that can be acquired by differencing the intensities of two image regions of the reference spheres. Alldrin and Kriegman (2006) developed a planar light probe for measuring low frequencies of the lighting. Their method is based on the interaction of light through two planar surfaces separated by a transparent medium . "
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