Generalized Image Acquisition and Analysis
Acquisition and Analysis of Bispectral Bidirectional Reflectance and Reradiation Distribution Functions
In fluorescent materials, light from a certain band of incident wavelengths is reradiated at longer wavelengths, i.e., with a reduced
per-photon energy. While fluorescent materials are common in everyday life, they have received little attention in computer graphics. Especially, no bidirectional reradiation measurements of fluorescent materials have been available so far. In this paper, we
extend the well-known concept of the bidirectional reflectance distribution function (BRDF) to account for energy transfer between
wavelengths, resulting in a Bispectral Bidirectional Reflectance
and Reradiation Distribution Function (bispectral BRRDF). Using
a bidirectional and bispectral measurement setup, we acquire reflectance and reradiation data of a variety of fluorescent materials,
including vehicle paints, paper and fabric, and compare their renderings with RGB, RGB×RGB, and spectral BRDFs. Our acquisition
is guided by a principal component analysis on complete bispectral
data taken under a sparse set of angles. We show that in order to
faithfully reproduce the full bispectral information for all other angles, only a very small number of wavelength pairs needs to be
measured at a high angular resolution.
Projects
A Reconfigurable Camera Add-On for High Dynamic Range, Multispectral, Polarization, and Light-Field Imaging
SIGGRAPH 2013
Abstract
We propose a non-permanent add-on that enables plenoptic
imaging with standard cameras which we refer to as
KaleidoCamera. Our design is based on a physical copying
mechanism that multiplies a sensor image into a number of
identical copies that still carry the plenoptic information
of interest. Via different optical filters, we can then
recover the desired information. A minor modification of the
design also allows for aperture subsampling and, hence,
light-field imaging. As the filters in our design are
exchangeable, a reconfiguration for different imaging
purposes is possible. We show in a prototype setup that high
dynamic range, multispectral, polarization, and light-field
imaging can be achieved with our design.
Project Page Video Data Set Bibtex
@article{Manakov:13,
author = {Alkhazur Manakov and John Restrepo and Oliver Klehm and Ramon Hegeds and Elmar Eisemann and Hans-Peter Seidel and Ivo Ihrke},
title = {A Reconfigurable Camera Add-On for High Dynamic Range, Multispectral, Polarization, and Light-Field Imaging},
journal = {ACM Trans. on Graphics (SIGGRAPH'13)},
volume = 32, number = 4, year = 2013,
pages = {xx--yy},
}
author = {Alkhazur Manakov and John Restrepo and Oliver Klehm and Ramon Hegeds and Elmar Eisemann and Hans-Peter Seidel and Ivo Ihrke},
title = {A Reconfigurable Camera Add-On for High Dynamic Range, Multispectral, Polarization, and Light-Field Imaging},
journal = {ACM Trans. on Graphics (SIGGRAPH'13)},
volume = 32, number = 4, year = 2013,
pages = {xx--yy},
}