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.


Performance Capture of High-Speed Motion Using Staggered Multi-View Recording

Di Wu, Yebin Liu, Ivo Ihrke, Qionghai Dai, Christian Theobalt
Pacific Graphics 2012


We present a markerless performance capture system that can acquire the motion and the texture of human actors performing fast movements using only commodity hardware. To this end we introduce two novel concepts: First, a staggered surround multi-view recording setup that enables us to perform model-based motion capture on motion-blurred images, and second, a model-based deblurring algorithm which is able to handle disocclusion, self-occlusion and complex object motions. We show that the model-based approach is not only a powerful strategy for tracking but also for deblurring highly complex blur patterns.
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author = {Di Wu and Yebin Liu and Ivo Ihrke and Qionghai Dai and Christian Theobalt},
title = {Performance Capture of High-Speed Motion Using Staggered Multi-View Recording},
journal = {Computer Graphics Forum},
volume = {31},
number = {7},
year = {2012},
pages = {2019--2028},
publisher = {Blackwell Publishing},
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