Generalized Image Acquisition and Analysis

Computational Plenoptic Imaging

The plenoptic function is a ray-based model for light that includes the color spectrum as well as spatial, temporal, and directional variation. Although digital light sensors have greatly evolved in the last years, one fundamental limitation remains: all standard CCD and CMOS sensors integrate over the dimensions of the plenoptic function as they convert photons into electrons; in the process, all visual information is irreversibly lost, except for a two-dimensional, spatially-varying subset - the common photograph. In this state of the art report, we review approaches that optically encode the dimensions of the plenpotic function transcending those captured by traditional photography and reconstruct the recorded information computationally.

Projects

Fluorescent Immersion Range Scanning

Matthias Hullin, Martin Fuchs, Ivo Ihrke, Hans-Peter Seidel, Hendrik P. A. Lensch
In: Proceedings of SIGGRAPH 2008.



Abstract

The quality of a 3D range scan should not depend on the surface properties of the object. Most active range scanning techniques, however, assume a diffuse reflector to allow for a robust detection of incident light patterns. In our approach we embed the object into a fluorescent liquid. By analyzing the light rays that become visible due to fluorescence rather than analyzing their reflections off the surface, we can detect the intersection points between the projected laser sheet and the object surface for a wide range of different materials. For transparent objects we can even directly depict a slice through the object in just one image by matching its refractive index to the one of the embedding liquid. This enables a direct sampling of the object geometry without the need for computational reconstruction. This way, a high-resolution 3D volume can be assembled simply by sweeping a laser plane through the object. We demonstrate the effectiveness of our light sheet range scanning approach on a set of objects manufactured from a variety of materials and material mixes, including dark, translucent and transparent objects.
Project Page Video Data Set

Bibtex

@article{Hullin:2008:FIRS,
title = "Fluorescent Immersion Range Scanning",
author = "Matthias B. Hullin and Martin Fuchs and Ivo Ihrke and Hans-Peter Seidel and
Hendrik P. A. Lensch",
journal = "ACM Transactions on Graphics",
volume = 27,
number = 3,
month = aug,
year = 2008,
pages = "87:1--87:10",
}
Go to project list