Measuring BRDFs of Immersed Materials
We investigate the effect of immersing real-world materials
into media of different refractive indices. We show, that
only some materials follow the Fresnel-governed
behaviour. In reality, many materials exhibit unexpected
effects such as stronger localized highlights or a
significant increase in the glossy reflection due to
microgeometry. In this paper, we propose a new measurement
technique that allows for measuring the BRDFs of materials
that are immersed into different media.
Projects

Property and Lighting Manipulations for Static Volume Stylization Using a Painting Metaphor
TVCG 2014
Abstract
Although volumetric phenomena are important for realistic
rendering and can even be a crucial component in the image,
the artistic control of the volume’s appearance is
challenging. Appropriate tools to edit volume properties are
missing, which can make it necessary to use simulation
results directly. Alternatively, high-level modifications
that are rarely intuitive, e.g., the tweaking of noise
function parameters, can be utilized.
Our work introduces a solution to stylize single-scattering
volumetric effects in static volumes. Hereby, an artistic
and intuitive control of emission, scattering and extinction
becomes possible, while ensuring a smooth and coherent
appearance when changing the viewpoint. Our method is based
on tomographic reconstruction, which we link to the
volumetric rendering equation. It analyzes a number of
target views provided by the artist and adapts the volume
properties to match the appearance for the given
perspectives. Additionally, we describe how we can optimize
for the environmental lighting to match a desired scene
appearance, while keeping volume properties
constant. Finally, both techniques can be combined. We
demonstrate several use cases of our approach and illustrate
its effectiveness.
Video Bibtex
@article{Klehm:14,
author = {Oliver Klehm and Ivo Ihrke and Hans-Peter Seidel and Elmar Eisemann},
title = {Property and Lighting Manipulations for Static Volume Stylization Using a Painting Metaphor},
journal = {Transactions of Visualization and Computer Graphics},
year = 2014,
pages = {xx--yy},
}
author = {Oliver Klehm and Ivo Ihrke and Hans-Peter Seidel and Elmar Eisemann},
title = {Property and Lighting Manipulations for Static Volume Stylization Using a Painting Metaphor},
journal = {Transactions of Visualization and Computer Graphics},
year = 2014,
pages = {xx--yy},
}