2020-10-30T11:14:39Zhttp://edoc.mpg.de/ac_ft_oai.ploai:edoc.mpg.de:2018412011-07-2287:937
Hologrammsynthese und 3D-Analyse in der digitalen Holografie
Petz, Christoph
expertsonly
Die holografische 3D-Visualisierung ist eine gro"se
Herausforderung in der aktuellen Forschung. Neben der
Entwicklung eines entsprechenden Ausgabeger"ats ist
die schnelle Hologrammsynthese eine Voraussetzung f"ur
ein interaktives holografisches Ausgabesystem. In
dieser Arbeit wird ein Algorithmus f"ur die effiziente
Erzeugung digitaler Hologramme mit PC Grafikhardware
vorgestellt. Des Weiteren werden
3D-Rekonstruktionsverfahren von Hologrammen
untersucht, die mit einer CCD-Kamera aufgenommen
werden k"onnen.
Philipps-Universität Marburg
2003
Thesis
http://edoc.mpg.de/201841
de
oai:edoc.mpg.de:2318002010-12-0387:937
A Mobile System for Multi-Video Recording
Ahrenberg, Lukas
Ihrke, Ivo
Magnor, Marcus
expertsonly
\begin{abstract}
We present a portable system to record synchronised, multi-video data
for vision applications such as 3D
reconstruction and video-based rendering of dynamic scenes.
The aim of the project is
to gain access to a greater number of scenes than what a static, wired
indoor studio allows for. The portable acquisition system is
constructed from a number of independent modules, each consisting of
a FireWire camera and a laptop. Our software utilises wireless
networking making the system behave
like a tightly coupled unit without requiring the modules to be
physically connected to each other. The scheme also includes an
external calibration method suitable for general scenes.
The system is scalable and
allows for easy transportation and ad-hoc setup and configuration. We present
recent result
s acquired in the field and their use for free-viewpoint video.
\end{abstract}
Institution of Electrical Engineers
2004
Conference-Paper
http://edoc.mpg.de/231800
urn:ISBN:0863413919
1st European Conference on Visual Media Production (CVMP), Institution of Electrical Engineers, 127-132 (2004)
en
oai:edoc.mpg.de:2318012010-12-0387:937
Spacetime-coherent Geometry Reconstruction from Multiple Video Streams
Magnor, Marcus
Goldluecke, Bastian
Aloimonos, Y.
expertsonly
IEEE
2004
Conference-Paper
http://edoc.mpg.de/231801
urn:ISBN:0-7695-2223-8
2nd International Symposium on 3D Data Processing, Visualization, and Transmission, 3DPVT 2004, IEEE, 365-372 (2004)
en
oai:edoc.mpg.de:2318022010-12-0387:937
Cloth Motion from Optical Flow
Scholz, Volker
Magnor, Marcus
Girod, B.
Magnor, M.
Seidel, H.-P.
expertsonly
This paper presents an algorithm for capturing the motion of deformable
surfaces, in particular textured cloth. In a calibrated multi-camera setup, the
optical flow between consecutive video frames is determined and 3D scene flow
is computed. We use a deformable surface model with constraints for vertex
distances and curvature to increase the robustness of the optical flow
measurements. Tracking errors in long video sequences are corrected by a
silhouette matching procedure. We present results for synthetic cloth
simulations and discuss how they can be extended to real-world footage.
Akademische Verlagsgesellschaft Aka
2004
Conference-Paper
http://edoc.mpg.de/231802
urn:ISBN:3-89838-058-0
Vision, modeling, and visualization 2004 (VMV-04), Akademische Verlagsgesellschaft Aka, 117-124 (2004)
en
oai:edoc.mpg.de:2318062010-12-0387:937
Constrained Inverse Volume Rendering for Planetary Nebulae
Magnor, Marcus
Kindlmann, Gordon
Hansen, Charles
Duric, Neb
Rushmeier, Holly
Turk, Greg
van Wijk, Jarke J.
expertsonly
IEEE
2004
Conference-Paper
http://edoc.mpg.de/231806
urn:ISBN:0-7803-8788-0
IEEE Visualization 2004 : VIS 2004, IEEE, 83-90 (2004)
en
oai:edoc.mpg.de:2318102010-12-0387:937
External camera calibration for synchronized multi-video systems
Ihrke, Ivo
Ahrenberg, Lukas
Magnor, Marcus
expertsonly
UNION Agency
2004
Conference-Paper
http://edoc.mpg.de/231810
urn:ISSN:1213-6972
WSCG '2004 : the 12th International Conference in Central Europe on Computer Graphics, Visualization and Computer Vision 2004 ; short communication papers proceedings, UNION Agency, 537-544 (2004)
en
oai:edoc.mpg.de:2318192010-12-0387:937
Image-Based Tomographic Reconstruction of Flames
Ihrke, Ivo
Magnor, Marcus
Boulic, R.
Pai, D.K.
expertsonly
Eurographics Association
2004
Conference-Paper
http://edoc.mpg.de/231819
urn:ISBN:3-905673-14-2
Computer Animation 2004 : ACM SIGGRAPH / Eurographics Symposium on Computer Animation, Eurographics Association, 367-375 (2004)
en
oai:edoc.mpg.de:2318202010-12-0387:937
Weighted Minimal Hypersurfaces and Their Applications in Computer Vision
Goldluecke, Bastian
Magnor, Marcus
Pajdla, Tomás
Matas, Jirí
expertsonly
Many interesting problems in computer vision can be formulated as a
minimization problem for an {\em energy functional}.
If this functional is given as an integral of a scalar-valued weight function
over an unknown hypersurface, then the minimal surface we are looking for can
be determined as a solution of the functional's Euler-Lagrange equation.
This paper deals with a general class of weight functions
that may depend on the surface point and normal.
By making use of a mathematical tool called {\em the method of the moving
frame},
we are able to derive the Euler-Lagrange equation in arbitrary-dimensional
space and without the need for any surface parameterization.
Our work generalizes existing proofs, and we demonstrate that it
yields the correct evolution equations for a variety of previous
computer vision techniques which can be expressed in terms of our
theoretical framework.
In practical applications, the surface evolution which converges to a
solution of the Euler-Lagrange equation can be implemented using level
set techniques.
The well-known transition to a level set evolution equation,
which we briefly review in this paper, works in the general case as well.
That way, problems involving minimal hypersurfaces in dimensions higher than
three,
which were previously impossible to solve in practice, can now be introduced
and handled by generalized versions of existing algorithms.
As one example, we sketch a novel idea how to reconstruct
temporally coherent geometry from multiple video streams.
Springer
2004
Conference-Paper
http://edoc.mpg.de/231820
urn:ISBN:3-540-21983-8
Computer vision, ECCV 2004 : 8th European Conference on Computer Vision - part II, Springer, 366-378 (2004)
en
oai:edoc.mpg.de:2318212010-12-0387:937
Space-Time Isosurface Evolution for Temporally Coherent 3D Reconstruction
Goldluecke, Bastian
Magnor, Marcus
expertsonly
We model the dynamic geometry of a time-varying scene as a 3D isosurface in
space-time.
The intersection of the isosurface with planes of constant time yields the
geometry at a
single time instant.
An optimal fit of our model to multiple video sequences is
defined as the minimum of an energy functional.
This functional is given by an integral over the entire hypersurface,
which is designed to optimize photo-consistency.
A PDE-based evolution derived from the Euler-Lagrange equation
maximizes consistency with all of the given video data simultaneously.
The result is a 3D model of the scene which varies smoothly over time.
The geometry reconstructed by this scheme
is significantly better than results obtained by space-carving approaches
that do not enforce temporal coherence.
IEEE
2004
Conference-Paper
http://edoc.mpg.de/231821
urn:ISBN:0-7695-2158-4
Proceedings of the 2004 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, CVPR 2004, IEEE, 350-355 (2004)
en
oai:edoc.mpg.de:2378452010-12-0387:937
Axisymmetric reconstruction and 3D visualization of bipolar planetary nebulae
Magnor, Marcus
expertsonly
Max-Planck-Institut für Informatik
2004
Report
http://edoc.mpg.de/237845
en
oai:edoc.mpg.de:5207082010-12-0387:937
Light Field Rendering using Matrix Optics
Ahrenberg, Lukas
Magnor, Marcus
expertsonly
This paper presents a light field rendering framework based on matrix optics.
Matrix optics, in contrast to intersection-based methods such as ray-tracing,
has
the advantage that a generic series of optic operators can be combined into a
single matrix.
This enables us to realize a ``virtual optical bench'' where different setups
can be
easily tested.
We introduce the theoretical foundation of matrix optics and define a set of
operators
suitable for light fields. We then discuss a wavelet compression scheme
for our light field representation. Finally we introduce a real-time rendering
approach based on
matrix optics suitable for both uncompressed and compressed light fields.
Permission
to make digital or hard copies of all or part of this work for personal or
classroom
use is granted without fee provided that copies are not made or distributed for
profit or commercial advantage and that copies bear this notice and the
full citation on the first page. To copy otherwise, or republish, to post on
servers or to redistribute to lists, requires prior specific permission and/or
a fee.
2006
Article
http://edoc.mpg.de/520708
urn:ISSN:1213-6972
Journal of WSCG, v.14, 177-184 (2006)
en
oai:edoc.mpg.de:5207112010-12-0387:937
An Augmented Reality System for Astrnomical Observations
Lintu, Andrei
Magnor, Marcus
expertsonly
Anyone who has gazed through the eyepiece of an astronomical telescope knows
that, with the exception of the Moon and the planets, extra-solar astronomical
objects are disappointing to observe visually. This is mainly due to their low
surface brightness, but also depends on the visibility, sky brightness and
telescope aperture. We propose a system which projects images of astronomical
objects (with focus on nebulae and galaxies),
animations and additional information directly into the eyepiece view of an
astronomical telescope. As the telescope orientation is queried continuously,
the projected image is adapted in real-time to the currently visible field of
view. For projection, a custom-built video projection module with high contrast
and low maximum luminance value was developed. With this technology visitors to
public observatories have the option to experience the richness of faint
astronomical objects while directly looking at them through a telescope.
IEEE
2006
Conference-Paper
http://edoc.mpg.de/520711
urn:ISBN:1-4244-0223-9
Froelich, Bernd; Bowman, Doug; Iwata, Hiroo: IEEE Virtual Reality 2006, IEEE, 119-126 (2006)
en
oai:edoc.mpg.de:5207122011-07-2287:937
PDE-based Surface Reconstruction from Multiple Views using a Surfel Model
Linz, Christian
expertsonly
Variational techniques are a popular approach for reconstructing the surface of
an object. In previous work, the surface is represented either implicitly by
the use of level sets or explicitly as a triangle mesh. In this work, we choose
a point-based surface representation. The rational behind is that the lack of
topology information in point-based models makes it easier to handle
topological changes occurring during the reconstruction.
\par
We first describe our approach for synthetic objects whose geometry is
precisely known. We then transfer this method to real world data and describe
the modified algorithm in detail.
Universität des Saarlandes
2005
Thesis
http://edoc.mpg.de/520712
en
oai:edoc.mpg.de:5207172010-12-0387:937
Multi-View Video Capture of Garment Motion
Scholz, Volker
Magnor, Marcus
expertsonly
We present an image-based algorithm for surface reconstruction of moving
garments from multiple calibrated video cameras. Using a color-coded cloth
texture, we reliably match circular features between different camera views. As
surface model we use an a priori known triangle mesh. By identifying the mesh
vertices with texture elements we obtain a coherent parametrization of the
surface over time without further processing. Missing data points resulting
from self-shadowing are plausibly interpolated by minimizing a thin-plate
functional. The deforming geometry can be used for different graphics
applications, e.g. for realistic retexturing. We show results for real garments
demonstrating the accuracy of the recovered flexible shape.
Technische Universiteit Eindhoven
2006
Conference-Paper
http://edoc.mpg.de/520717
urn:ISBN:978-90-386-2062-6
de With, Peter H.N.; Varekamp, Chris; Farin, Dirk S.; Morvan, Yannick: Content Generation and Coding for 3D-Television, Technische Universiteit Eindhoven, 1-4 (2006)
en
oai:edoc.mpg.de:5207182010-12-0387:937
Computer generated holography using parallel commodity graphics hardware
Ahrenberg, Lukas
Benzie, Philip
Magnor, Marcus
Watson, John
expertsonly
This paper presents a novel method for using programmable graphics hardware to
generate fringe patterns for SLM-based
holographic displays. The algorithm is designed to take the programming
constraints imposed by the graphics hardware pipeline
model into consideration, and scales linearly with the number of object points.
In contrast to previous methods we do not have to use the Fresnel
approximation. The technique can also be used on
several graphics processors in parallel for further optimization.
We achieve real-time frame rates for objects consisting of a few hundred
points at a resolution of
$960 \times 600$ pixels and over $10$ frames per second for $1000$ points.
2006
Article
http://edoc.mpg.de/520718
urn:ISSN:1094-4087
Optics Express, v.14, 7636-7641 (2006)
en
oai:edoc.mpg.de:5207232011-07-2287:937
Hole Filling in Images and in Video Sequences
El-Abed, Sascha
expertsonly
During the last years, many image processing and manipulation techniques have
evolved and have become more and more popular, reaching from scienti c theory
of mathematical image processing to general-purpose software for artistic image
editing, e.g. Adobe Photoshop [Ado06] or GIMP [GIM06]. These tools are adequate
for many tasks, but require a high amount of user interaction. In this work, we
focus on the image inpainting problem: given an image, an undesired object is
to be removed from the image, and the "hole" arising is lled in a visually
plausible way. To this end, we extend existing work on this topic, and apply
the basic idea
to a higher-dimensional problem: video inpainting. Here, an undesired object is
to be removed from a video sequence. As a video is nothing else than a sequence
of images in time, this requires a method producing consistently lled holes
over time. Compared to many existing approaches for image and video inpainting,
we aim at a method with as little user interaction as possible. The minimum
interaction required
for our method is the selection of the region to be inpainted.
Universität des Saarlandes
2007
Thesis
http://edoc.mpg.de/520723
en
oai:edoc.mpg.de:5207242011-07-2287:937
New Editing Techniques for Video Post-Processing
Scholz, Volker
expertsonly
This thesis contributes to capturing 3D cloth shape, editing cloth texture and
altering object shape and motion in multi-camera and monocular video
recordings. We propose a technique to capture cloth shape from a 3D scene flow
by
determining optical flow in several camera views. Together with a silhouette
matching constraint we can track and reconstruct cloth surfaces in long video
sequences. In the area of garment motion capture, we present a system to
reconstruct time-coherent triangle meshes from multi-view video recordings.
Texture mapping of the acquired triangle meshes is used to replace the recorded
texture with new cloth patterns. We extend this work to the more challenging
single camera view case. Extracting texture deformation and shading effects
simultaneously enables us to achieve texture replacement effects for garments
in monocular video recordings. Finally, we propose a system for the keyframe
editing of video objects. A color-based segmentation algorithm together with
automatic video inpainting for filling in missing background texture allows us
to edit the shape and motion of 2D video objects. We present examples for
altering object trajectories, applying non-rigid deformation and simulating
camera motion.
Universität des Saarlandes
2007
PhD-Thesis
http://edoc.mpg.de/520724
en
oai:edoc.mpg.de:5207262010-12-0387:937
Realistic Solar Disc Rendering
Lintu, Andrei
Haber, Jörg
Magnor, Marcus
expertsonly
University of West Bohemia
2005
Conference-Paper
http://edoc.mpg.de/520726
urn:ISBN:80-903100-7-9
Skala, Vaclav: WSCG 2005, the 13th International Conference in Central Europe on Computer Graphics, Visualization and Computer Vision 2005 : in co-operation with EUROGRAPHICS W S C G ' 2005, FULL PAPERS, University of West Bohemia, 79-86 (2005)
en