Jonas August, PhD
Project Scientist
Healthcare Robotics Center
Robotics Institute
Carnegie
Mellon University
Research
Geometry and uncertainty are coupled
aspects of my interests in computer
vision and medical imaging. On the one hand, we seek descriptions of
the structures in the physical world
in the language of differential geometry.
On the other, our observations
of this world come in the form of amorphous,
noisy images, without the discrete
structures we effortlessly call
"objects". I am interested
in "organizing" images into such
objects, and I use the tools
of Markov processes and random fields to
derive algorithms from first
principles. Not only are such ideas relevant
for helping a roving robot deal
with its environment or for understanding
the neural architecture of the
primary visual cortex in primates, but they
can be exploited to improve medical
image quality. For example, I am
exploring the use of probabilistic
techniques for removing the often
catastrophic "streaking artifacts"
in X-ray CT scans. In addition, by
building in a model of the local
geometry of curves, one can obtain
vascular structures from
low quality medical images.
Projects
Parallel methods in regularized tomography
"doc": a GNU/Linux cluster for medical
imaging applications
Interests
Medical imaging, regularization,
image artifact removal, mathematical modeling
Image statistics: What structure
can be observed? Can it be modeled tractably?
Finding curves in images:
inference of 1-d structures in 2-d images
Putting together curves to
form objects: contour fragment grouping
Stably
representing objects: Hierarchies, axial descriptions, "shape"
Doctoral Dissertation
The
Curve Indicator Random Field
Selected Publications
``The Role of Non-Overlap in Image Registration,'' in
Proceedings, Information Processing in Medical Imaging (IPMI), 2005. Download paper in PDF.
``Weakly-Supervised Segmentation of Non-Gaussian Images via Histogram Adaptation,'' in Proceedings, MICCAI 2003. Download paper in PDF.
``Volterra Filtering of Noisy Images
of Curves,''in Proceedings, European Conference on Computer
Vision, Copenhagen, May 2002. Download paper in PDF.
``Decoupling the Equations of Regularized
Tomography,''in Proceedings, 2002 IEEE International Symposium
on Biomedical Imaging, Washington,
D.C., July 7--10, 2002. Download paper in PDF.
``A Markov Process Using
Curvature for Filtering Curve Images,'' with Steven Zucker, in Energy
Minimization Methods in Computer Vision and Pattern Recognition, Nice,
2001. Download paper in gzipped
PostScript or PDF.
``A Generative Model of
Curve Images with a Completely-Characterized Non-Gaussian Joint
Distribution,''
with Steven Zucker, in Workshop on Statistical and Computational
Theories
of Vision at International Conference on Computer Vision, July
2001. Download paper in gzipped
PostScript or PDF.
``A Field Model for Contour
Organization and Partial Differential Equations,'' with Steven Zucker,
in Workshop on Perceptual Organization in Computer Vision at
International
Conference on Computer Vision, July 2001. Download paper in gzipped
PostScript or PDF.
``The Curve Indicator
Random Field: Curve Organization via Edge Correlation,'' with Steven
Zucker, Chapter. 15, pp. 265-287, in Perceptual Organization in
Artificial
Vision Systems, Boyer and Sarkar, Eds., Kluwer Academic, Boston, 2000.
Download paper in gzipped
PostScript.
``On the Evolution of
the Skeleton,'' in IEEE International Conference on Computer Vision,
September 1999. Download paper in gzipped
PostScript. Movies (animated GIFs) of evolving objects and their
skeletons: hand
, hand
skeleton, pimple, semiligature,
branch
lengthening despite boundary shortening, junction
switch (an "internal" skeleton instability is flagged), birth
``Ligature Instabilities
and the Perceptual Organization of Shape,'' with Kaleem Siddiqi and
Steven
Zucker,Computer Vision and Image Understanding 76(3): 231-243, 1999.
Download in gzipped
PostScript.
``Contour Fragment Grouping
and Shared, Simple Occluders,'' with Kaleem Siddiqi and Steven Zucker,
Computer Vision and Image Understanding, 76(2): 146-162, 1999. Download
in gzipped
PostScript.
``Duality in Perceptual
Organization: Grouping vs. Shape Decomposition,'' in IEEE Workshop
in Perceptual Organization in Computer Vision, June 1998.
``Fragment grouping via
the principle of perceptual occlusion,'' inInternational Conference
on Pattern Recognition, August 1996.
Education
- Ph.D. (Yale,
2001)
- M.Phil. (Yale, 1999)
- M.Sc. (Yale, 1999)
- M.Eng. (McGill, 1996)
- B.Eng. (McGill, 1993)
Resume / Curriculum Vitae
Download in PDF.
Friends and Colleagues
Ohad Ben-Shahar
Athos Georghiades
Patrick Huggins
Takeo Kanade
Ben Kimia
David Mumford
Kaleem Siddiqi
Lance Williams
Song-Chun Zhu
Steve Zucker
/etc
Contact:
Jonas August
The Robotics Institute
Carnegie Mellon University
5000 Forbes Avenue
Pittsburgh, PA 15213-3890
Tel: (412) 268-1314
FAX: (412) 268-6436
Email: jonas@cs.cmu.edu
