Generalized Image Acquisition and Analysis
Maximum Mipmaps for Fast, Accurate, and Scalable Dynamic Height Field Rendering
This paper presents a GPU-based, fast, and accurate dynamic height field rendering technique that scales well to large scale height fields. Current real-time rendering algorithms for dynamic height fields employ approximate ray-height field intersection methods, whereas accurate algorithms require pre-computation in the order of seconds to minutes and are thus not suitable for dynamic height field rendering. We alleviate this problem by using maximum mipmaps, a hierarchical data structure supporting accurate and efficient rendering while simultaneously lowering the pre-computation costs to negligible levels. Furthermore, maximum mipmaps allow for view-dependent level-of-detail rendering. In combination with hierarchical ray-stepping this results in an efficient intersection algorithm for large scale height fields.
Projects
Discovering the Structure of a Planar Mirror System from Multiple Observations of a Single Point
CVPR 2013
Abstract
We investigate the problem of identifying the position of a
viewer inside a room of planar mirrors with unknown geometry
in conjunction with the room’s shape parameters. We consider
the observations to consist of angularly resolved depth
measurements of a single scene point that is being observed
via many multi-bounce interactions with the specular room
geometry.
Applications of this problem statement include areas such as
calibration, acoustic echo cancelation and time-of-flight
imaging. We theoretically analyze the problem and derive
sufficient conditions for a combination of convex room
geometry, observer, and scene point to be
reconstructable. The resulting constructive algorithm is
exponential in nature and, therefore, not directly
applicable to practical scenarios.
To counter the situation, we propose theoretically devised
geo- metric constraints that enable an efficient pruning of
the solution space and develop a heuristic randomized search
algorithm that uses these constraints to obtain an effective
solution. We demon- strate the effectiveness of our
algorithm on extensive simulations as well as in a
challenging real-world calibration scenario.
Bibtex
@inproceedings{Reshetouski:13,
author = {Ilya Rehsetouski and Alkhazur Manakov and Ayush Bhandari and Ramesh Raskar and Hans-Peter Seidel and Ivo Ihrke},
title = {Discovering the Structure of a Planar Mirror System from Multiple Observations of a Single Point},
booktitle = {Proceedings of CVPR},
year = 2013,
pages = {xx--yy},
}
author = {Ilya Rehsetouski and Alkhazur Manakov and Ayush Bhandari and Ramesh Raskar and Hans-Peter Seidel and Ivo Ihrke},
title = {Discovering the Structure of a Planar Mirror System from Multiple Observations of a Single Point},
booktitle = {Proceedings of CVPR},
year = 2013,
pages = {xx--yy},
}