EURASIP Journal on Advances in Signal Processing
Volume 2007 (2007), Article ID 60696, 10 pages
doi:10.1155/2007/60696
Research Article

Calibrating Distributed Camera Networks Using Belief Propagation

Dhanya Devarajan and Richard J. Radke

Department of Electrical, Computer, and Systems Engineering, Rensselaer Polytechnic Institute, Troy 12180, NY, USA

Received 4 January 2006; Revised 10 May 2006; Accepted 22 June 2006

Academic Editor: Deepa Kundur

Copyright © 2007 Dhanya Devarajan and Richard J. Radke. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

We discuss how to obtain the accurate and globally consistent self-calibration of a distributed camera network, in which camera nodes with no centralized processor may be spread over a wide geographical area. We present a distributed calibration algorithm based on belief propagation, in which each camera node communicates only with its neighbors that image a sufficient number of scene points. The natural geometry of the system and the formulation of the estimation problem give rise to statistical dependencies that can be efficiently leveraged in a probabilistic framework. The camera calibration problem poses several challenges to information fusion, including overdetermined parameterizations and nonaligned coordinate systems. We suggest practical approaches to overcome these difficulties, and demonstrate the accurate and consistent performance of the algorithm using a simulated 30-node camera network with varying levels of noise in the correspondences used for calibration, as well as an experiment with 15 real images.