Title: Spherical light field rendering in application for analysis by synthesis

Authors: S. Todt, M. Langer, C. Rezk-Salama, A. Kolb, K-D. Kuhnert

Addresses: Institute for Vision and Graphics, University of Siegen, D-57068 Siegen, Germany. ' Institute for Vision and Graphics, University of Siegen, D-57068 Siegen, Germany. ' Institute for Vision and Graphics, University of Siegen, D-57068 Siegen, Germany. ' Institute for Vision and Graphics, University of Siegen, D-57068 Siegen, Germany. ' Institute for Vision and Graphics, University of Siegen, D-57068 Siegen, Germany

Abstract: This paper presents a novel approach for object classification and pose estimation which employs spherical light field rendering to generate virtual views based on the synthesis parameters determined and successively refined in a two-stage analysis by synthesis process. Compared with previous object recognition techniques, the presented approach provides a significant improvement in terms of object classification quality and computational efficiency. Our Graphics Processing Unit based light field renderer exploits per-pixel depth information available with modern Time-Of-Flight sensors like the Photonic Mixer Device camera for high-quality image synthesis in real-time. The renderer uses combined per-pixel RGB and depth values to minimise ghosting artefacts to a non-noticeable amount and employs a spherical parameterisation to ensure full 6 d.f. for virtual view synthesis. Synthetic views are used in our two-stage analysis by synthesis technique which implements a pre-classification and pre-pose-estimation to reduce parameter search space, thus, providing improved object classification quality at less computation time.

Keywords: analysis by synthesis; image-based rendering; spherical light field; object classification; pose estimation; virtual views; object recognition; time-of-flight; TOF sensors; photonic mixer device; PMD camera; image synthesis.

DOI: 10.1504/IJISTA.2008.021293

International Journal of Intelligent Systems Technologies and Applications, 2008 Vol.5 No.3/4, pp.304 - 314

Published online: 18 Nov 2008 *

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