vorgelegt von

To my parent

Multi-modal Scene Understanding Using Probabilistic Models

First, I would like to especially thank my advisor, Prof. Gerhard Sagerer, for his openminded support, continual encouragement, and fruitful discussions. His way of mediating experiences beyond technical aspects of research was very inspiring for me. I enjoyed many joint conference visits with him and the cooperative organization of the workshop “Integration of Speech and Image Understanding ” which was associated with the International Conference of Computer Vision 1999. Secondly, I very much acknowledge Prof. Sven Dickinson from the University of Toronto for being the second reviewer in my thesis committee. His comments encourage me to continue research in this area. I have to thank Enno Ohlebusch for his offhanded readiness to substitute Prof. Dickinson during my defence who had to cancel his flight because of the terrorist attack happening in New York, Sept. 2001. The present thesis was embedded in the Collaborative Research Center 360 “Situated Artificial Communicators ” that has been funded by the German Research Foundation. I joined the research project “Interaktion sprachlicher und visueller Informationsverarbeitung” (Interaction of speech and image processing) for three exciting and inspirin