"Statistical Approaches to Local Motion Estimation"

Rudolf Mester, J.W. Goethe University, Frankfurt

Friday, April 4, 2003 at 3:00 P.M.

Lubrano Conference Room

The natural characteristics of image signals and the statistics of measurement noise are decisive for designing optimal filter sets and optimal estimation methods in signal processing. Astonishingly, this principle has so far only partially found its way into the field of motion estimation.

The talk will discuss two main issues: First, the estimation of local motion is considered to be equivalent to an optimum signal subdivision into an ideally oriented signal, parameterized by the motion direction, and an additive noise component. For optimizing this subdivision and finding the motion direction, models for the signal (i.e. its autocovariance) and for the noise are required. For practical implementations this motivates quite naturally to employ the theory of steerable filters and leads to an extension of the classical tensor-based motion estimation scheme. Secondly, the talk will discuss how a Wiener-type MMSE filtering of the image signal, based on a simple covariance model for moving images, helps in designing appropriate filter sets for differential or tensor-based methods in optical flow estimation. This approach provides means for integrating prior knowledge on the distribution of expected motion vectors and possibly non i.i.d. noise statistics (colored noise or oriented disturbances).

Rudolf Mester (*1958) studied electrical engineering with an emphasis on communication technology at the Technical University of Aachen, Germany. After having obtained his diploma degree in 1983, he performed research work in industrial and academic projects on image processing and image coding and earned his doctoral degree (Dr.-Ing.) from RWTH Aachen in 1988 with a thesis on statistical model based image segmentation. After a short period with Philips Data Systems, Siegen, Dr. Mester joined the Communications Research Institute of Robert Bosch GmbH, Hildesheim, where he established a computer vision and image interpretation group. He initiated and conducted numerous internal as well as several national and European joint research projects especially in the field of applying computer vision to traffic-related problems and security systems. In October 1995, Dr. Mester was appointed professor of applied physics at Goethe University, Frankfurt am Main. Currently, his research interests are focussed on statistical signal and image processing methods, the construction of robust and reliable vision algorithms and flexible vision systems as well as the theoretical foundations for "seeing machines".

Host: Michael Black