SPATIOTEMPORAL ANALYSIS OF DEFORMABLE CONTOURS by Yusuf Sinan Akgul

It is common to employ a shape model or motion model for the analysis of nonrigid motion. However, adequate amount of information about the motion type or the structure under deformation is not usually available. As a result, general assumptions have to be used for the employed model resulting in relatively inefficient and less robust systems due to inadequate constraints. In this work, we present a number of techniques that deal with the problems of spatiotemporal modeling of contours which assume the most general constraints in both spatial and temporal domains. The main application area of these techniques are analysis of medical images, especially ultrasound image sequences. The first problem addressed, which is crucial for a successful operation of the systems working on medical images, includes proper utilization of user-supplied-data in the spatiotemporal analysis process and adding extra spatiotemporal information after the main analysis step in order to increase efficiency. We also introduce a technique to obtain the qualitative local deformations from the spatiotemporal contour analysis. Another set of techniques deals with the excess amount of data that results from the increased number of constraints and larger search spaces on which these constraints have to be imposed. We use scale spaces to analyze the underlying images in order to concentrate on promising image parts. We also introduce a multilevel optimization technique that minimizes the model energy using the results of the analysis of the underlying images. Finally, we combine spatiotemporal analysis of contours with the modeling of the ultrasound imaging, thus increasing