@inproceedings{SchmidtVogtNiemann2002, author = {Schmidt, Jochen and Vogt, F. and Niemann, H.}, title = {Nonlinear Refinement of Camera Parameters using an Endoscopic Surgery Robot}, series = {Proceedings of IAPR Conference on Machine Vision Applications (MVA)}, booktitle = {Proceedings of IAPR Conference on Machine Vision Applications (MVA)}, year = {2002}, abstract = {We present an Approach for non linea roptimization of the parameters of an endoscopic camera mounted on a surgery robot. The goal is to generate a depth map for each image in order to enhance the quality of medical light fields. The pose information provided by the robot is used as an initialization, where especially the orientation isi naccurate. Refinement of intrinsic and extrinsic camera parameters is performed by minimizing the back-projectionerror of 3-D points that are reconstructed by triangulation from image Feature stracked over an image sequence. Optimization of the camera parameters results in an enhancement of Rendering Quality in two ways: More accurate parameters lead to better interpolation as well as to better depth maps for approximating the scenegeometry.}, language = {en} } @inproceedings{SchmidtNiemannVogt2002, author = {Schmidt, Jochen and Niemann, H. and Vogt, F.}, title = {Dense Disparity Maps in Real-Time with an Application to Augmented Reality}, series = {Proceedings Sixth IEEE Workshop on Applications of Computer Vision (WACV 2002), pages 225-230, Orlando, FL USA}, booktitle = {Proceedings Sixth IEEE Workshop on Applications of Computer Vision (WACV 2002), pages 225-230, Orlando, FL USA}, year = {2002}, abstract = {This work presents a technique for computing dense disparity maps from a binocular stereo camera system. The methods are applied in an Augmented Reality setting for combining real and virtual worlds with proper occlusions. The proposed stereo correspondence technique is based oil area matching and facilitates an efficient strategy by using the concept of a three-dimensional similarity accumulator whereby occlusions are detected and object boundaries are extracted correctly. The main contribution of this paper is the way we fill the accumulator using absolute differences of images and computing a mean filter on these difference images. This. is. where the main advantages of the accumulator approach can be exploited, since all entries can be computed in parallel and thus extremely efficient. Additionally, we-perform an asymmetric correction step and a post-processing of the disparity maps that maintains object edges.}, language = {en} } @inproceedings{SchmidtNiemann2002, author = {Schmidt, Jochen and Niemann, H.}, title = {Using Quaternions for Parametrizing 3D Rotations in Unconstrained Nonlinear Optimization}, series = {Vision, Modeling, and Visualization 2001, pages 399-406, Stuttgart, Germany}, booktitle = {Vision, Modeling, and Visualization 2001, pages 399-406, Stuttgart, Germany}, year = {2002}, abstract = {In this paper we address the problem of using quaternions in unconstrained nonlinear optimization of 3-D rotations. Quaternions representing rotations have four elements but only three degrees of freedom, since they must be of norm one. This constraint has to be taken into account when applying e.g. the Levenberg-Marquardt algorithm, a method for unconstrained nonlinear optimization widely used in computer vision. We propose an easy to use method for achieving this. Experiments using our parametrization in photo grammetric b{\"u}ndle -adjustment are presented at the end of the paper.}, language = {en} } @inproceedings{WenhardtSchmidtNiemann2002, author = {Wenhardt, S. and Schmidt, Jochen and Niemann, H.}, title = {Didaktische Aufbereitung von Methoden des Rechnersehens f{\"u}r virtuelle Vorlesungen}, series = {Forschungsbeitr{\"a}ge zur Didaktik der Informatik - Theorie, Praxis, Evaluation}, booktitle = {Forschungsbeitr{\"a}ge zur Didaktik der Informatik - Theorie, Praxis, Evaluation}, year = {2002}, abstract = {Dieser Artikel stellt ein Konzept f¨ur eine Online-Vorlesung im Rahmen der virtuellen Hochschule Bayern vor. Zun{\"a}chst werden kurz die fachlichen Inhalte erl¨autert, die es zu vermitteln gilt. Nach dieser Einf{\"u}hrung wird auf die Umsetzung der Inhalte in eine dem neuen Medium Internet angemessene Form eingegangen. Dies betrifft vor allem die ausgew{\"a}hlten Techniken, die zur Wissensvermittlung eingesetzt werden. Ein besonderer Schwerpunkt liegt auf der M{\"o}glichkeit durch Interaktivit{\"a}t das Wissen experimentell zu vertiefen und somit eine Verbindung zwischen dem theoretisch Gelernten und dem praktisch Erfahrenen herzustellen. Weiterhin wird eine Vielfalt an Kommunikationsm¨oglichkeiten vorgestellt, da Kommunikation eine wichtige soziale Komponente im Lernprozess und h¨aufig entscheidend f¨ur den Erfolg ist.}, language = {de} }