Refine
Year of publication
- 2015 (13) (remove)
Document Type
- Bachelor Thesis (10)
- Master's Thesis (3)
Keywords
- OpenGL (3)
- Android (2)
- Compute Shader (2)
- Grafikkarte (2)
- 360 Grad (1)
- 360 degree (1)
- Android development (1)
- Androidentwicklung (1)
- Applikation (1)
- Augmented Reality (1)
Institute
- Institut für Computervisualistik (13) (remove)
For definite isolation and classification of important features in 3D multi-attribute volume data, multidimensional transfer functions are inalienable. Yet, when using multiple dimensions, the comprehension of the data and the interaction with it become a challenge. That- because neither the control of the versatile input parameters nor the visualization in a higher dimensional space are straightforward.
The goal of this thesis is the implementation of a transfer function editor which supports the creation of a multidimensional transfer function. Therefore different visualization and interaction techniques, like Parallel Coordinates, are used. Furthermore it will be possible to choose and combine the used dimensions interactively and the rendered volume will be adapted to the user interaction in real time.
In this thesis, we deal with the question if challenge, flow and fun in computer games are related to each other, and which influence the motivational, psychological components motivation of success, motivation of failure and the chance of success do have. In addition, we want to know if a free choice in the level of difficulty is the optimal way to flow. To examine these theories, a study based on an online survey was executed, in which the participants played the game “flOw“. The results were evaluated with the help of a two-factorial analysis of variance with repeated measurement and tests on correlation. Thereby we found out that there actually exists a relation between challenge, flow and fun and that motivation does matter indirectly.
In this thesis, an interactive application is developed for Android OS. The application is about a virtual-reality game. The game is settled in the genre of first-person shooters and takes place in a space scenario. By using a stereo renderer, it is possible to play the game combined with virtual-reality glasses.
Das Thema dieser Arbeit ist die Entwicklung einer hardwarebeschleunigten Einzelbildkompression zur Videoübertragung. Verfahren zur Einzelbildkompressionrn existieren bereits seit längerer Zeit. Jedoch genügen die gängigen Verfahren nicht den Anforderungen der Echtzeit und Performanz, um während einer Videoübertragung ohne spürbare Latenz zum Einsatz zu kommen. In dieser Arbeit soll einer der geläufigsten Algorithmen zur Bildkompression auf Parallelisierbarkeit, unter zu Hilfenahme der Grafikkarte, untersucht werden, um Echtzeitfähigkeit während der Kompression und Dekompression von computergenerierten Bildern zu erreichen. Die Ergebnisse werden evaluiert und in den Rahmen aktueller Verfahren parallelisierter Kompressionstechniken eingeordnet.
Today, augmented reality is becoming more and more important in several areas like industrial sectors, medicine, or tourism. This gain of importance can easily be explained by its powerful extension of real world content. Therefore, augmented realty became a way to explain and enhance the real world information. Yet, to create a system which can enhance a scene with additional information, the relation between the system and the real world must be known. In order to establish this relationship a commonly used method is optical tracking. The system calculates its relation to the real world from camera images. To do so, a reference which is known is needed in the scene to serve as an orientation. Today, this is mostly a 2D-marker or a 2D-texture. These are placed in the real world scenery to serve as a reference. But, this is an intrusion in the scene. That is why it is desirable that the system works without such an additional aid. An strategy without manipulating the scene is object-tracking. In this approach, any object from the scene can be used as a reference for the system. As an object is far more complex than a marker, it is harder for the system to establish its relationship with the real world. That is why most methods for 3D-object-tracking reduce the object by not using the whole object as reference. The focus of this thesis is to research how a whole object can be used as a reference in a way that either the system or the camera can be moved in any 360 degree angle around the object without loosing the relation to the real world. As a basis the augmented reality framework, the so called VisionLib, is used. Extensions to this system for 360 degree tracking are implemented in different ways and analyzed in the scope of this work. Also, the different extensions are compared. The best results were achieved by improving the reinitialization process. With this extension, current camera images of the scene are given to the system. With the hek of these images, the system can calculate the relation to the real world faster in case the relation went missing.
The present work introduces a rigid-body physics engine, focusing on the collision detection by GPU. The increasing performance and accessibility of modern graphics cards ensures that they can be also used for algorithms that are meant not only for imaging. This advantage is used to implement an efficient collision detection based on particles. The performance differences between CPU and GPU are presented by using a test environment.
This thesis shows an interaction of primitives in a three-dimensional space which is done by gestures. Functions which are difficult to do by gestures without any absolute feeling of the position are implemented with a touchscreen. Besides the touchscreen a second input device, a Leap-Motion, is used to obtain data of the motion of the hand. To get its data the Leap-Motion uses two CCD-cameras and three infrared LEDs. The interactions that can be done without any feedback of the absolute position are the translation, rotation and scale. These three and the movement through space are implemented as gestures in this thesis. This is done in Blender with the BlenderrnGame Engine and Python. The only function which has been implemented for the touchscreen is to select an object. Later on, a comparative control of the mouse was invented to contrast it with the control of the gestures. There are two big differences between these two controls. On the one hand, the gesture controls can be done in a three-dimensional space but most people aren't used to it yet. On the other hand, there is just a two-dimensional input possibility with the mouse control. Otherwise it is familiar to most persons. The evaluation should reveal if people prefer interaction by mouse control or by gestures. The result shows that the prefered control is done by the mouse. However in some categories of the tests the gestures are quite close to the result of the mouse.
This thesis deals with the development of an interactive Android card game. As an example, the Hebrew game Yaniv was implemented. Focus is the elaboration of required background components and the corresponding implementation in that application. Required game processes will be screened and a possible solution will be identified.
The mitral valve is one of the four valves in the human heart. It is located in the left heart chamber and its function is to control the blood flow from the left atrium to the left ventricle. Pathologies can lead to malfunctions of the valve so that blood can flow back to the atrium. Patients with a faulty mitral valve function may suffer from fatigue and chest pain. The functionality can be surgically restored, which is often a long and exhaustive intervention. Thorough planning is necessary to ensure a safe and effective surgery. This can be supported by creating pre-operative segmentations of the mitral valve. A post-operative analysis can determine the success of an intervention. This work will combine existing and new ideas to propose a new approach to (semi-)automatically create such valve models. The manual part can guarantee a high quality model and reliability, whereas the automatic part contributes to saving valuable labour time.
The main contributions of the automatic algorithm are an estimated semantic separation of the two leaflets of the mitral valve and an optimization process that is capable of finding a coaptation-line and -area between the leaflets. The segmentation method can perform a fully automatic segmentation of the mitral leaflets if the annulus ring is already given. The intermediate steps of this process will be integrated into a manual segmentation method so a user can guide the whole procedure. The quality of the valve models generated by the method proposed in this work will be measured by comparing them to completely manually segmented models. This will show that commonly used methods to measure the quality of a segmentation are too general and do not suffice to reflect the real quality of a model. Consequently the work at hand will introduce a set of measurements that can qualify a mitral valve segmentation in more detail and with respect to anatomical landmarks. Besides the intra-operative support for a surgeon, a segmented mitral valve provides additional benefits. The ability to patient-specifically obtain and objectively describe the valve anatomy may be the base for future medical research in this field and automation allows to process large data sets with reduced expert dependency. Further, simulation methods that use the segmented models as input may predict the outcome of a surgery.
Thematik dieser Arbeit ist das dreidimensionale Image-Warping für diffuse und reflektierende Oberflächen. Das Warpingverfahren für den reflektierenden Fall gibt es erst seit 2014. Bei diesem neuen Algorithmus treten Artefakte auf, sobald ein Bild für einen alternativen Blickwinkel auf eine sehr unebene Fläche berechnet werden soll.
In dieser Arbeit wird der Weg von einem Raytracer, der die Eingabetexturen erzeugt, über das Warpingverfahren für beide Arten der Oberflächen, bis zur Optimierung des Reflective-Warping-Verfahrens erarbeitet. Schließlich werden die Ergebnisse der Optimierung bewertet und in den aktuellen sowie zukünftigen Stand der Technik eingeordnet.