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VR Fresken
(2018)
Das Projekt VR Fresken setzte sich zum Ziel, mit Hilfe von virtueller Realität im Rahmen einer Museumsausstellung historisch rekonstruierte Räume und deren Deckenfresken interaktiv erlebbar zu machen. In dieser Arbeit werden die eingesetzten Techniken und Technologien beleuchtet, der Anwendungsfall der VR für den Einsatz im Museum untersucht, sowie eine Evaluation der Software im Alltagsbetrieb im Museum durchgeführt.
Volumetrische Beleuchtung
(2018)
Volumetric lighting is a common lighting phenomena in nature and carries an important role in the realistic appearance of computergenerated images. This thesis explains the physical background of this phenomena and lists common modells for visualising volumetric lighting in Computergraphics. Following this, this thesis compares three methods for visualising volumetric lighting with modern graphics hardware and compares these according to their abilities, restrictions and performance in an OpenGL implementation.
Es wird ein Augmented-Reality Ansatz zur Erforschung modularer OSGi-Softwaresysteme präsentiert. Der Prototyp wird unter der Verwendung der Microsoft HoloLens implementiert. Module, wie Komponenten und Packages, werden in einer virtuellen Stadt dargestellt. Dieser Ansatz ermöglicht es dem Anwender, die Software-Architektur mittels intuitiver Navigation zu erkunden: Spracheingabe, Blickpunkt- und Gestenkontrolle. Eine multifunktionale Benutzeroberfläche wird vorgestellt, die für verschiedene Zielgruppen adaptiert werden kann. Viele veröffentlichte Visualisierungen weisen keine klare Zielgruppendefinition auf. Das Konzept kann leicht auf andere Darstellungsformen, wie beispielsweise der Inselmetapher übertragen werden. Erste Ergebnisse einer Evaluierung, die mittels kleiner strukturierter Interviews gewonnen werden konnten, werden präsentiert. Die Probanden mussten vier Programm-verständnis Aufgaben lösen und ihren Aufwand, sowie ihre Arbeitsbelastung einschätzen. Die Ergebnisse bilden eine gute Grundlage für weitere Forschung im Bereich der Software- Visualisierung in Augmented Reality.
This bachelor thesis’s objective is to offer the reader insight into the discrete Fourier transform, the discrete cosine transform and the discrete Hadamard-Walsh transform in the context of image processing, and also to compare these transformations under various aspects. For this purpose the term of transformation, originated in linear algebra, will be explained and applied to image processing. Subsequently, the understanding of the Fourier transform will successively be built up and connected to the two remaining transforms. Finally, the transformations will be compared and their usefulness in relation to image processing will be explained.
How does gameplay influence the fun in video games? This article will search for an answer to this question by using a self-made video game created from scratch. This video game will be programmed in two versions with differences only in gameplay. Several test persons are then to play this game. A survey will be answered afterwards. In order to gain values that are merely influenced by gameplay changes, thoughts on the game design and conception were made. Results suggest that gameplay has a big impact on fun in video games. But gameplay isn't the only responsible factor that makes a video game amusing. Psychological aspects are present when the gameplay of a video game changes.
The present thesis gives an overview of the general conditions for the programming of graphics cards. For this purpose, the most important Application Programming Interfaces (APIs) available on the market are presented and compared. Subsequently, two standard algorithms from the field data processing, prefix sum and radixsort are presented and examined with regard to the implementation with parallel programming on the GPU. Both algorithms were implemented using the OpenGL-API and OpenGL compute shaders. Finally, the execution times of the two algorithms were compared.
In dieser Arbeit wird ein System zur Erzeugung und Darstellung stereoskopischen Video-Panoramen vorgestellt. Neben der theoretischen Grundlagen werden der Aufbau und die Funktionsweise dieses Systems erläutert.
Dazu werden spezielle Kameras verwendet, die Panoramen aufnehmen
können und zur Wiedergabe synchronisiert werden. Anschließend wird ein Renderer implementiert, welcher die Panoramen mithilfe einer VirtualReality Brille stereoskopisch darstellen kann. Dafür werden separate Aufnahmen für die beiden Augen gemacht und getrennt wiedergegeben. Zum Abschluss wird das entstandene Video-Panorama mit einem Panorama eines schon bestehenden Systems verglichen.
In this bachelor thesis a code for astrophysical self-gravitating fluid
simulation is developed. The code runs mainly on the GPU. Minimal
simplifications of the physical model and some parameters for accuracy
and tuning allow simulations to be performed at interactive framerates
on most modern consumer grade computers that feature a dedicated
graphics card. It is used to simulate the birth of stars from a turbulent
molecular cloud. Multiple features of star formation, like accretion
discs and fragmentation, can be observed in the simulation, even when
low particle counts are used.
This paper describes the robots TIAGo and Lisa used by team homer@UniKoblenz of the University of Koblenz-Landau, Germany, for the participation at the RoboCup@Home 2018 in Montreal, Canada. Further this paper serves as qualification material for the RoboCup-@Home participation in 2018. A special focus is put on novel system components and the open source contributions of our team. This year the team from Koblenz won the biggest annual scientianc robot competition in Montreal in the RoboCup@Home Open Platform track for the third time and also won the RoboCup@Home German Open for the second time. As a research highlight a novel symbolic imitation learning approach was demonstrated during the annals. The TIAGo robotic research platform was used for the first time by the team. We have released packages for object recognition, a robot face including speech synthesis, mapping and navigation, speech recognition interface via android and a GUI. The packages are available (and new packages will be released) on http://wiki.ros.org/agas-ros-pkg. Further information can be found on our project page http://homer.uni-koblenz.de.
This paper describes the robot Lisa used by team homer@UniKoblenz of the University of Koblenz Landau, Germany, for the participation at the RoboCup@Home 2017 in Nagoya, Japan. A special focus is put on novel system components and the open source contributions of our team. We have released packages for object recognition, a robot face including speech synthesis, mapping and navigation, speech recognition interface via android and a GUI. The packages are available (and new packages will be released) on
http://wiki.ros.org/agas-ros-pkg.
This paper describes the robot Lisa used by team
homer@UniKoblenz of the University of Koblenz Landau, Germany, for the participation at the RoboCup@Home 2016 in Leipzig, Germany. A special focus is put on novel system components and the open source contributions of our team. We have released packages for object recognition, a robot face including speech synthesis, mapping and navigation, speech recognition interface via android and a GUI. The packages are available (and new packages will be released) on http://wiki.ros.org/agas-ros-pkg.
In der Computergrafik stellte das echtzeitfähige
Rendern von Haaren und Fell ein Problem dar. Die
Berechnung der Beleuchtung, Schattierung und
Transparenz erfordert einen hohen Rechenaufwand,
welcher sich negativ auf die Performanz auswirkt.
Doch durch verbesserte Hardware und neue Verfahren
ist es möglich, solch komplexe Effekte in Echtzeit
zu simulieren. In folgender Arbeit werden die
Grundlagen des Renderings von Haaren erläutert.
Außerdem wurde im Rahmen der Arbeit eine
echtzeitfähige Demo implementiert, deren zugrunde
liegende Verfahren und Funktionalitäten beschrieben
werden. Um die Demo zu evaluieren wurde die mögliche
Anzahl an Bildern pro Sekunde bei Modellen
unterschiedlicher Komplexität gemessen. Schließlich
wurden die Ergebnisse mit Bildern von echten Haaren
verglichen.
In no other field of computer science has the hardware been evolved more
quickly than in computer graphics. Therefore the GPU offers, aside from
the pure rendering of triangles, a bunch of further pipeline steps that allows
visualisation of other graphics objects, like freeform surfaces.
This bachelor’s thesis is about the rendering of freeform surfaces, in particular
bezier surfaces. For that reason an implementation for management
and visualisation of bézier surfaces was created for the rendering framework
of the university Koblenz (CVK). For this purpose first a triangulation
was implemented and finally a tesselation of bezier surfaces with normals
and texture coordinates, as well as the handling of trim curves.
Raytracing mit Vulkan
(2018)
Der Schwerpunkt der vorliegenden Bachelorarbeit war die Entwicklung eines einfachen Raytracerprogrammes unter der Verwendung der Vulkan API, und das Einschätzen des Mehraufwandes im Vergleich zum Performancegewinn. Das Programm wird in dieser Arbeit vorgestellt. Die Vulkan Komponente des Programms wird detailliert erklärt. Anschließend wird das Programm mit einem, unter der Verwendung von OpenGL geschriebenen, ähnlichen Raytracerprogramm verglichen. Beide Programme verwenden dabei den gleichen Raytracer, der im Fragmentshader implementiert ist. Der Test ergibt, dass der mithilfe von Vulkan geschriebene Raytracer deutlich langsamer ist, als das zum Vergleich dienende OpenGL Programm.
Helicopters are crucial in today’s life. A vast amount of applications prove
their range, which are not coverable by other types of aircraft. But they are
very complex systems, both, technically and physically. This is one of the
reasons why pilot training for helicopters is quite challenging. In the last
two decades flight simulators became a supplementary instrument in the
educational process of pilots. With flight simulators it is possible to replay
uncommon or dangerous situations. In this thesis a simple flight simulator
for helicopters will be developed based on rigid body physics. The foundation is a simplified rotor model which omits complex fluid dynamics. This
helps to keep the implementation simple and illustrative as well as provide simulation rates at real-time. The modules are implemented within
the Unreal Engine in such way, that changing helicopter characteristics is
very easy.
Mit der Microsoft Kinect waren die ersten Aufnahmen von synchronisierten Farb- und Tiefendaten (RGB-D) möglich, ohne hohe finanzielle Mittel aufwenden zu müssen und neue Möglichkeiten der Forschung eröffneten sich. Mit fortschreitender Technik sind auch mobile Endgeräte in der Lage, immer mehr zu leisten. Lenovo und Asus bieten die ersten kommerziell erwerblichen Geräte mit RGB D-Wahrnehmung an. Mit integrierten Funktionen der Lokalisierung, Umgebungserkennung und Tiefenwahrnehmung durch die Plattform Tango von Google gibt es bereits die ersten Tests in verschiedenen Bereichen des Rechnersehens z.B. Mapping. In dieser Arbeit wird betrachtet, inwiefern sich ein Tango Gerät für die Objekterkennung eignet. Aus den Ausgangsdaten des Tango Geräts werden RGB D-Daten extrahiert und für die Objekterkennung verarbeitet. Es wird ein Überblick über den aktuellen Stand der Forschung und gewisse Grundlagen bezüglich der Tango Plattform gegeben. Dabei werden existierende Ansätze und Methoden für eine Objekterkennung auf mobilen Endgeräten untersucht. Die Implementation der Erkennung wird anhand einer selbst erstellten Datenbank von RGB-D Bildern gelernt und getestet. Neben der Vorstellung der Ergebnisse werden Verbesserungen und Erweiterungen für die Erkennung vorgeschlagen.
In this bachelor thesis a system for the simulation of the movements of molecules is developed. The calculation of the forces between chemically bonded atoms as well as intermolecular forces is done almost entirely on the GPU. The visualization of the simulation happens at an interactive framerate. To achieve rendering in realtime on off-the-shelf graphics cards, apt optimizations and slight abstractions of the underlying physical models are needed. One can control the execution speed or completely stop the simulation at any given moment. Some of the parameters of the underlying physical models of the simulation can be modified at runtime. With the right settings for the parameters, some phenomena of molecular dynamics can be observed, for example the spacial structure of the molecules.
This thesis addresses the automated identification and localization of a time-varying number of objects in a stream of sensor data. The problem is challenging due to its combinatorial nature: If the number of objects is unknown, the number of possible object trajectories grows exponentially with the number of observations. Random finite sets are a relatively new theory that has been developed to derive at principled and efficient approximations. It is based around set-valued random variables that contain an unknown number of elements which appear in arbitrary order and are themselves random. While extensively studied in theory, random finite sets have not yet become a leading paradigm in practical computer vision and robotics applications. This thesis explores random finite sets in visual tracking applications. The first method developed in this thesis combines set-valued recursive filtering with global optimization. The problem is approached in a min-cost flow network formulation, which has become a standard inference framework for multiple object tracking due to its efficiency and optimality. A main limitation of this formulation is a restriction to unary and pairwise cost terms. This circumstance makes integration of higher-order motion models challenging. The method developed in this thesis approaches this limitation by application of a Probability Hypothesis Density filter. The Probability Hypothesis Density filter was the first practically implemented state estimator based on random finite sets. It circumvents the combinatorial nature of data association itself by propagation of an object density measure that can be computed efficiently, without maintaining explicit trajectory hypotheses. In this work, the filter recursion is used to augment measurements with an additional hidden kinematic state to be used for construction of more informed flow network cost terms, e.g., based on linear motion models. The method is evaluated on public benchmarks where a considerate improvement is achieved compared to network flow formulations that are based on static features alone, such as distance between detections and appearance similarity. A second part of this thesis focuses on the related task of detecting and tracking a single robot operator in crowded environments. Different from the conventional multiple object tracking scenario, the tracked individual can leave the scene and later reappear after a longer period of absence. Therefore, a re-identification component is required that picks up the track on reentrance. Based on random finite sets, the Bernoulli filter is an optimal Bayes filter that provides a natural representation for this type of problem. In this work, it is shown how the Bernoulli filter can be combined with a Probability Hypothesis Density filter to track operator and non-operators simultaneously. The method is evaluated on a publicly available multiple object tracking dataset as well as on custom sequences that are specific to the targeted application. Experiments show reliable tracking in crowded scenes and robust re-identification after long term occlusion. Finally, a third part of this thesis focuses on appearance modeling as an essential aspect of any method that is applied to visual object tracking scenarios. Therefore, a feature representation that is robust to pose variations and changing lighting conditions is learned offline, before the actual tracking application. This thesis proposes a joint classification and metric learning objective where a deep convolutional neural network is trained to identify the individuals in the training set. At test time, the final classification layer can be stripped from the network and appearance similarity can be queried using cosine distance in representation space. This framework represents an alternative to direct metric learning objectives that have required sophisticated pair or triplet sampling strategies in the past. The method is evaluated on two large scale person re-identification datasets where competitive results are achieved overall. In particular, the proposed method better generalizes to the test set compared to a network trained with the well-established triplet loss.
Das Ziel der vorliegenden Bachelorarbeit war die Untersuchung
verschiedener Methoden zur Ermittlung und Verbesserung der User
Experience eines Softwareproduktes einer mittelständigen Firma. Hierzu
wurde zunächst ein geeignetes Designkonzept und dazu passende Methoden
der Evaluation und des Testings ermittelt und dann auf das Produkt
angewendet. Mit dem Leitgedanken des User-Centered-Designs wurden
Methoden ausgewählt, welche die Nutzerinnen/Nutzer ins Zentrum der
Untersuchung stellten.
So konnte mit Hilfe der Nutzerinnen/Nutzer des Produktes
herausgefunden werden, wie die User-Experience ausfällt und wie diese
noch verbessert werden kann. In einer Fokusgruppe sind Prototypen für
die Verbesserung und Weiterentwicklung der Software entstanden.
Diese Bachelorarbeit ist sowohl für Sofwaredesignerinnen/-designer,
als auch für Studentinnen/Studenten der Mensch-Maschine-Kommunikation
interessant.