13 Zentrale Universitätseinrichtungen
Permanent URI for this collectionhttps://elib.uni-stuttgart.de/handle/11682/14
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Item Open Access Ein adaptierbares Rahmenwerk für die Annotation von Skalar- und Vektorfelddaten(2015) Thull, MarianDie manuelle Annotation von Skalar- und Vektorfelddaten zum Zwecke des überwachten maschinellen Lernens bedeutet einen hohen zeitlichen Aufwand. Zusätzlich verursachen die heute gängigen rechteckigen Selektionsregionen Ungenauigkeiten. Als Reaktion darauf wird ein System vorgestellt, das die Annotation mittels allgemeiner polygonaler Regionen ermöglicht. Es bietet die Möglichkeit, die Visualisierung der Skalar- bzw. Vektorfelder flexibel zu wechseln. Dazu wird ein entsprechendes Plugin-System realisiert. Ebenso ist es möglich, die Berechnungsmethode der Merkmalsvektoren schnell und einfach durch Plugins auszutauschen. Das Rahmenwerk unterstützt die Verwaltung von Annotationsprojekten. In Kombination mit dem Plugin-System für die Visualisierung der zu annotierenden Daten und die Generierung der Merkmalsvektoren ist ein flexibles und leistungsfähiges Rahmenwerk entstanden. Als theoretische Basis werden in dieser Arbeit einige maschinelle Lernverfahren und ihre Evaluation, Grundlagen der Merkmalsvektorkonstruktion und die Vektorfeldvisualisierung mit Line Integral Convolution eingeführt. Darauf folgt eine Beschreibung des entstandenen Systems und seine Auswertung, die den Vorteil der polygonalen Regionen gegenüber den Rechtecken belegen kann. Zum Schluss wird ein Ausblick auf mögliche Verbesserungen des Rahmenwerks gegeben.Item Open Access Affective Sonification(2023) Caycedo, NicolasDie Definition von Gefühle ist immer noch ein heftig diskutiertes Thema, zu dem neue Herausfindungen ständig ans Licht gebracht werden. Externe Reize spielen oft eine wichtige Role in unseren Gefühlen und können unsere Stimmung schwanken in noch nicht ganz verstandenen Arten. Gefühle und Affekt haben auch auf unsere kognitive Leistung und Interpretation von anderen Reizen einen Einfluss. Umfangreichende Forschung über die Einwirkung der Musik und Klänge auf Emotion ist ausgeführt gewesen. Im Bereich der Sonifikation sind Daten oft abstrakt durch nicht sofort erkannbare Klänge dargestellt. Wir versuchen eine Benutzerstudie und die dazu gehörige Werkzeuge zu entwürfen, mit der man besser verstehen kann, wie der Gehöraspek einer audiovisuelle Datendarstellung den Enmpfänger beeinflusst. Im Lauf des Projekts entwickeln wir eine Softwareapplikation, die Elemente des partizipativen Designs einbindet, um Laien bei der Erstellung eines Daten representierenden Schalles zu helfen. Wir führen eine Pilotstudie und legen den Grundstein einer vollwertigen zukünftigen Benutzerstudie. Dieses Dokument beschreibt unser Entwurfprozess, Herausforderungen, und Überlegungen durch die Plannung der Benutzerstudie und dazu gehörige Software.Item Open Access Animated scatter plot transitions(2022) Brandt, VincentIn this thesis we present a model for transitions between different 2D scatter plots of the same underlying multivariate data. We examine three types of transitions: linear interpolation, rotation, and spline paths. These are implemented in a TypeScript library for web-based applications. In the library, we also provide user interface components, and utilize them for an example application for interactive use of our model. To evaluate the different transitions, we conducted an online user study with 25 participants. We compared the effectiveness of each method for tracing points or clusters through the animation. Using a questionnaire, we also surveyed the perceived difficulty of the tasks, as well as the appeal of each method. In the study, we found most transitions perform similarly. When tracing points through an animation, users generally preferred flatter transitions similar to linear interpolation and achieved worse performance especially in a 3-stage 3D rotation transition. We also found two view changes to be the longest transition for comfortably tracking points. When tracing clusters through an animation, all transitions were similar, though in questionnaires the same three-stage rotation performed worse again.Item Open Access Augmented reality drum kit feedback visualization(2021) Lammert, JonasThis thesis explores several visualizations that aim to assist aspiring drummers with learning the drums using projector-based augmented reality technology. It aims to provide feedback on their training sessions when they do not have a professional teacher available. This feedback is projected directly onto the instrument, so the user does not have to transfer the information from e.g. a screen to their drums and can save cognitive resources. We give feedback in real-time and retrospectively. For the real-time feedback, we have to consider a visualization that keeps the information lightweight, to not divert too much attention away from playing the instrument, so we use simple encodings like color or a speedometer. For retrospective feedback, we use more complex visualizations like a pie chart. Our approach can give feedback on timing and dynamics of the played pattern. We evaluated our visualizations with three case studies, one that focuses on comparing the different visualizations, one that evaluates their efficiency in identifying errors, and one that investigates the influence of the visualization regarding errors made over time. We conclude that the visualizations help the user identify their errors, however, we did not have enough data to truly verify that they reduce errors in one’s performance over time, or if one visualization has a better performance than the others.Item Open Access Augmented visualization guidance for wire placement in timber fabrication(2021) Zhu, MarcoAugmented reality has become a broad area over time, which opens up many opportunities, also for industry. Nevertheless, digital solutions have not yet been used for some industrial applications. We focus on the use case “wire placement in timber fabrication”. The task here is to place and fix a cable along a certain route on a timber panel. However, there are several important factors and risks to consider that could cause the task to fail. Usability and efficiency play an essential role in optimally supporting use cases like this. Furthermore, we hope to make the task of this special industrial use case easier for workers by using augmented reality. For such an optimization, the design of a suitable visualization as part of the augmented reality system is indispensable. We constructed possible virtual representations for this use case and developed different suitable prototypes. Based on a user study, we compared the visualizations of these prototypes, evaluated their efficiency and user experience by measuring the workload, usability, task completion time, and determining error rates. By analyzing the developed visualization prototypes, a certain prototype proved to be optimal. With this, the route of the cable is shown as a path on the timber plate and displayed in color. The efficiency differences between this prototype and the other prototypes, supported by augmented reality, are not severe. The use of the augmented reality system turned out to be an essential enrichment. Compared to an equivalent system that is not supported by augmented reality, the developed augmented reality systems showed clear advantages. The suitability of this prototype has been checked and proven through a dry run. The task of the use case could be carried out successfully while the important factors and risks were also considered. The final fabrication has yet to be carried out.Item Open Access Bias in scatterplots(2025) Krestic, AmelPrior beliefs of viewers are a significant factor of bias when working with visualizations. This belief bias can easily be evoked by axis labels and context, leading to an influence on a viewers interaction with and analysis of said visualization. Even for low level visual analytic tasks, viewer beliefs show themselves as an influence, where one would otherwise hope viewers would be entirely objective. Through a user study, I show how belief triggering axis labels can influence a viewer’s correlation estimates of scatter plots when compared to the same plots with neutral X/Y labels. Viewers first reported their beliefs in six variable pairs that are used as labels later. The viewer’s baseline correlation estimates of plots with X/Y labels were gathered, and compared to the estimates of the same plots, but with belief triggering labels (i.e. Income/Happiness). When viewers believed in the relation of the variables, they increased their correlation estimates. Meanwhile when they believed them not to be related, they decreased their estimates. Further more, this effect extends to the viewer’s gaze behavior. Viewers with different belief strengths showed different levels of fixation on outliers, increasing or decreasing from their baseline dependent on belief strength. They also generally showed different shifts in attention distribution across the plots. The results reaffirm the possible effect of belief on even low level analytic tasks, and suggest an effect on viewer perception akin to selective attention or increased salience of features that align with existing belief. These findings can aid researchers working on visualizations techniques and dynamic visualization systems that aim to recognize and mitigate such cognitive biases.Item Open Access Compressed streaming of sparse images(2025) Heger, FrankaVirtual reality applications can use Multiplane Images (MPIs) to render their virtual scenes. Scenes rendered like this consist of multiple layers, each containing objects visible at its corresponding depth level. Since many depth layers can exist, the amount of data required to transmit even one frame of such a scene can be enormous. This work evaluates the gains in encoding speed and file size achieved by packing only the occupied regions of the layered sparse image into a virtual image and compressing these virtual image sequences using established video codecs such as H.264 and H.265, VP9, and AV1, with both hardware and software implementations, while maintaining decent visual quality. The different encoders are evaluated regarding their encoding speed, file size, and quality. This research suggests that the H.264 FFmpeg software encoder using a tile size of 64 provides the best trade-off among all assessed metrics.Item Open Access ConsumAcup : Entwicklung eines Anwendersystems zur Datenanalyse und Visualisierung(2023) Al-Taie, ZainabIm Rahmen dieser Bachelorarbeit wird ein Anwendersystem entwickelt, das für die digitale Kaffeeabrechnung und Ressourcenverwaltung konzipiert ist. Dieses System ermöglicht es, die Daten zum Kaffeekonsum am VISUS zu erfassen und auf anschauliche Weise zu visualisieren. Basierend auf der szenariobasierten Design-Methode wurde zunächst eine Nutzerstudie durchgeführt, um die Anforderungen an das System zu ermitteln. Diese bilden die Grundlage für die Entwicklung des Systems, um sicherzustellen, dass die entwickelte Anwendung die Bedürfnisse und Anforderungen der Benutzer erfüllt. Die technische Umsetzung von ConsumAcup erfolgt auf Basis eines Raspberry Pi 4, eines 5-Zoll-Touchdisplays und eines NFC-Moduls. Während der Entwicklung der Anwendung wurden Visualisierungen erstellt, die mithilfe von Qt-Charts und Matplotlib realisiert wurden. Schließlich wurden die entwickelten Visualisierungen einer umfassenden Evaluierung durch die Benutzer unterzogen.Item Open Access Development and analysis of a taxonomy for augmented reality in safety critical environments(2025) Kuhn, SilasAugmented reality (AR) genießt anhaltende Aufmerksamkeit. Die Fähigkeit, virtuelle Objekte in ein reales Umfeld einzubauen, lässt sich in einer Vielzahl von Einsatzgebieten nutzen. Diese reichen von Unterhaltung und Fahrassistenzsystemen bis hin zu industriellen Anwendungen, wie dem Bereich Mensch-Roboter-Interaktion. Durch die Produktion von besseren und verlässlicheren Head-Mounted Displays zeigt AR ebenfalls Potenzial genutzt zu werden, um die situationsbedingte Wahrnehmung und dadurch auch die Sicherheit des Nutzers zu steigern. Diese Arbeit untersucht Charakteristiken von AR Visualisierungen, welche den Nutzen haben, die situationsbedingte Sicherheit des Nutzers zu steigern. Dafür konstruierten wir eine Taxonomie auf Basis von 55 Artikeln, welche wir in fünf Dimensionen klassifizierten: (1) Zweck der Visualisierung, (2) Daten, (3) Visualisierungsmethode, (4) Anwendungsbereich und (5) Interaktion mit der Visualisierung. Auf Grundlage dieser Taxonomie haben wir Spezifikationen für mögliche Anwendungen erstellt, von welcher wir manche in einem Prototypen implementierten.Item Open Access Einfluss der Kugelanzahl auf die visuelle Hervorhebungstechnik HiveFive(2024) Schoger, JannikUm in der Virtuellen Realität (VR) Objekte mittels eines diegetischen Schwarms hervorzuheben, haben Lange et al. die HiveFive Methode entwickelt. Unser Ziel war es zu untersuchen, welche Auswirkungen eine Änderung der Anzahl der Kugeln aus denen der Schwarm besteht, nach sich ziehen würde. Dafür haben wir in Unity einen Versuchsaufbau entwickelt und anschließend eine Studie über die Crowdsourcing-Plattform Prolific durchgeführt. Wir haben dabei gefunden, dass die Zeit bis die Hervorhebung erkannt wird nur bis maximal zehn Kugeln signifikant sinkt und danach keine signifikanten Unterschiede aufweist, oder, im Fall von 13 Kugeln, wieder signifikant ansteigt. Die Anzahl an falsch erkannten Objekten ist von 3 auf 7 Kugeln signifikant gefallen, sonst haben wir keine signifikanten Unterschiede gefunden.Item Open Access Entwicklung eines SenseGlove-basierten Programms zur Erstellung und Manipulation von Molekülmodellen via VR(2020) Gebhardt, PatrickDas Ziel dieser Arbeit war die Entwicklung eines Molekülbaukastens für Virtual Reality (VR) mit der Nutzung der SenseGlove. Bei bisherigen Systemen fehlt durch die zweidimensionale Betrachtung der räumliche Aspekt, wobei die visuelle Erfassung der modellierten Objekte erschwert wird. Außerdem ist es bei gewöhnlichen PC Anwendungen nicht möglich die virtuellen Strukturen haptisch zu erfassen, wodurch die Kräfte zwischen den Atomen für den Nutzer nicht spürbar sind. Durch die Verwendung der SenseGlove soll dabei ein intuitives Greifen und Interagieren mit virtuellen Objekten möglich gemacht werden. Der VR Molekülbaukasten unterstützt alle nötigen Grundtransformationen, um Kohlenstoffmodelle zu erstellen. Dabei stellt er vereinfachte Formen der intermolekularen Kräfte dar. Die erstellten Modelle können nach dem Erstellen exportiert und wieder verwendet werden. In einer Studie wurde der entwickelte VR Molekülbaukasten mit anderen bereits bestehenden Systemen verglichen. Die Ergebnisse dieser Studie belegen, dass der VR Molekülbaukasten ein innovatives Programm ist, welches ein überdurchschnittliches Nutzerfeedback liefert. Verglichen mit einem Handbaukasten, bewegt sich der VR Molekülbaukasten in Sachen natürlicher Interaktion mit diesem auf einem Level. Zusätzlich enthält er sämtliche Vorteile eines PC Programms. Für den Prototypen bedeutet das, dass eine Weiterentwicklung in der Zukunft sinnvoll wäre. Durch das Feedback der Studienteilnehmer wurden bereits einige mögliche Richtungen aufgezeigt, in die sinnvolle Weiterentwicklungen stattfinden könnten. Eine denkbare Innovation wäre eine portable Version ohne SenseGlove. Jedoch erscheint das Hinzufügen von neuen Funktionen, wie beispielsweise einer Skalierungsmöglichkeit oder ein vollständiges Periodensystem an nutzbaren Atomen, als mindestens genauso sinnvoll.Item Open Access Exploring how personality affects perception of uncertainty visualization(2025) Aboulgadayel, OmarInterpreting uncertainty visualizations can be cognitively demanding, and individual differences, such as personality traits, may affect how people perceive such visualizations. While prior research has explored personality and cognitive load independently, few studies have investigated their combined influence on perception and decision-making in uncertainty visualizations. We conducted an experiment based on a wildfire evacuation task that compared textual and visual representations of uncertainty. Participants completed the NASA Task Load Index to assess perceived cognitive workload and a Big Five personality traits test to measure individual differences in personality. Consistent with prior findings, visual representations led to higher evacuation rates and faster decision times compared to textual representations. However, textual representations were associated with lower perceived cognitive workload. Personality traits significantly impacted decision-making behavior and perceived cognitive workload. Participants high in extraversion, neuroticism or openness were more likely to evacuate, while those high in agreeableness or conscientiousness were less likely to evacuate and tended to take more time to decide. Additionally, agreeableness and conscientiousness were positively correlated with perceived cognitive workload across all representations, whereas neuroticism and openness showed negative correlations, though only in certain representations. These findings offer new insights into how personality affects the perception and cognitive load in the context of uncertainty visualizations.Item Open Access Exploring interaction modalities for immersive analytics and situated visualization(2020) Gärtner, NiklasAlthough setups of immersive environments offer a vast quantity of interaction options, the typically used input devices lack the capability to perform complex interactions, such as creating text for programming, in a reliable, efficient, and mobile fashion. As a result, developers who wish to create applications for immersive environments in domains like immersive analytics (IA) and situated visualization (SV) that feature complex interactions are forced to find workarounds to this problem, such as using a mobility constricting classical keyboard, inhibiting their design possibilities. I replaced classical keyboards with an alternative – wearable keyboards, defining a domain-specific configuration for programming by creating a framework to map the inputs of wearable keyboard to the outputs required to easily create syntax of the programming language. This solution enables users to perform this type of complex interaction while moving about without being forced to visually or at least spatially register position of the classical keyboards input options.Item Open Access Exploring the need for inclusive avatar design(2022) Halach, TimThis thesis performs an initial exploration of the topic of avatars with disability. Therefore some related topics are explored, namely VR, avatars and the concepts of immersion, presence and embodiment. Further a survey is conducted to gauge peoples opinion on and thoughts about avatars with disability. Finally a study is conceptualised which aims to find how comfortable disabled people are with using avatars with disability and which reactions they get from others. The survey shows that participants were not opposed to the idea of providing avatars with disability for those who want them however they were more hesitant when asked if they themselves would use such avatars.Item Open Access External tracking for head-mounted displays(2024) Motzer, SimonIn many applications based on head-mounted displays (HMD), external devices are employed to identify and track specific objects within the surrounding environment. One such application is the tracking of faces within the surrounding environment. One potential benefit of this application is the development of user interfaces (UI) that adapt to the recognized faces. As most HMDs are equipped with a camera, it is feasible to integrate face recognition into the system. The Company Meta imposed restrictions on the functionality of the Quest 3’s camera for external developers, thereby precluding the use of the internal camera for facial recognition. In this work, a system was developed that utilizes a smartphone (Samsung Galaxy S24 Ultra), mounted on the Quest via a 3D-printed holder, to recognize faces within the surrounding environment. Subsequently, the positional data is transformed for the Quest to facilitate the optimal marking of the faces. In regard to data transmission, users may select either an Internet or Bluetooth connection. The results of the system are encouraging, demonstrating the successful recognition and transmission of faces. Nevertheless, the insufficient accuracy in certain instances when identifying faces represents a compelling motivation for the ongoing advancement of the system.Item Open Access Eye-tracking study: which experimental design is better suited for cognitive tasks?(2023) Amer, RamaDie Gestaltung eines Eye-Tracking-Experiments kann das Verhalten des Nutzers gegenüber den Stimuli beeinflussen. Daher ist das Design einer nicht-intrusiven Eye-Tracking-Studie wichtig, um die Interaktion des Nutzers mit den Stimuli zu verstehen, insbesondere bei kognitiv anspruchsvollen Aufgaben. In dieser Arbeit wurden verschiedene Alternativen des Studiendesigns und ihre Auswirkungen auf die kognitive Belastung der Teilnehmer untersucht. Es wurden fünf verschiedene Designs vorgestellt, vier davon präsentierten die Fragen in Textform, wobei die Reihenfolge der Präsentation von Bild und Frage variierte, und ein Design präsentierte die Fragen auditiv. Es wurde eine Studie durchgeführt, bei der die Teilnehmer für jedes Design die Aufgabe des Visual Question Answering (visuelle Frage Beantwortung) durchführten und die kognitive Last für jedes Design einzeln gemessen wurde. Die Studie ergab, dass die Reihenfolge der Präsentation von Bild und Frage einen signifikanten Einfluss auf die kognitive Belastung hatte, während das Medium, mit dem die Fragen präsentiert wurden, keinen hatte.Item Open Access General-relativistic polygon rendering(2020) Winterhalter, FelixGeneral relativistic visualization addresses optical effects in the realm of general relativity, such as bending of light around massive objects like black holes and stars, affecting the appearance of objects in their proximity. In this thesis, we propose a method for real-time relativistic visualization of triangle meshes in the proximity of black holes, based on polygon rendering and a precomputed table containing information about the distortion and apparent locations of points to a static observer. The visualization process is based on standard polygon rendering through the OpenGL pipeline, but we apply a subdivision to heavily distorted triangles to achieve more accurate results (approximating the curving of straight lines in proximity of a black hole). We consider a static observer with a freely rotating camera, as well as movable objects (considered ‘quasistatic’, i.e. movement itself does not impact appearance, only its location in space). Some results are compared with renders from the ray tracing software GeoVis and we provide additional example visualizations of different objects and scenarios, as well as benchmarks for both the visualization as well as the precomputation-step of our method.Item Open Access Generating 3D hedge mazes from base 2D maps(2025) Gaug, ChristopherHistorical sites, particularly intricate structures like garden mazes, often survive only as two-dimensional maps, leaving their immersive, three-dimensional nature lost to time. This thesis addresses the challenge of digital reconstruction by developing and evaluating a procedural pipeline for generating immersive 3D hedge mazes from 2D vector data for virtual reality (VR) applications. Focusing on the historic Labyrinth of Versailles, this work presents a comprehensive workflow that begins with parsing SVG map data and using it to procedurally generate a network of splines within Unreal Engine 5. These splines then guide the placement of high-fidelity, modular hedge assets. The system leverages modern rendering technologies, including the Nanite virtualized geometry system to handle complex foliage and the Lumen global illumination system for photorealistic lighting. The evaluation demonstrates that the procedural generation pipeline is significantly more efficient and geometrically faithful to the source material than manual creation methods. The final result is a high-performance VR application that successfully reconstructs the historical maze, allowing for natural and immersive exploration. This work serves as a proof-of-concept, showcasing how procedural techniques combined with advanced real-time rendering can effectively transform static historical records into engaging, interactive cultural heritage experiences.Item Open Access Generating 3D topiaries from base geometric shapes(2025) Kemmler, TobiasVirtual Reality (VR) is increasingly used to simulate real-world environments in immersive digital spaces. One notable application is VR tours, which enable users to explore historically and culturally significant sites-whether they still exist or have been lost-on demand. This thesis presents a method for generating topiaries based on arbitrarily complex 3D geometries. The system requires two primary inputs: a 3D model that defines the desired topiary shape, and an image of the leaf to be applied as surface detail. Leveraging Unreal Engine's Nanite technology, highly detailed leaf textures can be rendered with exceptional efficiency. This allows for the creation of topiaries that maintain visual fidelity even in performance-critical VR environments. The quality and performance of the generated results are evaluated through comparisons with real photographs and benchmark testing.Item Open Access Immersive visual analysis of cello bow movements(2022) Kohler, YannikTo support cellists in analyzing their interpretation of a musical piece and comparing it to others, this work presents and explores possibilities to visualize musical data and motion-captured bow movements in virtual reality. The presented prototype utilizes consumer VR technology and, optionally, the OptiTrack motion capture system to record a cellist’s playing, providing different visualizations that can be viewed in real time as well as played back from recorded data. In this thesis, we propose a one-by-one mapping of the 3D path of the bow, supported by various synchronized 2D line charts that are placed in virtual reality. We map motion features, audio features, and computed metrics to the color and width of the respective segments of the 2D and 3D lines. To evaluate the proposed design a user study with two domain experts was conducted, showing potential use of the design and providing us with ideas for future improvements, such as an extension to augmented reality.