This file was created by the TYPO3 extension publications --- Timezone: CEST Creation date: 2025-08-10 Creation time: 23:24:21 --- Number of references 27 All parts of an audio processing chain introduce latency. Previous studies have shown that high audio latency may negatively impact human performance in different scenarios, e.g., when performing live music or when interacting with real-time human-computer systems. However, is not yet known where the human perception threshold for audio latency lies, i.e., what the lowest amount of latency is that musicians might notice. Therefore, we conducted a user study (n=37) using the PEST method to estimate the just noticeable difference (JND) for audio latency under different base latency settings. Our results suggest that base latency influences the perception threshold in a non-linear manner: Participants achieved a mean JND of 49 ms for a base latency of 0 ms, 27 ms for a base latency of 64 ms, and 77 ms for a base latency of 512 ms. Furthermore, the JND was lower for participants with high musical sophistication. conference_item 2024 9 18 10.1145/3678299.3678331 Audio Mostly 2024 325-331 AM '24: Audio Mostly 2024 - Explorations in Sonic Cultures Milan, Italy https://epub.uni-regensburg.de/id/eprint/59003 Andreas Schmid Maria Ambros Johanna Bogon Raphael Wimmer Even though smartphones offer a broad design space for being used as input devices for video games, their form factor makes them less ergonomic than physical gamepads. Previous research suggests that customizable controller layouts and added haptic feedback can improve the quality of smartphone-based gamepads. However, there are no rigorous user studies comparing different types of smartphone controllers to each other. In this paper, we present results of a user study in which we compared three different smartphone-based gamepads: a smartphone controller with a standard layout, a customizable smartphone controller, and a smartphone controller with a haptic case. Additionally, we included a physical gamepad as a reference in our study. Participants used the different controllers to play a racing game and complete pointing tasks. We found that the physical gamepad outperforms smartphone-based controllers in terms of efficiency, but there was no significant difference in effectiveness. Furthermore, our qualitative findings open up design considerations for future improvements of smartphone-based game controllers. conference_item 2024 9 01 10.1145/3670653.3670676 207-218 MuC '24: Mensch und Computer 2024 Karlsruhe, Germany https://epub.uni-regensburg.de/id/eprint/58775 Christoph Wührl Andreas Schmid H??l Sabrina Raphael Wimmer People interact with a multitude of personal digital devices every day. However, transferring data between devices is still surprisingly cumbersome due to technical barriers, such as authentication or device pairing. Due to their clear affordances, physical devices offer a promising design space as mediators for natural interaction techniques. In a workshop and an elicitation study (n=30), we investigated different interaction techniques for cross-device data transfer using everyday objects. Our results suggest that depending on the use case, extending always-available physical objects might be more beneficial than developing new artifacts. Designing effective interaction techniques requires consideration of an artifact’s physical characteristics, affordances, and situational surroundings. Participants preferred multi-functional objects which are always at hand, such as their smartphone. However, they opted for more impersonal objects in unfamiliar situations. Interaction techniques associated with objects also influenced users' actions. We provide an overview of factors influencing intuitive interactions and we derived guidelines for user-centered development of interaction techniques with physical objects as mediators for data transfer. conference_item 2024 9 01 10.1145/3670653.3670778 242-255 MuC '24: Mensch und Computer 2024 Karlsruhe, Germany https://epub.uni-regensburg.de/id/eprint/58773 Martina Emmert Nicole Sch?nwerth Andreas Schmid Raphael Wimmer Christian Wolff Tables are focus points for social interactions and support everyday activities, such as learning, crafting, or dining. These physical interactions on and around the table may be augmented with digital information and tools projected onto the tabletop. For interaction with such projected information, touch input suffers from technical and interactional limitations. Pen input is a more robust alternative that does not suffer from Midas-touch problems. We developed a system for tracking the position of an IR-emitting pen tip on a planar surface with sub-millimeter resolution and an end-to-end latency of less than 30 ms. Distinguishing between drawing and hovering states is done by combining a stereoscopic camera setup and a machine-learning classifier. We demonstrate practical performance, uses and limitations through multiple studies and examples. book_section 2024 2 979-8-4007-0402-4 10.1145/3623509.3633366 TEI '24: Proceedings of the Eighteenth International Conference on Tangible, Embedded, and Embodied Interaction Association for Computing Machinery (ACM)

New York, United States

1-13 TEI '24: Eighteenth International Conference on Tangible, Embedded, and Embodied Interaction Cork Ireland 18 https://epub.uni-regensburg.de/id/eprint/55433 Vitus Maierh?fer Andreas Schmid Raphael Wimmer The latency of a text editor describes how long it takes from pressing a key to the corresponding letter appearing on the screen. It is well known that high latency affects how quickly authors can write and edit texts. In order to quantify the effects of latency on users’ performance and task load, we conducted a study in which 31 participants had to re-type or correct provided texts with a physical keyboard. Each participant completed each task once with a low latency of 20 ms and once with a high latency of 200 ms. We found that latency had no significant effect on users’ performance during the copy task, but correcting texts was affected significantly by high latency. Additionally, our results suggest that fast typers are more likely to notice latency than slow typers. Our findings regarding the effects of text input latency on users’ performance contributes to the existing body of research on latency in interactive systems. conference_item 2023 12 03 979-8-4007-0921-0 10.1145/3626705.3627784 Proceedings of the International Conference on Mobile and Ubiquitous Multimedia (MUM ’23) Association for Computing Machinery

New York, NY, USA

Florian Michahelles Pascal Knierim und Jonna H?kkil? 99-107 MUM '23: International Conference on Mobile and Ubiquitous Multimedia Vienna, Austria https://epub.uni-regensburg.de/id/eprint/55007 Andreas Schmid Michael Bierschneider Johannes Hoffmann Yu Liu Raphael Wimmer In interactive systems high latency affects user performance and experience. This is especially problematic in video games. A large number of studies on this topic investigated the effects of constant, high latency. However, in practice, latency is never constant but varies by up to 100 ms due to variations in processing time and delays added by polling between system components. In a large majority of studies, these variations in latency are neither controlled for nor reported. Thus, it is unclear to which degree small, continuous variations in latency affect user performance. If these unreported variations had a significant impact, this might cast into doubt the findings of some studies. To investigate how latency variation affects player performance and experience in games, we conducted an experiment with 28 participants playing a first-person shooter. Participants played with two levels of base latency (50 ms vs. 150 ms) and variation (0 ms vs. 50 ms). As expected, high base latency significantly reduces player performance and experience. However, we found strong evidence that small variations in latency in the order of 50 ms, do not affect player performance significantly. Thus, our findings mitigate concerns that previous latency studies might have systematically ignored a confounding effect. article 2023 10 10.1145/3611027 Proceedings of the ACM on Human-Computer Interaction 7 Association for Computing Machinery

New York, NY, USA

197-216 CHI PL https://epub.uni-regensburg.de/id/eprint/55003 Andreas Schmid David Halbhuber Thomas Fischer Raphael Wimmer Niels Henze Existing tools for screen sharing and remote control only allow a single user to interact with a system while others are watching. Collaborative editors and whiteboards allow multiple users to work simultaneously, but only offer a limited set of tools. With CoShare, we combine both concepts into a screen sharing tool that gives remote viewers a mouse pointer and a text cursor so that they can seamlessly collaborate within the same desktop environment. We have developed a proof-of-concept implementation that leverages Linux’ multi-pointer support so users can control applications in parallel. It also allows limited sharing of clipboard and dragging files from the remote viewer’s desktop into the video-streamed desktop. In focus groups we gathered user requirements regarding privacy, control, and communication. A qualitative lab study identified further areas for improvement and demonstrated CoShare’s utility. conference_item 2023 9 03 979-8-4007-0771-1 10.1145/3603555.3608524 MuC '23: Proceedings of Mensch und Computer 2023 Association for Computing Machinery

New York, United States

Markus Stolze Frieder Loch und Matthias Baldauf 325-329 MuC '23: Mensch und Computer 2023 Rapperswil Switzerland https://epub.uni-regensburg.de/id/eprint/54702 Martina Emmert Andreas Schmid Raphael Wimmer Niels Henze Prototyping interactive hardware artifacts is an iterative process that can produce significant amounts of waste. This problem becomes particularly apparent in teaching, when multiple students build the same artifact as an exercise and components can break when used improperly. In the context of a university course on tangible interaction, we explored how material found in the trash could be used as a resource for prototyping interactive artifacts. We could source interesting components and found that a bottom-up prototyping approach based on those components opened up new design spaces. Furthermore, as we relied on trash as a resource, we were able to considerably reduce waste during the course. conference_item 2023 9 03 10.18420/muc2023-mci-ws09-246 Mensch und Computer 2023 Rapperswil, Switzerland https://epub.uni-regensburg.de/id/eprint/54704 Andreas Schmid Alexander Kalus Raphael Wimmer People interact with a multitude of personal digital devices and infrastructural hardware every day. Oftentimes, they need to transfer data from one device to another. In many cases this process is still surprisingly cumbersome, requiring additional, non-intuitive steps, such as authentication, device pairing, or network setup. Tangible User Interfaces (TUIs) allow for quick and intuitive physical interaction with digital data. Therefore, they offer a promising design space towards more natural interaction techniques for cross-device data transfer. In a workshop and an elicitation study, we investigated different form factors and interaction techniques using six everyday objects in three different situations. We found that designing effective tangibles requires consideration of various factors which strongly depend on the target group and intended use case. conference_item 2023 9 03 10.18420/muc2023-mci-ws09-407 Mensch und Computer 2023 Rapperswil, Switzerland https://epub.uni-regensburg.de/id/eprint/54703 Martina Emmert Nicole Sch?nwerth Andreas Schmid Anton Ale?ik Raphael Wimmer Annotating and proof-reading documents are common tasks. Digital annotation tools provide easily searchable annotations and facilitate sharing documents and remote collaboration with others. On the other hand, advantages of paper, such as creative freedom and intuitive use, can get lost when annotating digitally. There is a large amount of research indicating that paper outperforms digital annotation tools in task time, error recall and task load. However, most research in this field is rather old and does not take into consideration increasing screen resolution and performance, as well as better input techniques in modern devices. We present three user studies comparing different annotation media in the context of proof-reading tasks. We found that annotating on paper is still faster and less stressful than with a PC or tablet computer, but the difference is significantly smaller with a state-of-the-art device. We did not find a difference in error recall, but the used medium has a strong influence on how users annotate. conference_item 2023 9 03 979-8-4007-0771-1 10.1145/3603555.3603572 MuC '23: Proceedings of Mensch und Computer 2023 Association for Computing Machinery

New York, United States

Markus Stolze Frieder Loch und Matthias Baldauf 277-288 MuC '23: Mensch und Computer 2023 Rapperswil Switzerland https://epub.uni-regensburg.de/id/eprint/54701 Andreas Schmid Marie Sautmann Vera Wittmann Florian Kaindl Philipp Schauhuber Philipp Gottschalk Raphael Wimmer Latency is an intrinsic property of all human-computer systems. As it can affect user experience and performance, it should be kept as low as possible for real-time applications. To identify the source of latency, measuring partial latencies is necessary. We present a new method for measuring the latency of graphics frameworks on X11-based systems. Our tool measures the time between an input event arriving at the kernel until a pixel is updated in graphics memory. In a systematic evaluation with 36 test applications, we found that our method delivers consistent results for most tested frameworks, and does not add a significant amount of additional end-to-end latency. Even though further investigation is required to explain inconsistencies with Qt-based frameworks, our method measures the latency of graphics frameworks reliably and accurately in all other cases. conference_item 2023 4 23 10.1145/3544549.3585779 Conference on Human Factors in Computing Systems 20233 Hamburg, Germany https://epub.uni-regensburg.de/id/eprint/54287 Andreas Schmid Raphael Wimmer Interactive tabletops do not only offer a large surface for collaborative interaction. They also offer quick access to digital tools directly at the table - where a large number of everyday activities take place. Tabletops with an embedded display are generally less flexible and more fragile than ordinary massive tabletops. Physical objects on the tabletop occlude the digital content. In contrast, top-down-projected interfaces using an overhead camera-projector system allow for augmenting arbitrary tables and the object lying on them. However, detecting pointing input only via a camera image captured from above requires robustly recognizing whether a finger or pen touches the tabletop or whether it hovers slightly above it. In this paper, we present a solution for reliably tracking a pen on arbitrary tabletop surfaces. The pen emits infrared light via a tip made of optical fiber. A camera captures position and shape of the light point on the surface. Our open-source tracking algorithm combines heuristics and a machine learning model to distinguish between drawing and hovering. A pilot study with 7 participants shows that that this system can be reliably used for drawing and writing on tabletops. However, occlusion by users’ hands can deteriorate tracking of the pen. conference_item 2022 9 04 10.18420/muc2022-mci-ws04-274 Mensch und Computer 2022 – Workshopband Gesellschaft für Informatik 15. Workshop Be-greifbare Interaktion Darmstadt https://epub.uni-regensburg.de/id/eprint/53135 Vitus Maierh?fer Andreas Schmid Raphael Wimmer Inside-out optical 2D tracking of tangible objects on a surface oftentimes uses a high-resolution pattern printed on the surface. While De-Bruijn-torus patterns offer maximum information density, their orientation must be known to decode them. Determining the orientation is challenging for patterns with very fine details; traditional algorithms, such as Hough Lines, do not work reliably. We show that a convolutional neural network can reliably determine the orientation of quasi-random bitmaps with 6 × 6 pixels per block within 36 × 36 pixel images taken by a mouse sensor. Mean error rate is below 2°. Furthermore, our model outperformed Hough Lines in a test with arbitrarily rotated low-resolution rectangles. This implies that CNN-based rotation-detection might also be applicable for more general use cases. article 2022 7 25 10.1145/3532719.3543259 Special Interest Group on Computer Graphics and Interactive Techniques Conference Posters Association for Computing Machinery https://epub.uni-regensburg.de/id/eprint/53134 Andreas Schmid Stefan Lippl Raphael Wimmer Despite ever improving digital ink and paper solutions, many people still prefer printing out documents for close reading, proofreading, or filling out forms. However, in order to incorporate paper-based annotations into digital workflows, handwritten text and markings need to be extracted. Common computer-vision and machine-learning approaches require extensive sets of training data or a clean digital version of the document. We propose a simple method for extracting handwritten annotations from laser-printed documents using multispectral imaging. While black toner absorbs infrared light, most inks are invisible in the infrared spectrum. We modified an off-the-shelf flatbed scanner by adding a switchable infrared LED to its light guide. By subtracting an infrared scan from a color scan, handwritten text and highlighting can be extracted and added to a PDF version. Initial experiments show accurate results with high quality on a test data set of 93 annotated pages. Thus, infrared scanning seems like a promising building block for integrating paper-based and digital annotation practices. conference_item 2022 4 29 10.1145/3491101.3519872 Association for Computing Machinery Art. no. 363 CHI Conference on Human Factors in Computing SystemsExtended Abstracts (CHI ’22 Extended Abstracts) New Orleans, LA, USA https://epub.uni-regensburg.de/id/eprint/53129 Andreas Schmid Lorenz Heckelbacher Raphael Wimmer We demonstrate usage examples and technical properties of Dothraki, an inside-out tracking technique for tangibles on flat surfaces. An optical mouse sensor embedded in the tangible captures a small (36×36 pixel / 1×1 mm), unique section of a black-and-white De-Bruijn dot pattern printed on the surface. Our system efficiently searches the pattern space in order to determine the precise location of the tangible with sub-millimeter accuracy. Our proof-of-concept implementation offers a recognition rate of up to 95%, robust error detection, an update rate of 14 Hz, and a low-latency relative tracking mode. The MuC demonstration encompasses four separate demos that showcase typical application scenarios and features: a magic lens, two tangibles that know each others relative position, a simple geometry application that measures distances and angles, and tangibles that know on which of multiple surfaces they have been placed. conference_item 2021 9 05 10.1145/3473856.3474030 Mensch und Computer 2021 (MuC ’21) Ingolstadt, Germany https://epub.uni-regensburg.de/id/eprint/47827 Dennis Schüsselbauer Andreas Schmid Raphael Wimmer Taking screenshots is a common way of capturing screen content to share it with others or save it for later. Even though all major desktop operating systems come with a screenshot function, a lot of people also use smartphone cameras to photograph screen contents instead. While users see this method as faster and more convenient, image quality is significantly lower. This paper is a demonstration of ScreenshotMatcher, a system that allows for capturing a high-fidelity screenshot by taking a smartphone photo of (part of) the screen. A smartphone application sends a photo of the screen region of interest to a program running on the PC which retrieves the corresponding screen region with a feature matching algorithm. The result is sent back to the smartphone. As phone and PC communicate via WiFi, ScreenshotMatcher can also be used together with any PC in the same network running the application - for example to capture screenshots from a colleague's PC. Released as open-source code, ScreenshotMatcher may be used as a basis for applications and research prototypes that bridge the gap between PC and smartphone. conference_item 2021 9 05 10.1145/3473856.3474029 Mensch und Computer 2021 (MuC ’21) Ingolstadt, Germany https://epub.uni-regensburg.de/id/eprint/47825 Andreas Schmid Thomas Fischer Alexander Weichart Alexander Hartmann Raphael Wimmer Taking screenshots is a common way of capturing screen content to share it with others or save it for later. Even though all major desktop operating systems come with a screenshot function, a lot of people also use smartphone cameras to photograph screen contents instead. While users see this method as faster and more convenient, image quality is significantly lower. With ScreenshotMatcher, we present a system that allows for capturing a high-fidelity screenshot by taking a smartphone photo of (part of) the screen. A smartphone application sends a photo of the screen region of interest to a program running on the PC which retrieves the matching screen region and sends it back to the smartphone. Comparing four feature matching algorithms and multiple parameters, we identified a combination of ORB keypoint detection (feature limit 2000) and a brute force feature matcher using Hamming distance as the best solution for this task (success rate: 85%, processing time: 90 ms). This raw performance results in a real-world success rate of 47% and a mean response time per screenshot of 878 ms as measured in a remote user study (N=19). Released as open-source code, ScreenshotMatcher may be used as a basis for applications and research prototypes that bridge the gap between PC and smartphone. conference_item 2021 9 05 978-1-4503-8645-6 10.1145/3473856.3474014 MuC '21: Proceedings of Mensch und Computer 2021 Proceedings of the Mensch und Computer 2021 Association for Computing Machinery

New York, United States

Stefan Schneegass und Bastian Pfleging 44-48 Mensch und Computer 2021 (MuC ’21) Ingolstadt, Germany https://epub.uni-regensburg.de/id/eprint/47814 Andreas Schmid Thomas Fischer Alexander Weichart Alexander Hartmann Raphael Wimmer End-to-end latency - the time a computer system needs from an input event until output is displayed - directly influences task difficulty and user experience. It is therefore an important topic in HCI research. Different human-computer interfaces require different ways to measure latency as it is influenced by all involved hardware and software components. However, many approaches to measuring latency rely on professional lab equipment and are therefore hard to replicate. We propose a method for accurately measuring the end-to-end latency of traditional setups with a button-equipped input device and a display. To this end, a microcontroller closes the electrical contact of a mouse button to trigger an input event, and captures the screen response via a photo-resistor. Our approach combines parts of different existing methods to measure latency and only relies on cheap and off-the-shelf components to allow for easy replication. The latency values measured by our device are very close to those measured with a high-speed smartphone camera (240 Hz). The maximum error is below 2.64 ms - lower than the camera's temporal resolution and the screen refresh periods of high-fps computer displays. Therefore, our approach allows for repeatedly and reliably measuring end-to-end-latency. conference_item 2021 5 08 10.31219/osf.io/tkghj EHPHCI: Esports and High Performance HCI Yokohama, Japan https://epub.uni-regensburg.de/id/eprint/45570 Andreas Schmid Raphael Wimmer Tangibles are small, graspable objects that act as input devices or physical representations of digital data. Oftentimes, it is desirable to track the position of tangibles on a surface and their relation to each other. However, outside-in tracking techniques - such as capacitive touchscreens or cameras - require setting up elaborate infrastructure and are prone to occlusion or interference. We propose Dothraki, an inside-out tracking technique for tangibles on flat surfaces. An optical mouse sensor embedded in the tangible captures a small (36×36 pixel / 1×1 mm), unique section of a black-and-white De-Bruijn dot pattern printed on the surface. Our system efficiently searches the pattern space in order to determine the precise location of the tangible with sub-millimeter accuracy. Our proof-of-concept implementation offers a recognition rate of up to 95%, robust error detection, an update rate of 14 Hz, and a low-latency relative tracking mode. conference_item 2021 2 15 978-1-4503-8213-7 10.1145/3430524.3440656 TEI '21: Proceedings of the Fifteenth International Conference on Tangible, Embedded, and Embodied Interaction Association for Computing Machinery

New York, United States

und 1-10 TEI '21: Fifteenth International Conference on Tangible, Embedded, and Embodied Interaction Salzburg 37 https://epub.uni-regensburg.de/id/eprint/44868 Dennis Schüsselbauer Andreas Schmid Raphael Wimmer The latency of a computing system affects users' performance. One important component of end-to-end latency is display lag - the time required to turn framebuffer contents into photons emitted by a computer screen. However, there is no well-documented and widely available method for measuring display lag.Thus, the effect of display lag is rarely considered in scientific studies and system development. We developed DispLagBox, a simple open-source device for measuring display lag. It supports the International Display Measurements Standard but also offers additional metrics for characterizing display lag with a resolution of 0.1 ms. The device, based on a Raspberry Pi computer, measures the time between VSYNC and a change in brightness on the connected display. Repeated measurements can be conducted automatically, so that not only average latency but also latency distributions for each device can be reported. For most displays we tested, DispLagBox reports latencies that are close to those reported by a commercial black-box measurement device. Typically, the difference is 1 - 3 ms. conference_item 2020 9 06 978-1-4503-7540-5 10.1145/3404983.3410015 MuC '20: Proceedings of Mensch und Computer 2020 Association for Computing Machinery

New York, United States

Bernhard Preim Andreas Nürnberger und Christian Hansen 105-108 MuC '20: Proceedings of Mensch und Computer 2020 Magdeburg Germany https://epub.uni-regensburg.de/id/eprint/43695 Patrick Stadler Andreas Schmid Raphael Wimmer Sketching with Hardware is an undergraduate university course with the goal to teach students how to build prototypes for tangible user interfaces. Goals of this course are to create awareness for tangible interaction among students and prepare them to realize advanced projects like bachelor's and master's theses in this field. In this paper, authors share their experience teaching the concepts of tangible interaction, electronics and prototyping to computer science students in a two week course. The course's content, structure and goals are explained, and needed material and infrastructure are described. The long-term effect of the course has been evaluated by conducting a survey among former participants. conference_item 2019 9 08 10.18420/muc2019-ws-563 Mensch und Computer 2019 Hamburg https://epub.uni-regensburg.de/id/eprint/40681 Andreas Schmid Raphael Wimmer Sensornetzwerke sind ein wichtiges Werkzeug um Daten über die Umwelt zu sammeln, jedoch müssen sie oft an einen bestimmten Anwendungsfall angepasst werden, wofür fortgeschrittene Kenntnisse in der Programmierung vonn?ten sind. Da Sensornetzwerke h?ufig in der ?kologie, der Geologie oder für die Heimautomatisierung eingesetzt werden, haben viele ihrer AnwenderInnen nicht die dafür ben?tigten Programmierkenntnisse. Aus diesem Grund wurde in dieser Arbeit ein Sensornetzwerk mit einer dazugeh?rigen Programmierschnittstelle erstellt, die sich durch starke Abstrahierung von technischer Komplexit?t speziell an AnwenderInnen mit geringen Programmierkenntnissen richtet. Anforderungen an die Schnittstelle wurden durch eine ausführliche Literaturrecherche und einer Fokusgruppenstudie erhoben. Nach der Implementierung wurde die Benutzbarkeit der Programmierschnittstelle in einer Nutzerstudie evaluiert und mit einem ?hnlichen System verglichen. Das Sensornetzwerk wurde in Feldexperimenten auf seine praxistauglichkeit untersucht. thesis_rgbg 2019 7 18 https://epub.uni-regensburg.de/id/eprint/40502 Andreas Schmid book_section 2019 5 04 978-1-4503-5970-2 10.1145/3290605.3300650 CHI '19 Proceedings of the 2019 CHI Conference on Human Factors in Computing Systems Paper No. 420 ACM

New York, NY, USA

420:1-420:12 https://epub.uni-regensburg.de/id/eprint/40182 Raphael Wimmer Andreas Schmid Florian Bockes We demonstrate a simple technique that allows tangible objects to track their own position on a surface using an off-the-shelf optical mouse sensor. In addition to measuring the (relative) movement of the device, the sensor also allows capturing a low-resolution raw image of the surface. This makes it possible to detect the absolute position of the device via marker patterns at known positions. Knowing the absolute position may either be used to trigger actions or as a known reference point for tracking the device. This demo allows users to explore and evaluate affordances and applications of such tangibles. conference_item 2018 10 13 10.1145/3267782.3274690 Symposium on Spatial User Interaction 2018 Berlin https://epub.uni-regensburg.de/id/eprint/47826 Dennis Schüsselbauer Andreas Schmid Raphael Wimmer Laurin Muth Tangible User Interfaces (TUIs) integrieren oft physische Objekte, deren Positionierung oder Positionsver?nderung durch den Nutzer zur Interaktion verwendet wird. DotTrack ist ein Tracking-Verfahren, das absolute Ortsbestimmung und Tracking der Position von Tangibles ohne externe Infrastruktur erlaubt. Der Prototyp verwendet dazu einen kommerziellen Maussensor, der nicht nur die Translation misst, sondern auch ein Kamerabild des Untergrunds liefert. Ein eindeutiges Punktmuster auf dem Untergrund erlaubt es, die absolute Position des Prototypen zu bestimmen. Im momentanen Entwicklungsstand sind rudiment?re absolute Ortsbestimmung, Positionstracking und mehrere Anwendungsbeispiele für das System implementiert. conference_item 2018 9 02 10.18420/muc2018-ws05-0500 Mensch und Computer 2018 Dresden https://epub.uni-regensburg.de/id/eprint/37581 Dennis Schüsselbauer Andreas Schmid Raphael Wimmer Laurin Muth High latency in an interactive system limits its usability. In order to reduce end-to-end latency of such systems, it is necessary to analyze and optimize the latency of individual contributors, such as input devices, applica-tions, or displays. We present a simple tool for measur-ing the latency of USB-connected input devices with sub-millisecond accuracy. The tool, based on a Rasp-berry Pi 2 microcomputer, repeatedly toggles a button of a game controller, mouse, or keyboard via an opto-coupler soldered to the button and measures the time until the input event arrives. This helps researchers, developers and users to identify and characterize sources of input lag. An initial comparison of multiple input devices shows differences not only in average latency but also in its variance. conference_item 2018 1 15 CHI 2018 Montreal, Canada https://epub.uni-regensburg.de/id/eprint/36811 Florian Bockes Raphael Wimmer Andreas Schmid In the field of pedestrian navigation some systems use prominent identifying features, so called landmarks. Attributes of high-quality landmarks are recognizability, actuality, uniqueness and noticeability. One of the challenges of this kind of navigation systems is to collect and evaluate landmarks with consistent quality. The system we developed solves these struggles with a crowdsourcing approach. We combine this with gamification elements in order to reach many users and to assure long-term motivation. Our system shows images of existing landmarks to the player, which he is afterwards asked to assign to a map of the university. Depending on the distance of his guess to the real position the player earns points. The application strives to encourage users to upload and rate pictures of existing landmarks. A multiplayer mode which allows challenging other users keeps them involved. In contrast to other products, our system does not rely on localization via GPS. Another goal was to implement a self-running system with a minimal amount of dedicated administration needed. Therefore the users with the highest scores are rating the submitted content. conference_item 2015 10.1145/2836041.2841209 ACM

New York, NY, USA

364-367 14th International Conference on Mobile and Ubiquitous Multimedia Linz, Austria https://epub.uni-regensburg.de/id/eprint/36661 Florian Bockes Laura Edel Matthias Ferstl Andreas Schmid