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The PSFC, or Pioneer sound field control system, is a DSP-driven hemispherical 14-loudspeaker array, installed at the University of Aizu Multimedia Center. Collocated with a large screen rear-projection stereographic display the PSFC features realtime control of virtual room characteristics and direction of two separate sound channels, smoothly steering them around a configurable soundscape. The PSFC controls an entire sound field, including sound direction, virtual distance, and simulated environment (reverb level, room size and liveness) for each source. It can also configure a dry (DSP-less) switching matrix for direct directionalization. The PSFC speaker dome is about 14 m in diameter, allowing about twenty users at once to comfortably stand or sit near its sweet spot.
The PSFC, or Pioneer Sound Field Controller, is a DSP-driven hemispherical loudspeaker array, installed at the University of Aizu Multimedia Center. The PSFC features realtime manipulation of the primary components of sound spatialization for each of two audio sources located in a virtual environment, including the content (apparent direction and distance) and context (room characteristics: reverberation level, room size and liveness). In an alternate mode, it can also direct the destination of the two separate input signals across 14 loudspeakers, manipulating the direction of the virtual sound sources with no control over apparent distance other than that afforded by source loudness (including no simulated environmental reflections or reverberation). The PSFC speaker dome is about 10 m in diameter, accommodating about fifty simultaneous users, including about twenty users comfortably standing or sitting near its ``sweet spot,'' the area in which the illusions of sound spatialization are most vivid. Collocated with a large screen rear-projection stereographic display, the PSFC is intended for advanced multimedia and virtual reality applications.
Shadows in computer graphics are an important rendering aspect for spatial objects. For realtime computer applications such as games, it is essential to represent shadows as accurate as possible. Also, various tv stations work with virtual studio systems instead of real studio sets. Especially for those systems, a realistic impression of the rendered and mixed scene is important. One challenge, hence, is the creation of a natural shadow impression. This paper presents the results of an empirical study to compare the performance and quality of different shadow mapping methods. For this test, a prototype studio renderer was developed. A percentage closer filter (pcf) with a number of specific resolutions is used to minimize the aliasing issue. More advanced algorithms which generate smooth shadows like the percentage closer soft shadow (pcss) method as well as the variance shadow maps (vsm) method are analysed. Different open source apis are used to develop the virtual studio renderer, giving the benefit of permanent enhancement. The Ogre 3D graphic engine is used to implement the rendering system, benefiting from various functions and plugins. The transmission of the tracking data is accomplished with the vrpn server/client and the Intersense api. The different shadow algorithms are compared in a virtual studio environment which also casts real shadows and thus gives a chance for a direct comparison throughout the empirical user study. The performance is measured in frames per secon
In order to improve the interactivity between users and computers, recent technologies focus on incorporating gesture recognition into interactive systems. The aim of this article is to evaluate the effectiveness of using a Myo control armband and the Kinect 2 for recognition of gestures in order to interact with virtual objects in a weather report scenario. The Myo armband has an inertial measurement unit and is able to read electrical activity produced by skeletal muscles, which can be recognized as gestures, which are trained by machine learning. A Kinect sensor was used to build up a dataset which contains motion recordings of 8 different gestures and was also build up by a gesture training machine learning algorithm. Both input methods, the Kinect 2 and the Myo armband, were evaluated with the same interaction patterns in a user study, which allows a direct comparison and reveals benefits and limits of each technique.
In this paper we propose an integrated immersive augmented reality solution for a software tool supporting spacecraft design and verification. The spacecraft design process relies on expertise in many domains, such as thermal and structural engineering. The various subsystems of a spacecraft are highly interdependent and have differing requirements and constraints. In this context, interactive visualizations play an important role in making expert knowledge accessible. Recent immersive display technologies offer new ways of presenting and interacting with computer-generated content. Possibilities and challenges for spacecraft configuration employing these technologies are explored and discussed. A user interface design for an application using the Microsoft HoloLens is proposed. To this end, techniques for selecting a spacecraft component and manipulating its position and orientation in 3D space are developed and evaluated. Thus, advantages and limitations of this approach to spacecraft configuration are revealed and discussed.
Was ist eigentlich ein "UnSeminar"? Prof. Marmann aus dem Fachbereich Medien der Hochschule Düsseldorf erklärt in einem Interview mit dem Hochschulradio Düsseldorf sein Konzept für die Durchführung von Seminaren, das den Teilnehmerinnen und Teilnehmern sehr viel Freiheit in der (digitalen) Ausgestaltung der Themen bietet.
In Anlehnung an das Barcamp-Format, das auch "Unkonferenz" genannt wird, werden die Seminarthemen erst im Verlauf der Veranstaltung und durch Teilnehmenden entwickelt. Hierzu dienen mehrere Feedbackschleifen. Darüber hinaus kommen in den Unseminaren verschiedene digitale Technologien zur Organisation, zur Kommunikation und zur Kreation zum Einsatz, um en passant auch die Digitalkompetenz der Studierenden weiterzuentwickeln. So ist z.B. ein Multimedia-Abstract Bestandteil eines jeden Seminarbeitrages und die Seminarbeiträge selbst werden mit einem typischen Blogsystem ausgearbeitet. Alle Beiträge sind innerhalb des Fachbereichs für interessierte Studierende einsehbar, so dass Studierende auch von Kommilitonen lernen können.
An ISO 27001 compliant information security management system is difficult to create, due to the the limited support for system development and documentation provided in the standard. We present a structured analysis of the documentation and development requirements in the ISO 27001 standard. Moreover, we investigate to what extent existing security requirements engineering approaches fulfill these requirements. We developed relations between these approaches and the ISO 27001 standard using a conceptual framework originally developed for comparing security requirements engineering methods. The relations include comparisons of important terms, techniques, and documentation artifacts. In addition, we show practical applications of our results.
Considering legal aspects during software development is a challenging problem, due to the cross-disciplinary expertise required. The problem is even more complex for cloud computing systems, because of the international distribution, huge amounts of processed data, and a large number of stakeholders that own or process the data. Approaches exist to deal with parts of the problem, but they are isolated from each other. We present an integrated method for elicitation of legal requirements. A cloud computing online banking scenario illustrates the application of our methods. The running example deals with the problem of storing personal information in the cloud and based upon the BDSG (German Federal Data Protection Act). We describe the structure of the online banking cloud system using an existing pattern-based approach. The elicited information is further refined and processed into functional requirements for software development. Moreover, our method covers the analysis of security-relevant concepts such as assets and attackers particularly with regard to laws. The requirements artifacts then serve as inputs for existing patterns for the identification of laws relevant for the online banking cloud system. Finally, our method helps to systematically derive functional as well as security requirements that realize the previously identified laws.
The ISO 27000 is a well-established series of information security standards. The scope for applying these standards can be an organisation as a whole, single business processes or even an IT application or IT infrastructure. The context establishment and the asset identification are among the first steps to be performed. The quality of the results produced when performing these steps has a crucial influence on the subsequent steps such as identifying loss, vulnerabilities, possible attacks and defining countermeasures. Thus, a context analysis to gather all necessary information in the initial steps is important, but is not offered in the standard. In this paper, we focus on the scope of cloud computing systems and present a way to support the context establishment and the asset identification described in ISO 27005. A cloud system analysis pattern and different kinds of stakeholder templates serve to understand and describe a given cloud development problem, i.e. the envisaged IT systems and the relevant parts of the operational environment. We illustrate our support using an online banking cloud scenario.
This paper presents a mobile approach of integrating tangible user feedback in today’s virtual TV studio productions. We describe a tangible multitouch planning system, enabling a single user to prepare and customize scene flow and settings. Users can view and interact with virtual objects by using a tangible user interface on a capacitive multitouch surface. In a 2D setting created TV scenes are simultaneously rendered as separate view using a production/target renderer in 3D. Thereby the user experiences a closer reproduction of a final production and set assets can be reused. Subsequently, a user can arrange scenes on a timeline while maintaining different versions/sequences. The system consists of a tablet and a workstation, which does all application processing and rendering. The tablet is just an interface connected via wireless LAN.
Four Metamorphosis States in a Distributed Virtual (TV) Studio: Human, Cyborg, Avatar, and Bot
(2013)
The major challenge in virtual studio technology is the interaction between the actor and virtual objects. Within a distributed live production, two locally separated markerless tracking systems where used simultaneously alongside a virtual studio. The production was based on a fully tracked actor, cyborg (half actor, half graphics), avatar, and a bot. All participants could interact and throw a virtual disc. This setup is compared and mapped to Milgram’s continuum and technical challenges are described.
Cyberspatial audio applications are distinguished from the broad range of spatial audio applications in a number of important ways that help to focus this review. Most significant is that cyberspatial audio is most often designed to be responsive to user inputs. In contrast to non-interactive auditory displays, cyberspatial auditory displays typically allow active exploration of the virtual environment in which users find themselves. Thus, at least some portion of the audio presented in a cyberspatial environment must be selected, processed, or otherwise rendered with minimum delay relative to user input. Besides the technological demands associated with realtime delivery of spatialized sound, the type and quality of auditory experiences supported are also very different from those associated with displays that support stationary sound localization.
We give an enumeration of possible problem frames, based on domain characteristics, and comment on the usefulness of the obtained frames. In particular, we investigate problem domains and their characteristics in detail. This leads to fine-grained criteria for describing problem domains. As a result, we identify a new type of problem domain and come up with integrity conditions for developing useful problem frames. Taking a complete enumeration of possible problem frames (with at most three problem domains, of which only one is constrained) as a basis, we find 8 new problem frames, 7 of which we consider as useful in practical software development.
Virtual (tv) studios gain much more acceptance through improvements in computer graphics and camera tracking. Still commercial studios cannot have full interaction between actors and virtual scene because actors data are not completely digital available as well as the feedback for actors is still not sufficient. Markerless full body tracking might revolutionize virtual studio technology as it allows better interaction between real and virtual world. This article reports about using a markerless actor tracking in a virtual studio with a tracking volume of nearly 40 cubic meter enabling up to three actors within the green box. The tracking is used for resolving the occlusion between virtual objects and actors so that the Tenderer can output automatically a mask for virtual objects in the foreground in case the actor is behind. It is also used for triggering functions scripted within the Tenderer engine, which are attached to virtual objects, starting any kind of action (e.g., animation). Last but not least the system is used for controlling avatars within the virtual set. All tracking and rendering is done within a studio frame rate of 50 Hz with about 3 frames delay. The markerless actor tracking within virtual studios is evaluated by experts using an interview approach. The statistical evaluation is based on a questionnaire.
Live video broadcasting requires a multitude of professional expertise to enable multi-camera productions. Robotic systems allow the automation of common and repeated tracking shots. However, predefined camera shots do not allow quick adjustments when required due to unpredictable events. We introduce a modular automated robotic camera control and video switch system, based on fundamental cinematographic rules. The actors' positions are provided by a markerless tracking system. In addition, sound levels of actors' lavalier microphones are used to analyse the current scene. An expert system determines appropriate camera angles and decides when to switch from one camera to another. A test production was conducted to observe the developed prototype in a live broadcast scenario and served as a video-demonstration for an evaluation.
Live-Video-Broadcasting mit mehreren Kameras erfordert eine Vielzahl von Fachkenntnissen. Robotersysteme ermöglichen zwar die Automatisierung von gängigen und wiederholten Tracking-Aufnahmen, diese erlauben jedoch keine kurzfristigen Anpassungen aufgrund von unvorhersehbaren Ereignissen. In diesem Beitrag wird ein modulares, automatisiertes Kamerasteuerungs- und Bildschnitt-System eingeführt, das auf grundlegenden kinematografischen Regeln basiert. Die Positionen der Akteure werden durch ein markerloses Tracking-System bereitgestellt. Darüber hinaus werden Tonpegel der Lavaliermikrofone der Akteure zur Analyse der aktuellen Szene verwendet. Ein Expertensystem ermittelt geeignete Kamerawinkel und entscheidet, wann von einer Kamera auf eine andere umgeschaltet werden soll. Eine Testproduktion wurde durchgeführt, um den entwickelten Prototyp in einem Live-Broadcast-Szenario zu beobachten und diente als Videodemonstration für eine Evaluierung.
Die Interaktion zwischen Mensch und Computer ist ein sehr interessanter und immer wichtiger werdender Aspekt bei der Entwicklung von Software.
In diesem Buch erfahren Sie daher
- Wie Menschen und Computer kommunizieren, handeln und reagieren
- Welche Interaktionsformen es für die Kommunikation mit dem Computer gibt
- Wie Sie diese Kenntnisse nutzen können, um Programme zu entwickeln, die der Anwender erfolgreich nutzen kann
A mobile phone the size of a candy bar offers dozens of complex functions, a masterpiece of engineering. Unfortunately, the more functions are available, the less they are accessible to the average user. The design of the user interface suffers from a lack of suitability for the tasks, does not conform to user expectations and a suboptimal self-descriptiveness. The usability of modern mobile phones was tested in a broad survey with over 1300 participants. An internet based simulation offered tasks and an online evaluation. It could be pointed out that mobile phones are not only hard to access for novices but also those who consider themselves experts have difficulties when confronted with unknown functions or another brand of phone. Approaches to increase the usability are discussed.
Listening to music played by small MP3-players is almost as ubiquituous as talking over mobile phones. In this paper we analyse interaction elements and usabilty of current MP3-players. To determine the usability, an empirical study based on a website that presented three simulated MP3-players was performed with over 1000 participants.
The results show that, despite most marketing claims, some interaction devices are not as intuitive and really suitable for the task as they schould be. Also we found some surprising results concerning erroneous usage of navigation keys.
Based on experience in teaching programming, we developed the integrated development environment (IDE) 5Code especially to support beginners. As a first step, a simple, understandable formula was developed how to advance from the problem to the program in 5 operative steps:
read it → get it → think it → note it → code it.
In order to reduce the cognitive load of the learners effectively, 5Code was designed such that all 5 steps are permanently presented, accessible and executable. Thus, learners are provided with the entire programming context from presentation of the task via own notes and annotations to the code area. Learners can mark and annotate any part of the given task’s text; these annotations can be edited as notes with own comments. Furthermore, the notes can be dragged into the code area, where they are shown as comments in the coding language. Any modifications in the comments are synchronized between notes and code. 5Code is implemented as a web-application. It is used in university introductory courses on object oriented programming.
Es scheint so zu sein, dass sich die beiden Ziele Gebrauchstauglichkeit und Sicherheit sehr häufig in der Umsetzung gegenseitig ausschließen: Eine sehr sichere Anwendung ist meistens eher aufwändiger zu benutzen und zu warten, eine einfach zu benutzende Anwendung vernachlässigt häufig die Sicherheit.
Als Lösung kann (wieder einmal) darauf hingewiesen werden, dass "gute" Software mehr ist als lediglich funktionierende Software. Im gesamten Entwicklungsprozess müssen vielfältige funktionale und nicht-funktionale Anforderungen, wie die der Sicherheit und Gebrauchstauglichkeit, berücksichtigt werden, um allen, auch sich zunächst widersprechenden, Anforderungen gerecht zu werden.
Augmented reality for supporting manual non-destructive ultrasonic testing of metal pipes and plates
(2018)
We describe an application of augmented reality technology for non-destructive testing of products in the metal-industry. The prototype is created with hard- and software, that is usually employed in the gaming industry, and delivers positions for creating ultra- sonic material scans (C-scans). Using a stereo camera in combination with an hmd enables realtime visualisation of the probes path, as well as the setting of virtual markers on the specimen. As a part of the implementation the downhill simplex optimization algorithm is implemented to fit the specimen to a cloud of recorded surface points. The accuracy is statistically tested and evaluated with the result, that the tracking system is accurate up to ca. 1-2 millimeters in well set-up conditions. This paper is of interest not only for research institutes of the metal-industry, but also for any areas of work, in which the enhancement with augmented reality is possible and a precise tracking is necessary.
Classification of Beyond-Reality Interaction Techniques in Spatial Human-Computer Interaction
(2018)
The conductor's philosophy
(2013)
The Sound of Success: Investigating Cognitive and Behavioral Effects of Motivational Music in Sports
(2017)
Listening to music before, during, or after sports is a common phenomenon, yet its functions and effects on performance, cognition, and behavior remain to be investigated. Listening to music before, during, or after sports is a common phenomenon, yet its functions and effects on performance, cognition, and behavior remain to be investigated. In this study we present a novel approach to the role of music in sports and exercise that focuses on the notion of musical self-enhancement (Elvers, 2016). We derived the following hypotheses from this framework: listening to motivational music will (i) enhance self-evaluative cognition, (ii) improve performance in a ball game, and (iii) evoke greater risk-taking behavior. To evaluate the hypotheses, we conducted a between-groups experiment (N = 150) testing the effectiveness of both an experimenter playlist and a participant-selected playlist in comparison to a no-music control condition. All participants performed a ball-throwing task developed by Decharms and Davé (1965), consisting of two parts: First, participants threw the ball from fixed distances into a funnel basket. During this task, performance was measured. In the second part, the participants themselves chose distances from the basket, which allowed their risk-taking behavior to be assessed. The results indicate that listening to motivational music led to greater risk taking but did not improve ball-throwing performance. This effect was more pronounced in male participants and among those who listened to their own playlists. Furthermore, self-selected music enhanced state self-esteem in participants who were performing well but not in those who were performing poorly. We also discuss further implications for the notion of musical self-enhancement. // Listening to music before, during, or after sports is a common phenomenon, yet its functions and effects on performance, cognition, and behavior remain to be investigated. In this study we present a novel approach to the role of music in sports and exercise that focuses on the notion of musical self-enhancement (Elvers, 2016). We derived the following hypotheses from this framework: listening to motivational music will (i) enhance self-evaluative cognition, (ii) improve performance in a ball game, and (iii) evoke greater risk-taking behavior. To evaluate the hypotheses, we conducted a between-groups experiment (N = 150) testing the effectiveness of both an experimenter playlist and a participant-selected playlist in comparison to a no-music control condition. All participants performed a ball-throwing task developed by Decharms and Davé (1965), consisting of two parts: First, participants threw the ball from fixed distances into a funnel basket. During this task, performance was measured. In the second part, the participants themselves chose distances from the basket, which allowed their risk-taking behavior to be assessed. The results indicate that listening to motivational music led to greater risk taking but did not improve ball-throwing performance. This effect was more pronounced in male participants and among those who listened to their own playlists. Furthermore, self-selected music enhanced state self-esteem in participants who were performing well but not in those who were performing poorly. We also discuss further implications for the notion of musical self-enhancement.
This paper presents a conceptual framework for security engineering, with a strong focus on security requirements elicitation and analysis. This conceptual framework establishes a clear-cut vocabulary and makes explicit the interrelations between the different concepts and notions used in security engineering. Further, we apply our conceptual framework to compare and evaluate current security requirements engineering approaches, such as the Common Criteria, Secure Tropos, SREP, MSRA, as well as methods based on UML and problem frames. We review these methods and assess them according to different criteria, such as the general approach and scope of the method, its validation, and quality assurance capabilities. Finally, we discuss how these methods are related to the conceptual framework and to one another.
The interpretation process of complex data sets makes the integration of effective interaction techniques crucial. Recent work in the field of human-computer interaction has shown that there is strong evidence that multimodal user interaction, i.e. the integration of various input modalities and interaction techniques into one comprehensive user interface, can improve human performance when interacting with complex data sets. However, it is still unclear which factors make these user interfaces superior to unimodal user interfaces. The contribution of this work is an analytical comparison of a multimodal and a unimodal user interface for a scientific visualization application. We show that multimodal user interaction with simultaneously integrated speech and gesture input improves user performance regarding efficiency and ease of use.
This paper presents a tracking of parts of a human body in a virtual TV studio environment. The tracking is based on a depth camera and a HD studio camera and aims at a realistic interaction between the actor and the computer generated environment. Stereo calibration methods are used to match corresponding pixels of both cameras (HD color and depth image). Hence the images were rectified and column aligned. The disparity is used to correct the depth image pixel by pixel. This image registration results in row and column aligned images where ghost regions are in the depth image resulting from occlusion. Both images are used to generate foreground masks with chroma and depth keying. The color image is taken for skin color segmentation to determine and distinguish the actor’s hands and face. In the depth image the flesh colored regions were used to determine their spatial position. The extracted positions were augmented by virtual objects. The scene is rendered correctly with virtual camera parameters which were calculated from the camera calibration parameters. Generated computer graphics with alpha value are combined with the HD color images. This compositing shows interaction with augmented objects for verification. The additional depth information results in changing the size of objects next to the hands when the actor moves around.
Using spatial audio successfully for augmented reality (AR) applications is a challenge, but is awarded with an improved user experience. Thus, we have extended the AR/VR framework \sc Morgan with spatial audio to improve users orientation in an AR application. In this paper, we investigate the users’ capability to localize and memorize spatial sounds (registered with virtual or real objects). We discuss two scenarios. In the first scenario, the user localizes only sound sources and in the second scenario the user memorizes the location of audio-visual objects. Our results reflect spatial audio performance within the application domain and show which technology pitfalls still exist. Finally, we provide design recommendations for spatial audio AR environments.
In this paper we describe the design of a virtual reality simulator for traditional intuitive archery. Traditional archers aim without a target figure. Good shooting results require an excellent body-eye coordination that allows the user to perform identical movements when drawing the bow. Our simulator provides a virtual archery experience and supports the user to learn and practice the motion sequence of traditional archery in a virtual environment. We use an infrared tracking system to capture the user’s movements in order to correct his movement. To provide a realistic haptic feedback a real bow is used as interaction device. Our system provides a believable user experience and supports the user to learn how to shoot in the traditional way. Following a user-centered iterative design approach we developed a number of prototypes and evaluated them for refinement in sequent iteration cycles. For illustration purposes we created a short video clip in our virtual studio about this project that presents the main ideas in an informative yet entertaining way.