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Vibrotactile feedback via body-worn vibrating belts is a common means of direction signalization - e.g. for navigational tasks. Consequently such feedback devices are used to guide blind or visually impaired people but can also be used to support other wayfinding tasks - for instance, guiding actors in virtual studio productions. Recent effort has been made to simplify this task by integrating vibrotactile feedback into virtual studio applications. In this work we evaluate the accuracy of an improved direction signalization technique, utilizing a body-worn vibrotactile belt with a limited number of tactors, and compare it to other work. The results from our user study indicate that it is possible to signalize different directions accurately, even with a small number of tactors spaced by 90°.
The audio design for virtual environments includes simulation of acoustical room properties besides specifing sound sources and sinks and their behavior. Virtual environments supporting room reverberation not only gain realism but also provide additional information to the user about surrounding space. Catching the different sound properties by the different spaces requires partitioning the space by the properties of aural spaces. We define soundscape and aural attributes as an application and multimedia content interface. Calculated data on an abstract level is sent to spatialization backends. Part of this research was the implementation of a device driver for the Roland Sound Space Processor. This device not only directionalizes sound sources, but also controls room effects like reverberation.
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.
Two high dynamic range HDR environments maps based on video streams from fish-eye lens cameras are used for generating virtual lights in a virtual set renderer. The task of realistic virtual light setup of scenes using captured environment maps might be eased as well as visual quality improves. We discuss the light setting problem for virtual studio tv productions which have mixed scenes of real objects, actors, virtual objects and virtual backgrounds. Benefits of hdr interactive light control are that the real light in the studio does not have to be remodeled and the artistic impression by using the light in the studio is also captured. An analysis of system requirements identifies technical challenges. We discuss the properties of a prototype system including test production.
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.
A chatspace was developed that allows conversation with 3D sound using networked streaming in a shared virtual environment. The system provides an interface to advanced audio features, such as a "whisper function" for conveying a confided audio stream. This study explores the use of spatial audio to enhance a user's experience in multiuser virtual environments.
In an information-rich Virtual Reality (VR) environment, the user is immersed in a world containing many objects providing that information. Given the finite computational resources of any computer system, optimization is required to ensure that the most important information is presented to the user as clearly as possible and in a timely fashion. In particular, what is desired are means whereby the perspicuity of an object may be enhanced when appropriate. An object becomes more perspicuous when the information it provides to the user becomes more readily apparent. Additionally, if a particular object provides high-priority information, it would be advantageous to make that object obtrusive as well as highly perspicuous. An object becomes more obtrusive if it draws attention to itself (or equivalently, if it is hard to ignore). This paper describes a technique whereby objects may dynamically adapt their representation in a user's environment according to a dynamic priority evaluation of the information each object provides. The three components of our approach are:
- an information manager that evaluates object information priority,
- an enhancement manager that tabulates rendering features associated with increasing object perspicuity and obtrusion as a function of priority, and
- a resource manager that assigns available object rendering resources according to features indicated by the enhancement manager for the priority set for each object by the information manager.
We consider resources like visual space (pixels), sound spatialization channels (mixels), MIDI/audio channels, and processing power, and discuss our approach applied to different applications. Assigned object rendering features are implemented locally at the object level (e.g., object facing the user using the billboard node in VRML 2.0) or globally, using helper applications (e.g., active spotlights, semi-automatic cameras).
Mixed reality telepresence is becoming an increasingly popular form of interaction in social and collaborative applications. We are interested in how created virtual spaces can be archived, mapped, shared, and reused among different applications. Therefore, we propose a decentralized blockchain-based peer-to-peer model of distribution, with virtual spaces represented as blocks. We demonstrate the integration of our system in a collaborative mixed reality application and discuss the benefits and limitations of our approach.
Distance and Room Effects Control for the PSFC, an Auditory Display using a Loudspeaker Array
(2000)
The Pioneer Sound Field Controller (PSFC), a loudspeaker array system, features realtime configuration of an entire sound field, including sound source direction, virtual distance, and context of simulated environment (room characteristics: room size and liveness) for each of two sound sources. In the PSFC system, there is no native parameter to specify the distance between the sound source and sound sink (listener) and also no function to control it directrly. This paper suggests the method to control virtual distance using basic parameters: volume, room size and liveness. The implementation of distance cue is an important aspect of 3D sounds. Virtual environments supporting room effects like reverberation not only gain realism but also provide additional information to users about surrounding space. The context switch of different aural attributes is done by using an API of the Sound Spatialization Framework. Therefore, when the sound sink move through two rooms, like a small bathroom and a large living room, the context of the sink switches and different sound is obtained.
Distance and Room Effects Control for the PSFC, an Auditory Display using a Loudspeaker Array
(2000)
The Pioneer Sound Field Controller (PSFC), a loudspeaker array system, features realtime configuration of an entire sound field,including sound source direction, virtual distance, and context of simulated environment (room characteristics: room size and liveness)for each of two sound sources. In the PSFC system, there is no native parameter to specify the distance between the sound source and sound sink (listener) and also no function to control it directrly. This paper suggests the method to control virtual distance using basic parameters: volume, room size and liveness. The implementation of distance cue is an important aspect of 3D sounds. Virtual environments supporting room effects like reverberation not only gain realism but also provide additional information to users about surrounding space. The context switch of different aural attributes is done by using an API of the Sound Spatialization Framework. Therefore, when the sound sink move through two rooms, like a small bathroom and a large living room, the context of the sink switches and different sound is obtained.
Design of a Helical Keyboard
(1996)
Inspired by the cyclical nature of octaves and helical structure of a scale (Shepard, '82 and '83), we prepared a model of a piano-style keyboard (prototyped in Mathematica), which was then geometrically warped into a left-handed helical configuration, one octave/revolution, pitch mapped to height. The natural orientation of upper frequency keys higher on the helix suggests a parsimonious left-handed chirality, so that ascending notes cross in front of a typical listener left to right. Our model is being imported (via the dxf file format) into (Open Inventor/)VRML, where it can be driven by MIDI events, realtime or sequenced, which stream is both synthesized (by a Roland Sound Module), and spatialized by a heterogeneous spatial sound backend (including the Crystal River Engineering Acoustetron II and the Pioneer Sound Field Control speaker-array System), so that the sound of the respective notes is directionalized with respect to sinks, avatars of the human user, by default in the tube of the helix. This is a work-in-progress which we hope to be fully functional within the next few months.
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.
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.
The late immersion of multi-touch sensitive displays enables the use of tangibles on multi-touch screens. There a several wide spread and/or sophisticated solutions to fulfill this need but they seem to have some flaws. One popular system at the time of writing is an overlay frame that can be placed on a normal display with the corresponding size. The frame creates a grid with infrared light emitting diodes. The disruption of this grid can be detected and messages with the positions are sent via usb to a connected computer. This system is quite robust in matters of ambient light insensitivity and also fast to calibrate. Unfortunately it is not created with the recognition of tangibles in mind and printed patterns can not be resolved. This article summarizes an attempt to create fiducials that are recognized by an infrared multi-touch frame as fingers. Those false fingers are checked by a software for known patterns. Once a known pattern (= fiducial) has been recognized its position and orientation are send with the finger positions towards the interactive software. The usability is tested with an example application where tangibles and finger touches are used in combination.
Education at the University of Aizu is focussed upon computer science. Besides being the subject matter of many courses, however, the computer also plays a vital role in the educational process itself, both in the distribution of instructional media, and in providing students with valuable practical experience. All students have unlimited access (24-hours-a-day) to individual networked workstations, most of which are multimedia-capable (even video capture is possible in two exercise rooms). Without software and content tailored for computer-aided instruction, the hardware becomes an expensive decoration. In any case, there is a need to better educate the instructors and students in the use of the equipment. In the interest of facilitating effective, collaborative use of network-based computers in teaching, this article explores the impact that a network environment can have on such activities. First, as a general overview, and to examine the motivation for the use of a network environment in teaching, this article reviews a range of different styles of collaboration. Then the article shows what kind of tools are available for use, within the context of what has come to be called Computer-Supported Cooperative Work (CSCW).
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.
Virtual sets have evolved from computer-generated, prerendered 2D backgrounds to realtime, responsive 3D computer graphics and are nowadays standard repertoire of broadcasting divisions. The graphics, which are combined with real video feed becoming moresophisticated, real looking and more responsive. We will look at the recent developments and suggest further developments like integration of spatial audio into the studio production and generating interactive media streams. Educational institutes recognize the demands of the rising media industry and established new courses on media technology like the Duesseldorf University of Applied Sciences.
Multi-user virtual reality is transforming towards a social activity that is no longer only used by remote users, but also in large-scale location-based experiences. Usage of realtime-tracked avatars in co-located business-oriented applications with a ”guide-user-scenario” is examined for user-related factors of Spatial Presence, Social Presence, User Experience and Task Load. A user study was conducted in order to compare both techniques of a realtime-tracked avatar and a non-visualised guide. Results reveal that the avatar-guide enhanced and stimulated communicative processes while facilitating interaction possibilities and creating a higher sense of mental immersion for users and engagement.
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.