@inproceedings{BrettschneiderHerderdeMooijetal.2019, author = {Brettschneider, Nico and Herder, Jens and de Mooij, Jeroen and Ryskeldiev, Bektur}, title = {Audio vs. Visual Avatars as Guides in Virtual Environments}, series = {21th International Conference on Human and Computer, HC-2018, March 27-28, 2019, Shizuoka University, Hamamatsu, Japan.}, booktitle = {21th International Conference on Human and Computer, HC-2018, March 27-28, 2019, Shizuoka University, Hamamatsu, Japan.}, editor = {Herder, Jens}, publisher = {Hochschule D{\"u}sseldorf}, address = {D{\"u}sseldorf}, organization = {Hochschule D{\"u}sseldorf}, doi = {10.20385/0hrj-qc02}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-23859}, pages = {9}, year = {2019}, abstract = {Through constant technical progress, 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. We evaluate the usage of realtime-tracked avatars in co-located business-oriented applications in a "guide-user-scenario" in comparison to audio only instructions. The present study examined the effect of an avatar-guide on the user-related factors of Spatial Presence, Social Presence, User Experience and Task Load in order to propose design guidelines for co-located collaborative immersive virtual environments. Therefore, an application was developed and a user study with 40 participants was conducted in order to compare both guiding techniques of a realtime-tracked avatar guide and a non-visualised guide with otherwise constant conditions. 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. Furthermore, the avatar-guide appeared to make the storyline more engaging and exciting while helping users adapt to the medium of virtual reality. Even though no assertion could be made concerning the Task Load factor, the avatar-guide achieved a higher subjective value on User Experience. Due to the results, avatars can be considered valuable social elements in the design of future co-located collaborative virtual environments.}, language = {en} } @article{KuniiHerderMyszkowskietal.1994, author = {Kunii, Tosiyasu L. and Herder, Jens and Myszkowski, Karol and Okunev, Oleg and Okuneva, Galina and Ibusuki, Masumi}, title = {Articulation Simulation for an Intelligent Dental Care System}, series = {Displays}, volume = {15}, journal = {Displays}, number = {3}, pages = {181 -- 188}, year = {1994}, abstract = {CAD/CAM techniques are used increasingly in dentistry for design and fabrication of teeth restorations. An important issue is preserving occlusal contacts of teeth after restoration. Traditional techniques based on the use of casts with mechanical articulators require manual adjustment of occlusal surface, which becomes impractical when hard restoration materials like porcelain are used; they are also time and labor consuming. Most existing computer systems ignore completely such an articulation check, or perform the check at the level of a tooth and its immediate neighbors. We present a new mathematical model and a related user interface for global articulation simulation, developed for the Intelligent Dental Care System project. The aim of the simulation is elimination of the use of mechanical articulators and manual adjustment in the process of designing dental restorations and articulation diagnostic. The mathematical model is based upon differential topological modeling of the jawbs considered as a mechanical system. The user interface exploits metaphors that are familiar to dentists from everyday practice. A new input device designed specifically for use with articulation simulation is proposed.}, language = {en} } @inproceedings{RyskeldievCohenHerder2017, author = {Ryskeldiev, Bektur and Cohen, Michael and Herder, Jens}, title = {Applying rotational tracking and photospherical imagery to immersive mobile telepresence and live video streaming groupware}, series = {Proceeding SA '17 SIGGRAPH Asia 2017 Mobile Graphics \& Interactive Applications, Article No. 5}, booktitle = {Proceeding SA '17 SIGGRAPH Asia 2017 Mobile Graphics \& Interactive Applications, Article No. 5}, publisher = {ACM}, address = {New York}, isbn = {978-1-4503-5410-3}, doi = {10.1145/3132787.3132813}, pages = {2}, year = {2017}, abstract = {Mobile live video streaming is becoming an increasingly popular form of interaction both in social media and remote collaboration scenarios. However, in most cases the streamed video does not take mobile devices' spatial data into account (e.g., the viewers do not know the spatial orientation of a streamer), or use such data only in specific scenarios (e.g., to navigate around a spherical video stream).}, language = {en} } @inproceedings{Herder2001, author = {Herder, Jens}, title = {Applications of Spatial Auditory Displays in the Context of Art and Music}, series = {Human Supervision and Control in Engineering and Music}, booktitle = {Human Supervision and Control in Engineering and Music}, publisher = {Universit{\"a}t Kassel}, address = {Kassel}, year = {2001}, language = {en} } @article{AmanoMatsushitaYanagawaetal.1998, author = {Amano, Katsumi and Matsushita, Fumio and Yanagawa, Hirofumi and Cohen, Michael and Herder, Jens and Martens, William and Koba, Yoshiharu and Tohyama, Mikio}, title = {A Virtual Reality Sound System Using Room-Related Transfer Functions Delivered Through a Multispeaker Array: the PSFC at the University of Aizu Multimedia Center}, series = {TVRSJ}, volume = {3}, journal = {TVRSJ}, number = {1}, publisher = {J-STAGE}, doi = {10.18974/tvrsj.3.1_1}, pages = {1 -- 12}, year = {1998}, abstract = {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.}, language = {en} } @incollection{HerderMyszkowskiKuniietal.1996, author = {Herder, Jens and Myszkowski, Karol and Kunii, Tosiyasu L. and Ibusuki, Masumi}, title = {A Virtual Reality Interface to an Intelligent Dental Care System}, series = {Medicine Meets Virtual Reality 4}, booktitle = {Medicine Meets Virtual Reality 4}, editor = {Weghorst, Suzanne J. and Sieburg, Hans B. and Morgan, Karen S.}, publisher = {IOS Press}, address = {Amsterdam}, pages = {17 -- 20}, year = {1996}, language = {en} } @inproceedings{IshikawaHiroseHerder1998, author = {Ishikawa, Kimitaka and Hirose, Minefumi and Herder, Jens}, title = {A Sound Spatialization Server for a Speaker Array as an Integrated Part of a Virtual Environment}, series = {IEEE YUFORIC Germany 98}, booktitle = {IEEE YUFORIC Germany 98}, publisher = {IEEE}, address = {Stuttgart}, year = {1998}, abstract = {Spatial sound plays an important role in virtual reality environments, allowing orientation in space, giving a feeling of space, focusing the user on events in the scene, and substituting missing feedback cues (e.g., force feedback). The sound spatialization framework of the University of Aizu, which supports number of spatialization backends, has been extended to include a sound spatialization server for a multichannel loudspeaker array (Pioneer Sound Field Control System). Our goal is that the spatialization server allows easy integration into virtual environments. Modeling of distance cues, which are essential for full immersion, is discussed. Furthermore, the integration of this prototype into different applications allowed us to reveal the advantages and problems of spatial sound for virtual reality environments.}, language = {en} } @phdthesis{Herder1999, author = {Herder, Jens}, title = {A Sound Spatialization Resource Management Framework}, publisher = {University of Tsukuba}, address = {Tsukuba}, organization = {University of Tsukuba}, year = {1999}, abstract = {In a virtual reality environment, users are immersed in a scene with objects which might produce sound. The responsibility of a VR environment is to present these objects, but a practical system has only limited resources, including spatialization channels (mixels), MIDI/audio channels, and processing power. A sound spatialization resource manager, introduced in this thesis, controls sound resources and optimizes fidelity (presence) under given conditions, using a priority scheme based on psychoacoustics. Objects which are spatially close together can be coalesced by a novel clustering algorithm, which considers listener localization errors. Application programmers and VR scene designers are freed from the burden of assigning mixels and predicting sound source locations. The framework includes an abstract interface for sound spatialization backends, an API for the VR environments, and multimedia authoring tools.}, language = {en} } @article{HesseKoenigLogietal.1993, author = {Hesse, Jan and K{\"o}nig, Rainer and Logi, Filippo and Herder, Jens}, title = {A Prototype of an Interface Builder for the Common Lisp Interface Manager - CLIB}, series = {ACM Sigplan Notices}, volume = {28}, journal = {ACM Sigplan Notices}, number = {8}, publisher = {Forschungszentrum Informatik (FZI), Technical Expert Systems and Robotics}, doi = {10.1145/163114.163116}, pages = {19 -- 28}, year = {1993}, abstract = {The Common Lisp Interface Manager (CLIM) is used to develop graphical user interfaces for Lisp-basedapplications. With the prototype of the CLIM interface Builder (CLIB) the programmer can generate code for CLIM interactively. The developing process will be fast and less prone to errors. With this new tool, the interactive rapid prototyping reduces costs of a specification phase. Here we present the concept and first results of the prototype of CLIB.}, language = {en} } @inproceedings{PaulHerder2018, author = {Paul, Felix and Herder, Jens}, title = {A model-based filtering approach for real-time human motion data}, series = {Workshop Proceedings / Tagungsband: Virtuelle und Erweiterte Realit{\"a}t - 15. Workshop der GI-Fachgruppe VR/AR}, booktitle = {Workshop Proceedings / Tagungsband: Virtuelle und Erweiterte Realit{\"a}t - 15. Workshop der GI-Fachgruppe VR/AR}, editor = {Herder, Jens and Geiger, Christian and D{\"o}rner, Ralf and Grimm, Paul}, publisher = {Shaker Verlag}, address = {Herzogenrath}, isbn = {978-3-8440-6215-1}, doi = {10.2370/9783844062151}, pages = {37 -- 44}, year = {2018}, abstract = {Acquiring human motion data from video images plays an important role in the field of computer vision. Ground truth tracking systems require markers to create high quality motion data. But in many applications it is desired to work without markers. In recent years affordable hardware for markerless tracking systems was made available at a consumer level. Efficient depth camera systems based on Time-of-Flight sensors and structured light systems have made it possible to record motion data in real time. However, the gap between the quality of marker-based and markerless systems is high. The error sources of a markerless motion tracking pipeline are discussed and a model-based filter is proposed, which adapts depending on spatial location. The proposed method is then proven to be more robust and accurate than the unfiltered data stream and can be used to visually enhance the presence of an actor within a virtual environment in live broadcast productions.}, language = {en} }