VR Based Visualization and Exploration of Plant Biological Data

This paper investigates the use of virtual reality (VR) technologies to facilitate the analysis of plant biological data in distinctive steps in the application pipeline. Reconstructed three-dimensional biological models (primary polygonal models) transferred to a virtual environment support scientists' collaborative exploration of biological datasets so that they obtain accurate analysis results and uncover information hidden in the data. Examples of the use of virtual reality in practice are provided and a complementary user study was performed.

Simulations- und VR-basierte Steuerungsverifikation zellularer Intralogistiksysteme

Die hohe Komplexität zellularer intralogistischer Systeme und deren Steuerungsarchitektur legt die Verwendung moderner Simulations- und Visualisierungstechniken nahe, um schon im Vorfeld Aussagen über die Leistungsfähigkeit und Zukunftssicherheit eines geplanten Systems treffen zu können. In dieser Arbeit wird ein Konzept für ein Simulationssystem zur VR-basierten Steuerungsverifikation zellularer Intralogistiksysteme vorgestellt. Beschrieben wird die Erstellung eines Simulationsmodells für eine real existierende Anlage und es wird ein Überblick über die Bestandteile der Simulation, insbesondere die Anbindung der Steuerung des realen agentenbasierten Systems, gegeben.

Ermittlung der Leistungsverfügbarkeit zellularer Intralogistiksysteme mit Hilfe von Simulations- und VR-Techniken

Die Bestimmung der Leistungsverfügbarkeit als Maß für den Erfüllungsgrad logistischer Prozesse erfolgt gewöhnlich während des Betriebes einer logistischen Anlage. Wir haben ein Simulationssystem entwickelt, um die Leistungsverfügbarkeit einer zellularen intralogistischen Anlage schon im Vorfeld ermitteln zu können. Die detailgenaue Simulation erfasst dabei nicht nur Einflüsse statischer Parameter wie Dimensionierung der Anlage sondern auch dynamische Parameter, wie Fahrzeugverhalten oder Auftragszusammensetzung. Aufgrund der Echtzeit- und VR-Fähigkeit des vorgestellten Systems, ist eine Präsentation in einer VR-Umgebung möglich. Intuitive Interaktionsmechanismen und Visualisierungs-Metaphern bieten einen intuitiven Zugang zur Leistungsverfügbarkeit des Systems und den Größen, die sie beeinflussen.

Automatic Data Normalization and Parameterization for Optical Motion Tracking

Methods for optical motion capture often require timeconsuming manual processing before the data can be used for subsequent tasks such as retargeting or character animation. These processing steps restrict the applicability of motion capturing especially for dynamic VR-environments with real time requirements. To solve these problems, we present two additional, fast and automatic processing stages based on our motion capture pipeline presented in [HSK05]. A normalization step aligns the recorded coordinate systems with the skeleton structure to yield a common and intuitive data basis across different recording sessions. A second step computes a parameterization based on automatically extracted main movement axes to generate a compact motion description. Our method does not restrict the placement of marker bodies nor the recording setup, and only requires a short calibration phase.

MHP Oriented Interactive Augmented Reality System for Sports Broadcasting Environments

Television and movie images have been altered ever since it was technically possible. Nowadays embedding advertisements, or incorporating text and graphics in TV scenes, are common practice, but they can not be considered as integrated part of the scene. The introduction of new services for interactive augmented television is discussed in this paper. We analyse the main aspects related with the whole chain of augmented reality production. Interactivity is one of the most important added values of the digital television: This paper aims to break the model where all TV viewers receive the same final image. Thus, we introduce and discuss the new concept of interactive augmented television, i. e. real time composition of video and computer graphics - e.g. a real scene and freely selectable images or spatial rendered objects - edited and customized by the end user within the context of the user's set top box and TV receiver.

Augmenting a Laser Pointer with a Diffraction Grating for Monoscopic 6DOF Detection

This article illustrates the detection of 6 degrees of freedom (DOF) for Virtual Environment interactions using a modified simple laser pointer device and a camera. The laser pointer is combined with a diffraction rating to project a unique laser grid onto the projection planes used in projection-based immersive VR setups. The distortion of the projected grid is used to calculate the translational and rotational degrees of freedom required for human-computer interaction purposes.

Evaluation of Binocular Eye Trackers and Algorithms for 3D Gaze Interaction in Virtual Reality Environments

Tracking user’s visual attention is a fundamental aspect in novel human-computer interaction paradigms found in Virtual Reality. For example, multimodal interfaces or dialogue-based communications with virtual and real agents greatly benefit from the analysis of the user’s visual attention as a vital source for deictic references or turn-taking signals. Current approaches to determine visual attention rely primarily on monocular eye trackers. Hence they are restricted to the interpretation of two-dimensional fixations relative to a defined area of projection. The study presented in this article compares precision, accuracy and application performance of two binocular eye tracking devices. Two algorithms are compared which derive depth information as required for visual attention-based 3D interfaces. This information is further applied to an improved VR selection task in which a binocular eye tracker and an adaptive neural network algorithm is used during the disambiguation of partly occluded objects.

Spatial audition in a static virtual environment : the role of auditory-visual interaction

The integration of the auditory modality in virtual reality environments is known to promote the sensations of immersion and presence. However it is also known from psychophysics studies that auditory-visual interaction obey to complex rules and that multisensory conflicts may disrupt the adhesion of the participant to the presented virtual scene. It is thus important to measure the accuracy of the auditory spatial cues reproduced by the auditory display and their consistency with the spatial visual cues. This study evaluates auditory localization performances under various unimodal and auditory-visual bimodal conditions in a virtual reality (VR) setup using a stereoscopic display and binaural reproduction over headphones in static conditions. The auditory localization performances observed in the present study are in line with those reported in real conditions, suggesting that VR gives rise to consistent auditory and visual spatial cues. These results validate the use of VR for future psychophysics experiments with auditory and visual stimuli. They also emphasize the importance of a spatially accurate auditory and visual rendering for VR setups.

XSAMPL3D: An Action Description Language for the Animation of Virtual Characters

In this paper we present XSAMPL3D, a novel language for the high-level representation of actions performed on objects by (virtual) humans. XSAMPL3D was designed to serve as action representation language in an imitation-based approach to character animation: First, a human demonstrates a sequence of object manipulations in an immersive Virtual Reality (VR) environment. From this demonstration, an XSAMPL3D description is automatically derived that represents the actions in terms of high-level action types and involved objects. The XSAMPL3D action description can then be used for the synthesis of animations where virtual humans of different body sizes and proportions reproduce the demonstrated action. Actions are encoded in a compact and human-readable XML-format. Thus, XSAMPL3D describtions are also amenable to manual authoring, e.g. for rapid prototyping of animations when no immersive VR environment is at the animator's disposal. However, when XSAMPL3D descriptions are derived from VR interactions, they can accomodate many details of the demonstrated action, such as motion trajectiories,hand shapes and other hand-object relations during grasping. Such detail would be hard to specify with manual motion authoring techniques only. Through the inclusion of language features that allow the representation of all relevant aspects of demonstrated object manipulations, XSAMPL3D is a suitable action representation language for the imitation-based approach to character animation.

OCTAVIS: Optimization Techniques for Multi-GPU Multi-View Rendering

We present a high performance-yet low cost-system for multi-view rendering in virtual reality (VR) applications. In contrast to complex CAVE installations, which are typically driven by one render client per view, we arrange eight displays in an octagon around the viewer to provide a full 360° projection, and we drive these eight displays by a single PC equipped with multiple graphics units (GPUs). In this paper we describe the hardware and software setup, as well as the necessary low-level and high-level optimizations to optimally exploit the parallelism of this multi-GPU multi-view VR system.

Simulating Wind and Warmth in Virtual Reality: Conception, Realization and Evaluation for a CAVE Environment

Wind and warmth sensations proved to be able to enhance users' state of presence in Virtual Reality applications. Still, only few projects deal with their detailed effect on the user and general ways of implementing such stimuli. This work tries to fill this gap: After analyzing requirements for hardware and software concerning wind and warmth simulations, a hardware and also a software setup for the application in a CAVE environment is proposed. The setup is evaluated with regard to technical details and requirements, but also - in the form of a pilot study - in view of user experience and presence. Our setup proved to comply with the requirements and leads to satisfactory results. To our knowledge, the low cost simulation system (approx. 2200 Euro) presented here is one of the most extensive, most flexible and best evaluated systems for creating wind and warmth stimuli in CAVE-based VR applications.

A Comparative Evaluation of Three Skin Color Detection Approaches

Skin segmentation is a challenging task due to several influences such as unknown lighting conditions, skin colored background, and camera limitations. A lot of skin segmentation approaches were proposed in the past including adaptive (in the sense of updating the skin color online) and non-adaptive approaches. In this paper, we compare three skin segmentation approaches that are promising to work well for hand tracking, which is our main motivation for this work. Hand tracking can widely be used in VR/AR e.g. navigation and object manipulation. The first skin segmentation approach is a well-known non-adaptive approach. It is based on a simple, pre-computed skin color distribution. Methods two and three adaptively estimate the skin color in each frame utilizing clustering algorithms. The second approach uses a hierarchical clustering for a simultaneous image and color space segmentation, while the third approach is a pure color space clustering, but with a more sophisticated clustering approach. For evaluation, we compared the segmentation results of the approaches against a ground truth dataset. To obtain the ground truth dataset, we labeled about 500 images captured under various conditions.