Why Death Matters: Understanding Gameworld Experience

This article presents a study of the staging and implementation of death and the death penalty in a number of popular MMOGs and relates it to players general experience of gameworlds. Game mechanics, writings and stories by designers and players, and the results of an online survey are analysed and discussed. The study shows that the death penalty is implemented much in the same way across worlds; that death can be both trivial and non-trivial, part of the grind of everyday life, or essential in the creation of heroes, depending on context. In whatever function death may serves, it is argued that death plays an important part in the shaping and emergence of the social culture of a world, and in the individual players experience of life within it.

Video Search: New Challenges in the Pervasive Digital Video Era

The explosion of multimedia digital content and the development of technologies that go beyond traditional broadcast and TV have rendered access to such content important for all end-users of these technologies. While originally developed for providing access to multimedia digital libraries, video search technologies assume now a more demanding role. In this paper, we attempt to shed light onto this new role of video search technologies, looking at the rapid developments in the related market, the lessons learned from state of art video search prototypes developed mainly in the digital libraries context and the new technological challenges that have risen. We focus on one of the latter, i.e., the development of cross-media decision mechanisms, drawing examples from REVEAL THIS, an FP6 project on the retrieval of video and language for the home user. We argue, that efficient video search holds a key to the usability of the new ”pervasive digital video” technologies and that it should involve cross-media decision mechanisms.

Video Composer and Live Video Conductor: Future Professions for the Interactive Digital Broadcasting Industry

Innovations in hardware and network technologies lead to an exploding number of non-interrelated parallel media streams. Per se this does not mean any additional value for consumers. Broadcasting and advertisement industries have not yet found new formats to reach the individual user with their content. In this work we propose and describe a novel digital broadcasting framework, which allows for the live staging of (mass) media events and improved consumer personalisation. In addition new professions for future TV production workflows which will emerge are described, namely the 'video composer' and the 'live video conductor'.

Semi-Automated Creation of Converged iTV Services: From Macromedia Director Simulations to Services Ready for Broadcast

While sound and video may capture viewers' attention, interaction can captivate them. This has not been available prior to the advent of Digital Television. In fact, what lies at the heart of the Digital Television revolution is this new type of interactive content, offered in the form of interactive Television (iTV) services. On top of that, the new world of converged networks has created a demand for a new type of converged services on a range of mobile terminals (Tablet PCs, PDAs and mobile phones). This paper aims at presenting a new approach to service creation that allows for the semi-automatic translation of simulations and rapid prototypes created in the accessible desktop multimedia authoring package Macromedia Director into services ready for broadcast. This is achieved by a series of tools that de-skill and speed-up the process of creating digital TV user interfaces (UI) and applications for mobile terminals. The benefits of rapid prototyping are essential for the production of these new types of services, and are therefore discussed in the first section of this paper. In the following sections, an overview of the operation of content, service, creation and management sub-systems is presented, which illustrates why these tools compose an important and integral part of a system responsible of creating, delivering and managing converged broadcast and telecommunications services. The next section examines a number of metadata languages candidates for describing the iTV services user interface and the schema language adopted in this project. A detailed description of the operation of the two tools is provided to offer an insight of how they can be used to de-skill and speed-up the process of creating digital TV user interfaces and applications for mobile terminals. Finally, representative broadcast oriented and telecommunication oriented converged service components are also introduced, demonstrating how these tools have been used to generate different types of services.

Methods and Applications in Interactive Broadcasting

Interactive TV technology has been addressed in many previous works, but there is sparse research on the topic of interactive content broadcasting and how to support the production process. In this article, the interactive broadcasting process is broadly defined to include studio technology and digital TV applications at consumer set-top boxes. In particular, augmented reality studio technology employs smart-projectors as light sources and blends real scenes with interactive computer graphics that are controlled at end-user terminals. Moreover, TV producer-friendly multimedia authoring tools empower the development of novel TV formats. Finally, the support for user-contributed content raises the potential to revolutionize the hierarchical TV production process, by introducing the viewer as part of content delivery chain.

Topologically Accurate Dual Isosurfacing Using Ray Intersection

“Dual contouring” approaches provide an alternative to standard Marching Cubes (MC) method to extract and approximate an isosurface from trivariate data given on a volumetric mesh. These dual approaches solve some of the problems encountered by the MC methods. We present a simple method based on the MC method and the ray intersection technique to compute isosurface points in the cell interior. One of the advantages of our method is that it does not require us to use Hermite interpolation scheme, unlike other dual contouring methods. We perform a complete analysis of all possible configurations to generate a look-up table for all configurations. We use the look-up table to optimize the ray-intersection method to obtain minimum number of points necessarily sufficient for defining topologically correct isosurfaces in all possible configurations. Isosurface points are connected using a simple strategy.

Passive-Active Geometric Calibration for View-Dependent Projections onto Arbitrary Surfaces

In this paper we present a hybrid technique for correcting distortions that appear when projecting images onto geometrically complex, colored and textured surfaces. It analyzes the optical flow that results from perspective distortions during motions of the observer and tries to use this information for computing the correct image warping. If this fails due to an unreliable optical flow, an accurate -but slower and visiblestructured light projection is automatically triggered. Together with an appropriate radiometric compensation, view-dependent content can be projected onto arbitrary everyday surfaces. An implementation mainly on the GPU ensures fast frame rates.

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.

Precise Near-to-Head Acoustics with Binaural Synthesis

For enhanced immersion into a virtual scene more than just the visual sense should be addressed by a Virtual Reality system. Additional auditory stimulation appears to have much potential, as it realizes a multisensory system. This is especially useful when the user does not have to wear any additional hardware, e.g., headphones. Creating a virtual sound scene with spatially distributed sources requires a technique for adding spatial cues to audio signals and an appropriate reproduction. In this paper we present a real-time audio rendering system that combines dynamic crosstalk cancellation and multi-track binaural synthesis for virtual acoustical imaging. This provides the possibility of simulating spatially distributed sources and, in addition to that, near-to-head sources for a freely moving listener in room-mounted virtual environments without using any headphones. A special focus will be put on near-to-head acoustics, and requirements in respect of the head-related transfer function databases are discussed.

Playing with the Real World

In this paper we provide a framework that enables the rapid development of applications using non-standard input devices. Flash is chosen as programming language since it can be used for quickly assembling applications. We overcome the difficulties of Flash to access external devices by introducing a very generic concept: The state information generated by input devices is transferred to a PC where a program collects them, interprets them and makes them available on a web server. Application developers can now integrate a Flash component that accesses the data stored in XML format and directly use it in their application.

Mitarbeiterqualifizierung in der virtuellen Realität - Implementierung und Evaluation einer didaktischen Simulationsanwendung

Virtuelle Teamtrainingsanwendungen sind im militärischen Bereich seit über 20 Jahren mit großem Erfolg im Einsatz. Bei geeigneten Randbedingungen schafft dieses Qualifizierungsmedium neben einer erheblichen Reduzierung von Ausbildungsdauer und -kosten beachtliche Vorteile hinsichtlich der einhergehenden Ausbildungsqualität. Im Rahmen des Bayerischen Forschungsverbundes ForLog wird in Kooperation des Lehrstuhls für Fördertechnik Materialfluss Logistik (fml) und der Ray Sono AG das Potenzial entsprechender Qualifizierungsansätze im zivilen Industriesektor praxisnah untersucht.

An Architecture for End-User TV Content Enrichment

This paper proposes an extension to the televisionwatching paradigm that permits an end-user to enrich broadcast content. Examples of this enriched content are: virtual edits that allow the order of presentation within the content to be changed or that allow the content to be subsetted; conditional text, graphic or video objects that can be placed to appear within content and triggered by viewer interaction; additional navigation links that can be added to structure how other users view the base content object. The enriched content can be viewed directly within the context of the TV viewing experience. It may also be shared with other users within a distributed peer group. Our architecture is based on a model that allows the original content to remain unaltered, and which respects DRM restrictions on content reuse. The fundamental approach we use is to define an intermediate content enhancement layer that is based on the W3C’s SMIL language. Using a pen-based enhancement interface, end-users can manipulate content that is saved in a home PDR setting. This paper describes our architecture and it provides several examples of how our system handles content enhancement. We also describe a reference implementation for creating and viewing enhancements.

Content Classification of Multimedia Documents using Partitions of Low-Level Features

Audio-visual documents obtained from German TV news are classified according to the IPTC topic categorization scheme. To this end usual text classification techniques are adapted to speech, video, and non-speech audio. For each of the three modalities word analogues are generated: sequences of syllables for speech, “video words” based on low level color features (color moments, color correlogram and color wavelet), and “audio words” based on low-level spectral features (spectral envelope and spectral flatness) for non-speech audio. Such audio and video words provide a means to represent the different modalities in a uniform way. The frequencies of the word analogues represent audio-visual documents: the standard bag-of-words approach. Support vector machines are used for supervised classification in a 1 vs. n setting. Classification based on speech outperforms all other single modalities. Combining speech with non-speech audio improves classification. Classification is further improved by supplementing speech and non-speech audio with video words. Optimal F-scores range between 62% and 94% corresponding to 50% - 84% above chance. The optimal combination of modalities depends on the category to be recognized. The construction of audio and video words from low-level features provide a good basis for the integration of speech, non-speech audio and video.

View-Dependent Extraction of Contours with Distance Transforms for Adaptive Polygonal for adaptive polygonal Mesh-Simplification

During decades Distance Transforms have proven to be useful for many image processing applications, and more recently, they have started to be used in computer graphics environments. The goal of this paper is to propose a new technique based on Distance Transforms for detecting mesh elements which are close to the objects' external contour (from a given point of view), and using this information for weighting the approximation error which will be tolerated during the mesh simplification process. The obtained results are evaluated in two ways: visually and using an objective metric that measures the geometrical difference between two polygonal meshes.

The art to keep in touch: The ''good use'' of Lagrange multipliers

Physically-based modeling for computer animation allows to produce more realistic motions in less time without requiring the expertise of skilled animators. But, a computer animation is not only a numerical simulation based on classical mechanics since it follows a precise story-line. One common way to define aims in an animation is to add geometric constraints. There are several methods to manage these constraints within a physically-based framework. In this paper, we present an algorithm for constraints handling based on Lagrange multipliers. After few remarks on the equations of motion that we use, we present a first algorithm proposed by Platt. We show with a simple example that this method is not reliable. Our contribution consists in improving this algorithm to provide an efficient and robust method to handle simultaneous active constraints.