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Item Editing Object Behaviour in Video Sequences(The Eurographics Association and Blackwell Publishing Ltd, 2009) Scholz, Volker; El-Abed, Sascha; Seidel, Hans-Peter; Magnor, MarcusWhile there are various commercial-strength editing tools available today for still images, object-based manipulation of real-world video footage is still a challenging problem. In this system paper, we present a framework for interactive video editing. Our focus is on footage from a single, conventional video camera. By relying on spatio-temporal editing techniques operating on the video cube, we do not need to recover 3D scene geometry. Our framework is capable of removing and inserting objects, object motion editing, non-rigid object deformations, keyframe interpolation, as well as emulating camera motion. We demonstrate how movie shots with moderate complexity can be persuasively modified during post-processing.Item Biorthogonal Wavelets Based on Interpolatory Subdivision(The Eurographics Association and Blackwell Publishing Ltd, 2009) Wang, H.; Ma, W.This article presents an efficient construction of biorthogonal wavelets built upon an interpolatory subdivision for quadrilateral meshes. The interpolatory subdivision scheme is first turned into a scheme for reversible primitive wavelet synthesis. Some desired properties are then incorporated in the primitive wavelet using the lifting scheme. The analysis and synthesis algorithms of the resulting new wavelet are finally obtained as local and in-place lifting operations. The wavelet inherits the advantage of refinement with added levels of resolution. Numerical experiments show that the lifted wavelet built upon interpolatory, subdivision has sufficient stability and better performance in dealing with closed or open semi-regular quadrilateral meshes compared with other existing wavelets for quadrilateral manifold meshes.Item 2009 Eurographics Symposium on Parallel Graphics and Visualization(The Eurographics Association and Blackwell Publishing Ltd, 2009) Comba, Joao; Daniel, Weiskopf; Debattista, KurtItem State of the Art in Ray Tracing Animated Scenes(The Eurographics Association and Blackwell Publishing Ltd, 2009) Wald, Ingo; Mark, William R.; Guenther, Johannes; Boulos, Solomon; Ize, Thiago; Hunt, Warren; Parker, Steven G.; Shirley, PeterRay tracing has long been a method of choice for off-line rendering, but traditionally was too slow for interactive use. With faster hardware and algorithmic improvements this has recently changed, and real-time ray tracing is finally within reach. However, real-time capability also opens up new problems that do not exist in an off-line environment. In particular real-time ray tracing offers the opportunity to interactively ray trace moving/animated scene content.This presents a challenge to the data structures that have been developed for ray tracing over the past few decades. Spatial data structures crucial for fast ray tracing must be rebuilt or updated as the scene changes, and this can become a bottleneck for the speed of ray tracing. This bottleneck has recently received much attention by researchers and that has resulted in a multitude of different algorithms, data structures and strategies for handling animated scenes. The effectiveness of techniques for ray tracing dynamic scenes vary dramatically depending on details such as scene complexity, model structure, type of motion and the coherency of the rays. Consequently, there is so far no approach that is best in all cases, and determining the best technique for a particular problem can be a challenge. In this State of the Art Report (STAR), we aim to survey the different approaches to ray tracing animated scenes, discussing their strengths and weaknesses, and their relationship to other approaches. The overall goal is to help the reader choose the best approach depending on the situation, and to expose promising areas where there is potential for algorithmic improvements.Item Item New EUROGRAPHICS Fellows(The Eurographics Association and Blackwell Publishing Ltd, 2009)Item A Time Model for Time-Varying Visualization(The Eurographics Association and Blackwell Publishing Ltd, 2009) Wolter, M.; Assenmacher, I.; Hentschel, B.; Schirski, M.; Kuhlen, T.The analysis of unsteady phenomena is an important topic for scientific visualization. Several time-dependent visualization techniques exist, as well as solutions for dealing with the enormous size of time-varying data in interactive visualization. Many current visualization toolkits support displaying time-varying data sets. However, for the interactive exploration of time-varying data in scientific visualization, no common time model that describes the temporal properties which occur in the visualization process has been established. In this work, we propose a general time model which classifies the time frames of simulation phenomena and the connections between different time scales in the analysis process. This model is designed for intuitive interaction with time in visualization applications for the domain expert as well as for the developer of visualization tools. We demonstrate the benefits of our model by applying it to two use cases with different temporal properties.Item Visualization of Multi-Variate Scientific Data(The Eurographics Association and Blackwell Publishing Ltd, 2009) Fuchs, R.; Hauser, H.In this state-of-the-art report we discuss relevant research works related to the visualization of complex, multi-variate data. We discuss how different techniques take effect at specific stages of the visualization pipeline and how they apply to multi-variate data sets being composed of scalars, vectors and tensors. We also provide a categorization of these techniques with the aim for a better overview of related approaches. Based on this classification we highlight combinable and hybrid approaches and focus on techniques that potentially lead towards new directions in visualization research. In the second part of this paper we take a look at recent techniques that are useful for the visualization of complex data sets either because they are general purpose or because they can be adapted to specific problems.Item Specular Effects on the GPU: State of the Art(The Eurographics Association and Blackwell Publishing Ltd, 2009) Szirmay-Kalos, Laszlo; Umenhoffer, Tamas; Patow, Gustavo; Szecsi, Laszlo; Sbert, MateuThis survey reviews algorithms that can render specular, i.e. mirror reflections, refractions, and caustics on the GPU. We establish a taxonomy of methods based on the three main different ways of representing the scene and computing ray intersections with the aid of the GPU, including ray tracing in the original geometry, ray tracing in the sampled geometry, and geometry transformation. Having discussed the possibilities of implementing ray tracing, we consider the generation of single reflections/refractions, interobject multiple reflections/refractions, and the general case which also includes self-reflections or refractions. Moving the focus from the eye to the light sources, caustic effect generation approaches are also examined.Item Education Programme at Eurographics 2009(The Eurographics Association and Blackwell Publishing Ltd, 2009) Domik, G.; Scateni, R.