Jean-Marc Hasenfratz

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Recent advances in GPU technology have produced a shift in focus for real-time rendering applications, whereby improvements in image quality are sought in addition to raw polygon display performance. Rendering effects such as antialiasing, motion blur and shadow casting are becoming commonplace and will likely be considered indispensable in the near future.(More)
Real-time video acquisition is becoming a reality with the most recent camera technology. Three-dimensional models can be reconstructed from multiple views using visual hull carving techniques. However the combination of these approaches to obtain a moving 3D model from simultaneous video captures remains a technological challenge. In this paper we(More)
Shadows, particularly soft shadows, play an important role in the visual perception of a scene by providing visual cues about the shape and position of objects. Several recent algorithms produce soft shadows at interactive rates, but they do not scale well with the number of polygons in the scene or only compute the outer penumbra. In this paper, we present(More)
In this paper, we show how to capture an actor with no intrusive trackers and without any special environment like blue set, how to estimate its 3D-geometry and how to insert this geometry into a virtual world in real-time. We use several cameras in conjunction with background subtraction to produce silhouettes of the actor as observed from the different(More)
The calculation of radiant energy balance in complex scenes has been made possible by hierarchical radiosity methods based on clustering mechanisms. Although clustering offers an elegant theoretical solution by reducing the asymptotic complexity of the algorithm, its practical use raises many difficulties, and may result in image artifacts or unexpected(More)
We introduce a simple, yet efficient extension to the hierarchical radiosity algorithm for the simulation of global illumination, taking advantage of a distributed shared memory (DSM) parallel architecture. Our task definition is based on a very fine grain decomposition of the refinement process at the level of individual pairs of hierarchical elements,(More)
In the context of Augmented Reality applications, the goal of the Cyber-II project is to simulate, in real-time, the presence of a person (e.g. a TV presenter or a teacher) in a virtual environment. This simulation consists mainly in visualizing the combined scenario, and providing tools for interaction between the real person, the virtual environment, and(More)