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Item Simulation of Facial Muscle Actions Based on Rational Free Form Deformations(Blackwell Science Ltd and the Eurographics Association, 1992) Kalra, Prem; Mangili, Angelo; Thalmann, Nadia Magnenat; Thalmann, DanielThis paper describes interactive facilities for simulating abstract muscle actions using Rational Free Form Deformations (RFFD). The particular muscle action is simulated as the displacement of the control points of the control-unit for an RFFD defined on a region of interest. One or several simulated muscle actions constitute a Minimum Perceptible Action (MPA), which is defined as the atomic action unit, similar to Action Unit (AU) of the Facial Action Coding System (FACS), to build an expression.Item Avatar Markup Language(The Eurographics Association, 2002) Kshirsagar, Sumedha; Magnenat-Thalmann, Nadia; Guye-Vuillème, Anthony; Thalmann, Daniel; Kamyab, Kaveh; Mamdani, Ebrahim; S. Mueller and W. StuerzlingerSynchronization of speech, facial expressions and body gestures is one of the most critical problems in realistic avatar animation in virtual environments. In this paper, we address this problem by proposing a new high-level animation language to describe avatar animation. The Avatar Markup Language (AML), based on XML, encapsulates the Text to Speech, Facial Animation and Body Animation in a unified manner with appropriate synchronization. We use low-level animation parameters, defined by the MPEG-4 standard, to demonstrate the use of the AML. However, the AML itself is independent of any low-level parameters as such. AML can be effectively used by intelligent software agents to control their 3D graphical representations in the virtual environments. With the help of the associated tools, AML also facilitates to create and share 3D avatar animations quickly and easily. We also discuss how the language has been developed and used within the SoNG project framework. The tools developed to use AML in a real-time animation system incorporating intelligent agents and 3D avatars are also discussed subsequently.Item SOME USEFUL BUT RATHER UNUSUAL GRAPHICAL PRIMITIVES(The Eurographics Association, 1981) Magnenat-Thalmann, Nadia; Thalmann, Daniel; Bergeron, Philippe; J. L. EncarnacaoThe MIRALIB library is a powerful graphical library which may be used with MIRA-2D, a graphical PASCAL extension as well as with the standard PASCAL language. MIRALIB includes figure algebra routines, figure measure functions, figure recognition predicates, image transformations as fitting or clearing and animation primitives. The most unusual primitives are presented with the help of a few examples.Item A Flexible Architecture for Virtual Humans in Networked Collaborative Virtual Environments(Blackwell Publishers Ltd and the Eurographics Association, 1997) Sunday Pandzic, Igor; Lee, Elwin; Magnenat Thalmann, Nadia; Capin, Tolga K.; Thalmann, DanielComplex virtual human representation provides more natural interaction and communication among participants in networked virtual environments, hence it is expected to increase the sense of being together within the same virtual world. We present a flexible framework for the integration of virtual humans in networked collaborative virtual environments. A modular architecture allows flexible representation and control of the virtual humans, whether they are controlled by a physical user using all sorts of tracking and other devices, or by an intelligent control program turning them into autonomous actors. The modularity of the system allows for fairly easy extensions and integration with new techniques making it interesting also as a testbed for various domains from "classic" VR to psychological experiments. We present results in terms of functionalities, example applications and measurements of performance and network traffic with an increasing number of participants in the simulation.Item An Informed Environment Dedicated to the Simulation of Virtual Humans in Urban Context(Blackwell Publishers Ltd and the Eurographics Association, 1999) Farenc, Nathalie; Boulic, Ronan; Thalmann, DanielIn this paper, we outline the creation of an Informed Environment, dedicated to urban life simulation.We propose methods and tools for creating and providing the information necessary for animating virtual humans in a city using an Informed Environment. The Informed Environment is based on a hierarchical decomposition of a urban scene into Environment Entities providing geometrical information as well as semantic notions, thus allowing a more realistic simulation of human behaviour. In this manner, virtual humans can integrate with a certain kind of urban knowledge.Item Populating Ancient Pompeii with Crowds of Virtual Romans(The Eurographics Association, 2007) Maim, Jonathan; Haegler, Simon; Yersin, Barbara; Mueller, Pascal; Thalmann, Daniel; Gool, Luc Van; D. Arnold and F. Niccolucci and A. ChalmersPompeii was a Roman city, destroyed and completely buried during an eruption of the volcano Mount Vesuvius. We have revived its past by creating a 3D model of its previous appearance and populated it with crowds of Virtual Romans. In this paper, we detail the process, based on archaeological data, to simulate ancient Pompeii life in real time. In a first step, an annotated city model is generated using procedural modelling. These annotations contain semantic data, such as land usage, building age, and window/door labels. In a second phase, the semantics are automatically interpreted to populate the scene and trigger special behaviors in the crowd, depending on the location of the characters. Finally, we describe the system pipeline, which allows for the simulation of thousands of Virtual Romans in real time.Item Planning Collision-Free Reaching Motions for Interactive Object Manipulation and Grasping(Blackwell Publishers, Inc and the Eurographics Association, 2003) Kallmann, Marcelo; Aubel, Amaury; Abaci, Tolga; Thalmann, DanielWe present new techniques that use motion planning algorithms based on probabilistic roadmaps to control 22 degrees of freedom (DOFs) of human-like characters in interactive applications. Our main purpose is the automatic synthesis of collision-free reaching motions for both arms, with automatic column control and leg flexion. Generated motions are collision-free, in equilibrium, and respect articulation range limits. In order to deal with the high (22) dimension of our configuration space, we bias the random distribution of configurations to favor postures most useful for reaching and grasping. In addition, extensions are presented in order to interactively generate object manipulation sequences: a probabilistic inverse kinematics solver for proposing goal postures matching pre-designed grasps; dynamic update of roadmaps when obstacles change position; online planning of object location transfer; and an automatic stepping control to enlarge the character's reachable space. This is, to our knowledge, the first time probabilistic planning techniques are used to automatically generate collision-free reaching motions involving the entire body of a human-like character at interactive frame rates.Categories and Subject Descriptors (according to ACM CCS): I.3.7 [Computer Graphics]: Three-Dimensional Graphics and RealismItem Real-time Shader Rendering for Crowds in Virtual Heritage(The Eurographics Association, 2005) Ciechomski, Pablo de Heras; Schertenleib, Sébastien; Maïm, Jonathan; Maupu, Damien; Thalmann, Daniel; Mark Mudge and Nick Ryan and Roberto ScopignoWe present a method of fully dynamically rendered virtual humans with variety in color, animation and appearance. This is achieved by using vertex and fragment shaders programmed in the OpenGL shading language (GLSL). We then compare our results with a fixed function pipeline based approach. We also show a color variety creation GUI using HSB color space restriction. An improved version of the LOD pipeline for our virtual characters is presented. With these new techniques, we are able to use a full dynamic animation range in the crowd populating the Aphrodisias odeon (which is part of the ERATO project), i.e., a greater repertoire of animations, smooth transitions and more variety and speed. We show how a multi-view of the rendering data can ensure good batching of rendering primitives and comfortable constant time access.Item An Efficient and Flexible Perception Pipeline for Autonomous Agents(Blackwell Publishers Ltd and the Eurographics Association, 1999) Bordeux, Christophe; Boulic, Ronan; Thalmann, DanielAgents in virtual environments require a combination of perception and action to behave in an autonomous way. We extend a software architecture for the management of actions blending, called AGENTlib, with a perception mechanism. The perception system provides a uniform interface to various techniques in the field of virtual perception, including synthetic vision, database access and perception persistency. We describe the framework we designed to efficiently filter valuable information from the scene and we address concerns about computation redundancy and data propagation through multiple filtering modules.Item A Hand Control and Automatic Grasping System for Synthetic Actors(Blackwell Science Ltd and the Eurographics Association, 1994) Sanso, Ramon Mas; Thalmann, DanielIn the computer animation field, the interest for grasping has appeared with the development of synthetic actors. Based on a grasp taxonomy, we propose a completely automatic grasping system for synthetic actors. In particular, the system can decide to use a pinch when the object is too small to be grasped by more than two fingers or to use a two-handed grasp when the object is too large. The system also offers both direct and inverse kinematics to control the articulations. In order to ensure realistic looking closing of the hand, several of the joints are constrained. A brief description of the system and results are also presented.