The Experts below are selected from a list of 25161 Experts worldwide ranked by ideXlab platform
Georgios N. Yannakakis - One of the best experts on this subject based on the ideXlab platform.
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Adapting Virtual Camera behaviour through player modelling
User Modeling and User-Adapted Interaction, 2015Co-Authors: Paolo Burelli, Georgios N. YannakakisAbstract:Research in Virtual Camera control has focused primarily on finding methods to allow designers to place Cameras effectively and efficiently in dynamic and unpredictable environments, and to generate complex and dynamic plans for cinematography in Virtual environments. In this article, we propose a novel approach to Virtual Camera control, which builds upon Camera control and player modelling to provide the user with an adaptive point-of-view. To achieve this goal, we propose a methodology to model the player’s preferences on Virtual Camera movements and we employ the resulting models to tailor the viewpoint movements to the player type and her game-play style. Ultimately, the methodology is applied to a 3D platform game and is evaluated through a controlled experiment; the results suggest that the resulting adaptive cinematographic experience is favoured by some player types and it can generate a positive impact on the game performance.
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EvoApplications - A Benchmark for Virtual Camera Control
Applications of Evolutionary Computation, 2015Co-Authors: Paolo Burelli, Georgios N. YannakakisAbstract:Automatically animating and placing the Virtual Camera in a dynamic environment is a challenging task. The Camera is expected to maximise and maintain a set of properties — i.e. visual composition — while smoothly moving through the environment and avoiding obstacles. A large number of different solutions to the problem have been proposed so far including, for instance, evolutionary techniques, swarm intelligence or ad hoc solutions. However, the large diversity of the solutions and the lack of a common benchmark, made any comparative analysis of the different solutions extremely difficult. For this reason, in this paper, we propose a benchmark for the problem of Virtual Camera control and we analyse a number of different problems in different Virtual environments. Each of these scenarios is described through a set of complexity measures and, as a result of this analysis, a subset of scenarios is selected as the core of the benchmark.
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EvoApplications - Diversified Virtual Camera composition
Applications of Evolutionary Computation, 2012Co-Authors: Mike Preuss, Paolo Burelli, Georgios N. YannakakisAbstract:The expressive use of Virtual Cameras and the automatic generation of cinematics within 3D environments shows potential to extend the communicative power of films into games and Virtual worlds. In this paper we present a novel solution to the problem of Virtual Camera composition based on niching and restart evolutionary algorithms that addresses the problem of diversity in shot generation by simultaneously identifying multiple valid Camera Camera configurations. We asses the performance of the proposed solution against a set of state-of-the-art algorithms in Virtual Camera optimisation.
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FDG - Modelling Virtual Camera behaviour through player gaze
Proceedings of the 6th International Conference on Foundations of Digital Games - FDG '11, 2011Co-Authors: Andrea Picardi, Paolo Burelli, Georgios N. YannakakisAbstract:In a three-dimensional Virtual environment, aspects such as narrative and interaction largely depend on the placement and animation of the Virtual Camera. Therefore, Virtual Camera control plays a critical role in player experience and, thereby, in the overall quality of a computer game. Both game industry and game AI research focus on the development of increasingly sophisticated systems to automate the control of the Virtual Camera integrating artificial intelligence algorithms within physical simulations. However, in both industry and academia little research has been carried out on the relationship between Virtual Camera, game-play and player behaviour. We run a game user experiment to shed some light on this relationship and identify relevant differences between Camera behaviours through different game sessions, playing behaviours and player gaze patterns. Results show that users can be efficiently profiled in dissimilar clusters according to Camera control as part of their gameplay behaviour.
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Smart Graphics - Towards adaptive Virtual Camera control in computer games
Smart Graphics, 2011Co-Authors: Paolo Burelli, Georgios N. YannakakisAbstract:Automatic Camera control aims to define a framework to control Virtual Camera movements in dynamic and unpredictable Virtual environments while ensuring a set of desired visual properties. We investigate the relationship between Camera placement and playing behaviour in games and build a user model of the Camera behaviour that can be used to control Camera movements based on player preferences. For this purpose, we collect eye gaze, Camera and game-play data from subjects playing a 3D platform game, we cluster gaze and Camera information to identify Camera behaviour profiles and we employ machine learning to build predictive models of the Virtual Camera behaviour. The performance of the models on unseen data reveals accuracies above 70% for all the player behaviour types identified. The characteristics of the generated models, their limits and their use for creating adaptive automatic Camera control in games is discussed.
Paolo Burelli - One of the best experts on this subject based on the ideXlab platform.
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Adapting Virtual Camera behaviour through player modelling
User Modeling and User-Adapted Interaction, 2015Co-Authors: Paolo Burelli, Georgios N. YannakakisAbstract:Research in Virtual Camera control has focused primarily on finding methods to allow designers to place Cameras effectively and efficiently in dynamic and unpredictable environments, and to generate complex and dynamic plans for cinematography in Virtual environments. In this article, we propose a novel approach to Virtual Camera control, which builds upon Camera control and player modelling to provide the user with an adaptive point-of-view. To achieve this goal, we propose a methodology to model the player’s preferences on Virtual Camera movements and we employ the resulting models to tailor the viewpoint movements to the player type and her game-play style. Ultimately, the methodology is applied to a 3D platform game and is evaluated through a controlled experiment; the results suggest that the resulting adaptive cinematographic experience is favoured by some player types and it can generate a positive impact on the game performance.
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EvoApplications - A Benchmark for Virtual Camera Control
Applications of Evolutionary Computation, 2015Co-Authors: Paolo Burelli, Georgios N. YannakakisAbstract:Automatically animating and placing the Virtual Camera in a dynamic environment is a challenging task. The Camera is expected to maximise and maintain a set of properties — i.e. visual composition — while smoothly moving through the environment and avoiding obstacles. A large number of different solutions to the problem have been proposed so far including, for instance, evolutionary techniques, swarm intelligence or ad hoc solutions. However, the large diversity of the solutions and the lack of a common benchmark, made any comparative analysis of the different solutions extremely difficult. For this reason, in this paper, we propose a benchmark for the problem of Virtual Camera control and we analyse a number of different problems in different Virtual environments. Each of these scenarios is described through a set of complexity measures and, as a result of this analysis, a subset of scenarios is selected as the core of the benchmark.
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Adapting Virtual Camera Behaviour
2013Co-Authors: Paolo BurelliAbstract:In a three-dimensional Virtual environment aspects such as narrative and interaction completely depend on the Camera since the Camera defines the player’s point of view. Most research works in automatic Camera control aim to take the control of this aspect from the player to automatically generate cinematographic game experiences reducing, however, the player’s feeling of agency. We propose a methodology to integrate the player in the Camera control loop that allows to design and generate personalised cinematographic experiences. Furthermore, we present an evaluation of the aforementioned methodology showing that the generated Camera movements are positively perceived by novice asnd intermediate players.
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EvoApplications - Diversified Virtual Camera composition
Applications of Evolutionary Computation, 2012Co-Authors: Mike Preuss, Paolo Burelli, Georgios N. YannakakisAbstract:The expressive use of Virtual Cameras and the automatic generation of cinematics within 3D environments shows potential to extend the communicative power of films into games and Virtual worlds. In this paper we present a novel solution to the problem of Virtual Camera composition based on niching and restart evolutionary algorithms that addresses the problem of diversity in shot generation by simultaneously identifying multiple valid Camera Camera configurations. We asses the performance of the proposed solution against a set of state-of-the-art algorithms in Virtual Camera optimisation.
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FDG - Modelling Virtual Camera behaviour through player gaze
Proceedings of the 6th International Conference on Foundations of Digital Games - FDG '11, 2011Co-Authors: Andrea Picardi, Paolo Burelli, Georgios N. YannakakisAbstract:In a three-dimensional Virtual environment, aspects such as narrative and interaction largely depend on the placement and animation of the Virtual Camera. Therefore, Virtual Camera control plays a critical role in player experience and, thereby, in the overall quality of a computer game. Both game industry and game AI research focus on the development of increasingly sophisticated systems to automate the control of the Virtual Camera integrating artificial intelligence algorithms within physical simulations. However, in both industry and academia little research has been carried out on the relationship between Virtual Camera, game-play and player behaviour. We run a game user experiment to shed some light on this relationship and identify relevant differences between Camera behaviours through different game sessions, playing behaviours and player gaze patterns. Results show that users can be efficiently profiled in dissimilar clusters according to Camera control as part of their gameplay behaviour.
Marc Christie - One of the best experts on this subject based on the ideXlab platform.
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Efficient Composition for Virtual Camera Control
2012Co-Authors: Christophe Lino, Marc ChristieAbstract:Automatically positioning a Virtual Camera in a 3D environment given the specification of visual properties to be satisfied (on-screen layout of subjects, vantage angles, visibility) is a complex and challenging problem. Most approaches tackle the problem by expressing visual properties as constraints or functions to optimize, and rely on computationally expensive search techniques to explore the solution space. We show here how to express and solve the exact on-screen positioning of two or three subjects using a simple and very efficient technique. We express the solution space for each couple of subjects as a 2D manifold surface. We demonstrate how to use this manifold surface to solve Blinn's spacecraft problem with a straightforward algebraic approach. We extend the solution to three subjects and we show how to cast the complex 6D optimization problem tackled by most contributions in the field in a simple 2D optimization on the manifold surface by pruning large portions of the search space. The result is a robust and very efficient technique which finds a wide range of applications in Virtual Camera control and more generally in computer graphics.
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Symposium on Computer Animation - Efficient composition for Virtual Camera control
2012Co-Authors: Christophe Lino, Marc ChristieAbstract:Automatically positioning a Virtual Camera in a 3D environment given the specification of visual properties to be satisfied (on-screen layout of subjects, vantage angles, visibility) is a complex and challenging problem. Most approaches tackle the problem by expressing visual properties as constraints or functions to optimize, and rely on computationally expensive search techniques to explore the solution space. We show here how to express and solve the exact on-screen positioning of two or three subjects using a simple and very efficient technique. We express the solution space for each couple of subjects as a 2D manifold surface. We demonstrate how to use this manifold surface to solve Blinn's spacecraft problem with a straightforward algebraic approach. We extend the solution to three subjects and we show how to cast the complex 6D optimization problem tackled by most contributions in the field in a simple 2D optimization on the manifold surface by pruning large portions of the search space. The result is a robust and very efficient technique which finds a wide range of applications in Virtual Camera control and more generally in computer graphics.
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Smart Graphics - A Spatio-temporal Reasoning System for Virtual Camera Planning
Smart Graphics, 2009Co-Authors: Marc Christie, Fabrice Lamarche, Frédéric BenhamouAbstract:The problem of Virtual Camera planning consists in computing Camera paths in Virtual environments that satisfy given cinematographic properties. In this article, we present a spatio-temporal query system for reasoning over the cinematographic expressiveness of a dynamic 3D scene. We offer a declarative language with quantifiers based on a first order logic representation. Prior to any query, we fully characterize each spatial and temporal region of the search-space according to a broad set of properties. We rely on interval-based constraint techniques to guarantee the completeness of the characterization. Then in order to answer a query, we build a digraph that connects over space and time the areas satisfying the request. The exploration of this digraph together with its connectivity properties provide the user with the identification of distinct classes of solutions as well as the full set of Camera paths with their temporal validity. Applications are found in film prototyping, e.g. when a director needs to explore the staging, shot and editing possibilities in real world, by using Virtual environments, or in automated and semi-automated editing.
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a semantic space partitioning approach to Virtual Camera composition
Computer Graphics Forum, 2005Co-Authors: Marc Christie, Jean-marie NormandAbstract:In this paper, we present a semantic space partitioning (SSP) approach to the Virtual Camera composition problem. Virtual Camera composition (VCC) consists in positioning a Camera in a Virtual world, such that the resulting image satises a set of visual cinematographic properties. Whereas most related works concentrate on numerically computing a unique Camera position satisfying the problem, we offer to isolate identical possible solutions in 3D volumes with respect to their visual properties, and to propose them to the user. We introduce the notion of semantic volumes as an extension of visual aspects to characterize, compute and manipulate distinct solution sets. Our approach relies on (1) a space partitioning process derived from a study of possible Camera locations w.r.t. to the objects in the scene and (2) local search numerical techniques to compute good representatives of each volume. This work is motivated by the lack of VCC tools in 3D software and the will to integrate cinematographic semantics in the description, solving and interaction processes. Experimental results illustrate the suitability of our approach for identifying and providing distinct solution sets. Furthermore, the exploitation of the semantic volumes lays the groundwork for natural and efcient user interaction by providing knowledge and reasoning on possible classes of solutions.
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Virtual Camera planning : A survey
Lecture Notes in Computer Science, 2005Co-Authors: Marc Christie, Jean-marie Normand, Rumesh Machap, Patrick Olivier, Jonathan H. PickeringAbstract:Modelling, animation and rendering has dominated research computer graphics yielding increasingly rich and realistic Virtual worlds. The complexity, richness and quality of the Virtual worlds are viewed through a single media that is a Virtual Camera. In order to properly convey information, whether related to the characters in a scene, the aesthetics of the composition or the emotional impact of the lighting, particular attention must be given to how the Camera is positioned and moved. This paper presents an overview of automated Camera planning techniques. After analyzing the requirements with respect to shot properties, we review the solution techniques and present a broad classification of existing approaches. We identify the principal shortcomings of existing techniques and propose a set of objectives for research into automated Camera planning.
Jonathan H. Pickering - One of the best experts on this subject based on the ideXlab platform.
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Virtual Camera planning : A survey
Lecture Notes in Computer Science, 2005Co-Authors: Marc Christie, Jean-marie Normand, Rumesh Machap, Patrick Olivier, Jonathan H. PickeringAbstract:Modelling, animation and rendering has dominated research computer graphics yielding increasingly rich and realistic Virtual worlds. The complexity, richness and quality of the Virtual worlds are viewed through a single media that is a Virtual Camera. In order to properly convey information, whether related to the characters in a scene, the aesthetics of the composition or the emotional impact of the lighting, particular attention must be given to how the Camera is positioned and moved. This paper presents an overview of automated Camera planning techniques. After analyzing the requirements with respect to shot properties, we review the solution techniques and present a broad classification of existing approaches. We identify the principal shortcomings of existing techniques and propose a set of objectives for research into automated Camera planning.
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Smart Graphics - Virtual Camera planning: a survey
Smart Graphics, 2005Co-Authors: Marc Christie, Jean-marie Normand, Rumesh Machap, Patrick Olivier, Jonathan H. PickeringAbstract:Modelling, animation and rendering has dominated research computer graphics yielding increasingly rich and realistic Virtual worlds. The complexity, richness and quality of the Virtual worlds are viewed through a single media that is a Virtual Camera. In order to properly convey information, whether related to the characters in a scene, the aesthetics of the composition or the emotional impact of the lighting, particular attention must be given to how the Camera is positioned and moved. This paper presents an overview of automated Camera planning techniques. After analyzing the requirements with respect to shot properties, we review the solution techniques and present a broad classification of existing approaches. We identify the principal shortcomings of existing techniques and propose a set of objectives for research into automated Camera planning.
B S Manjunath - One of the best experts on this subject based on the ideXlab platform.
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Region of interest extraction and Virtual Camera control based on panoramic video capturing
IEEE Transactions on Multimedia, 2005Co-Authors: Xinding Sun, Jonathan Foote, Don Kimber, B S ManjunathAbstract:We present a system for automatically extracting the region of interest (ROI) and controlling Virtual Cameras' control based on panoramic video. It targets applications such as classroom lectures and video conferencing. For capturing panoramic video, we use the FlyCam system that produces high resolution, wide-angle video by stitching video images from multiple stationary Cameras. To generate conventional video, a region of interest can be cropped from the panoramic video. We propose methods for ROI detection, tracking, and Virtual Camera control that work in both the uncompressed and compressed domains. The ROI is located from motion and color information in the uncompressed domain and macroblock information in the compressed domain, and tracked using a Kalman filter. This results in Virtual Camera control that simulates human controlled video recording. The system has no physical Camera motion and the Virtual Camera parameters are readily available for video indexing.
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panoramic video capturing and compressed domain Virtual Camera control
ACM Multimedia, 2001Co-Authors: Xinding Sun, Jonathan Foote, Don Kimber, B S ManjunathAbstract:A system for capturing panoramic video and a novel method for corresponding compressed domain Virtual Camera control is presented. It targets applications such as classroom lectures and video conferencing. The proposed method is based on the FlyCam panoramic video system that is designed to produce high resolution and wide-angle video sequences by stitching the video pictures from multiple stationary Cameras. The panoramic video sequence is compressed into an MPEG-2 stream for delivery. The proposed method integrates region of Interest (ROI) detection, tracking, and Virtual Camera control, and works on compressed domain information only. It first detects the ROI in the P (predictive coded) picture using only the macroblock type information, It then up-samples this detection result to obtain the ROI of the whole video stream. The ROI is tracked using a Kalman filter. The Kalman filter estimation results are used for Virtual Camera control that simulates human controlled video recording. The system has no physical Camera motion and the Virtual Camera parameters are readily available for video indexing. The proposed system has been implemented for real time processing.
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ACM Multimedia - Panoramic video capturing and compressed domain Virtual Camera control
Proceedings of the ninth ACM international conference on Multimedia - MULTIMEDIA '01, 2001Co-Authors: Xinding Sun, Jonathan Foote, Don Kimber, B S ManjunathAbstract:A system for capturing panoramic video and a novel method for corresponding compressed domain Virtual Camera control is presented. It targets applications such as classroom lectures and video conferencing. The proposed method is based on the FlyCam panoramic video system that is designed to produce high resolution and wide-angle video sequences by stitching the video pictures from multiple stationary Cameras. The panoramic video sequence is compressed into an MPEG-2 stream for delivery. The proposed method integrates region of Interest (ROI) detection, tracking, and Virtual Camera control, and works on compressed domain information only. It first detects the ROI in the P (predictive coded) picture using only the macroblock type information, It then up-samples this detection result to obtain the ROI of the whole video stream. The ROI is tracked using a Kalman filter. The Kalman filter estimation results are used for Virtual Camera control that simulates human controlled video recording. The system has no physical Camera motion and the Virtual Camera parameters are readily available for video indexing. The proposed system has been implemented for real time processing.
