Abstract: This paper introduces an approach to performance animation that employs video cameras and a small set of retro-reflective markers to create a low-cost, easy-to-use system that might someday be practical for home use. The low-dimensional control signals from the user's performance are supplemented by a database of pre-recorded human motion. At run time, the system automatically learns a series of local models from a set of motion capture examples that are a close match to the marker locations captured by the cameras. These local models are then used to reconstruct the motion of the user as a full-body animation. We demonstrate the power of this approach with real-time control of six different behaviors using two video cameras and a small set of retro-reflective markers. We compare the resulting animation to animation from commercial motion capture equipment with a full set of markers.

Abstract: Computer animation has tremendous potential to provide visualizations of dynamic phenomena that involve change over time (e.g., biological processes, physical phenomena, mechanical devices, and historical development). However, the research reviewed in this chapter showed that learners did not systematically take advantage of animated graphics in terms of comprehension of the underlying causal or functional model. This chapter reviewed the literature about the interface and content features that affect the potential benefits of animation over static graphics. Finally, I proposed some guidelines that designers should consider when designing multimedia instruction including animation. What Are the Animation Principle and the Interactivity Principle? In the last decade, with the rapid progression of computing capacities and the progress of graphic design technologies, multimedia learning environments have evolved from sequential static text and picture frames to increasing sophisticated visualizations. Two characteristics appear to be popular among instruction designers and practitioners: the use of animated graphics as soon as depiction of dynamic system is involved, and the capability for learners to interact with the instructional material. Conceptions of Animation Despite its extensive use in instructional material, computer animation still is not well understood. Baek and Layne (1988) defined animation as “the process of generating a series of frames containing an object or objects so that each frame appears as an alteration of the previous frame in order to show motion” (p. 132).

Abstract: Interactivity in the sense of being able to explore and navigate audio-visual scenes by freely choosing viewpoint and viewing direction, is an important key feature of new and emerging audio-visual media. This paper gives an overview of suitable technology for such applications, with a focus on international standards, which are beneficial for consumers, service providers, and manufacturers. We first give a general classification and overview of interactive scene representation formats as commonly used in computer graphics literature. Then, we describe popular standard formats for interactive three-dimensional (3-D) scene representation and creation of virtual environments, the virtual reality modeling language (VRML), and the MPEG-4 BInary Format for Scenes (BIFS) with some examples. Recent extensions to MPEG-4 BIFS, the Animation Framework eXtension (AFX), providing advanced computer graphics tools, are explained and illustrated. New technologies mainly targeted at reconstruction, modeling, and representation of dynamic real world scenes are further studied. The user shall be able to navigate photorealistic scenes within certain restrictions, which can be roughly defined as 3-D video. Omnidirectional video is an extension of the planar two-dimensional (2-D) image plane to a spherical or cylindrical image plane. Any 2-D view in any direction can be rendered from this overall recording to give the user the impression of looking around. In interactive stereo two views, one for each eye, are synthesized to provide the user with an adequate depth cue of the observed scene. Head motion parallax viewing can be supported in a certain operating range if sufficient depth or disparity data are delivered with the video data. In free viewpoint video, a dynamic scene is captured by a number of cameras. The input data are transformed into a special data representation that enables interactive navigation through the dynamic scene environment.

Abstract: This paper explores a behavior planning approach to automatically generate realistic motions for animated characters. Motion clips are abstracted as high-level behaviors and associated with a behavior finite-state machine (FSM) that defines the movement capabilities of a virtual character. During runtime, motion is generated automatically by a planning algorithm that performs a global search of the FSM and computes a sequence of behaviors for the character to reach a user-designated goal position. Our technique can generate interesting animations using a relatively small amount of data, making it attractive for resource-limited game platforms. It also scales efficiently to large motion databases, because the search performance is primarily dependent on the complexity of the behavior FSM rather than on the amount of data. Heuristic cost functions that the planner uses to evaluate candidate motions provide a flexible framework from which an animator can control character preferences for certain types of behavior. We show results of synthesized animations involving up to one hundred human and animal characters planning simultaneously in both static and dynamic environments.

Abstract: In order to gain insight into multivariate data, complex structures must be analysed and understood. Parallel coordinates is an excellent tool for visualizing this type of data but has its limitations. This paper deals with one of its main limitations - how to visualize a large number of data items without hiding the inherent structure they constitute. We solve this problem by constructing clusters and using high precision textures to represent them. We also use transfer functions that operate on the high precision textures in order to highlight different aspects of the cluster characteristics. Providing predefined transfer functions as well as the support to draw customized transfer functions makes it possible to extract different aspects of the data. We also show how feature animation can be used as guidance when simultaneously analysing several clusters. This technique makes it possible to visually represent statistical information about clusters and thus guides the user, making the analysis process more efficient.

Abstract: An animating system converts a text-based document into a sequence of animating pictures for helping a user to understand better and faster. First, the system provides interfaces for a user to build various object models, specify default rules for these object models, and construct the references for meanings and actions. Second, the system will analyze the document, extract desired information, identify various objects, and organize information. Then the system will create objects from corresponding object models and provide interfaces to modify default values and default rules and define specific values and specific rules. Further, the system will identify the meanings of words and phrases. Furthermore, the system will identify, interpolate, synchronize, and dispatch events. Finally, the system provides interface for the user to track events and particular objects.

Abstract: We present a vision-based performance interface for controlling animated human characters. The system interactively combines information about the user's motion contained in silhouettes from three viewpoints with domain knowledge contained in a motion capture database to produce an animation of high quality. Such an interactive system might be useful for authoring, for teleconferencing, or as a control interface for a character in a game. In our implementation, the user performs in front of three video cameras; the resulting silhouettes are used to estimate his orientation and body configuration based on a set of discriminative local features. Those features are selected by a machine-learning algorithm during a preprocessing step. Sequences of motions that approximate the user's actions are extracted from the motion database and scaled in time to match the speed of the user's motion. We use swing dancing, a complex human motion, to demonstrate the effectiveness of our approach. We compare our results to those obtained with a set of global features, Hu moments, and ground truth measurements from a motion capture system.

Abstract: This paper introduces spatial keyframing, a technique for performance-driven character animation. In traditional temporal keyframing, key poses are defined at specific points in time: i.e., we define a map from a set key times to the configuration space of the character and then extend this map to the entire timeline by interpolation. By contrast, in spatial keyframing key poses are defined at specific key positions in a 3D space where the character lives; the mapping from the 3D space to the configuration space is again defined by interpolation. The user controls a character by adjusting the position of a control cursor in the 3D space; the pose of the character is given as a blend of nearby key poses. The user thus can make expressive motion in real time and the resulting motion can be recorded and interpreted as an animation sequence. Although similar ideas are present in previous systems, our system is unique in that the designer can quickly design a new set of keyframes from scratch, and make an animation without motion capture data or special input devices. Our technique is especially useful for imaginary characters other than human figures because we do not rely on motion-capture data. We also introduce several applications of the basic idea and give examples showing the expressiveness of the approach.

Abstract: John Vince explains a wide range of mathematical techniques and problem-solving strategies associated with computer games, computer animation, virtual reality, CAD and other areas of computer graphics in this updated and expanded fourth edition. The first four chapters revise number sets, algebra, trigonometry and coordinate systems, which are employed in the following chapters on vectors, transforms, interpolation, 3D curves and patches, analytic geometry and barycentric coordinates. Following this, the reader is introduced to the relatively new topic of geometric algebra, and the last two chapters provide an introduction to differential and integral calculus, with an emphasis on geometry. Mathematics for Computer Graphics covers all of the key areas of the subject, including:Number setsAlgebraTrigonometryCoordinate systemsTransformsQuaternionsInterpolationCurves and surfacesAnalytic geometryBarycentric coordinatesGeometric algebraDifferential calculusIntegral calculusThis fourth edition contains over 120 worked examples and over 270 illustrations, which are central to the authors descriptive writing style. Mathematics for Computer Graphics provides a sound understanding of the mathematics required for computer graphics, giving a fascinating insight into the design of computer graphics software and setting the scene for further reading of more advanced books and technical research papers.

Abstract: This paper describes research that investigates the application of augmented reality (AR) in 3D animation of simulated construction operations. The objective is an AR-based platform that can be used together with corresponding equipment (HMD, GPS receiver, and a portable computer) to generate a mixed view of the real world and superimposed virtual simulation objects in an outdoor environment. The characteristic that distinguishes the presented work from indoor AR applications is the capability to produce real time updated output as the user moves around while applying minimum constraints over the user's position and orientation. The ability to operate independently of environmental factors (e.g. lighting conditions and terrain variations) makes the described framework a powerful tool for outdoor AR applications. This paper presents initial results and an AR platform prototype (UM-AR-GPS-ROVER) that is able to place 3D graphical objects at any desired location in outdoor augmented space.

Abstract: Traditionally, time-varying data has been visualized using snapshots of the individual time steps or an animation of the snapshots shown in a sequential manner. For larger datasets with many time-varying features, animation can be limited in its use, as an observer can only track a limited number of features over the last few frames. Visually inspecting each snapshot is not practical either for a large number of time-steps. We propose new techniques inspired from the illustration literature to convey change over time more effectively in a time-varying dataset. Speedlines are used extensively by cartoonists to convey motion, speed, or change over different panels. Flow ribbons are another technique used by cartoonists to depict motion in a single frame. Strobe silhouettes are used to depict previous positions of an object to convey the previous positions of the object to the user. These illustration-inspired techniques can be used in conjunction with animation to convey change over time.

Abstract: Dynamic three-dimensional (3D) animation can be of significant value in improving the verification validation, and communication of discrete-event simulation (DES) models of construction operations, which in turn can make the models more credible and thus useful in operations planning and decision making. This paper presents research that led to the design and implementation of practical 3D animation methods to visualize multiply-articulated construction equipment in 3D animations of simulated construction operations. Using principles of forward and inverse kinematics, the writers designed and implemented generic virtual pieces of articulated construction equipment that accept task-level instructions from external software processes. DES models can configure and instantiate specific pieces of such equipment and instruct them to perform construction tasks using simple parametric text statements that embody a construction work-like terminology. Once instructed to perform specific tasks (e.g., load soil), th...

Abstract: In this paper we introduce a video-based representation for free viewpoint visualization and motion control of 3D character models created from multiple view video sequences of real people. Previous approaches to video-based rendering provide no control of scene dynamics to manipulate, retarget, and create new 3D content from captured scenes. Here we contribute a new approach, combining image based reconstruction and video-based animation to allow controlled animation of people from captured multiple view video sequences. We represent a character as a motion graph of free viewpoint video motions for animation control. We introduce the use of geometry videos to represent reconstructed scenes of people for free viewpoint video rendering. We describe a novel spherical matching algorithm to derive global surface to surface correspondence in spherical geometry images for motion blending and the construction of seamless transitions between motion sequences. Finally, we demonstrate interactive video-based character animation with real-time rendering and free viewpoint visualization. This approach synthesizes highly realistic character animations with dynamic surface shape and appearance captured from multiple view video of people.

Abstract: Embodiments of the present invention provide methods and apparatus wherein physics models are integrated with motion capture animation to allow for variability in animations, dynamic response, such as animating events different from those for which motion capture data was obtained, including changes in character purpose and collisions. The physical model may include sets of internal forces and/or external forces. To facilitate the integration of mo-cap animation data with physics models, mo-cap animation data is played back using forces on physical models rather than directly setting joint angles or positions in a graphical skeleton, which allows the animation to be dynamically altered in real-time in a physically realistic manner by external forces and impulses.

Abstract: We introduce the Dynamic Animation and Control Environment (DANCE) as a publicly available simulation platform for research and teaching DANCE is an open and extensible simulation framework and rapid prototyping environment for computer animation The main focus of the DANCE platform is the development of physically-based controllers for articulated figures In this paper we (a) present the architecture and potential applications of DANCE as a research tool, and (b) discuss lessons learned in developing a large framework for animation

Abstract: We present a novel constraint-based keyframe extraction technique, Key Probe. Based on animator-specified constraints, the method converts a skeleton-based motion or animated mesh to a keyframe-based representation. In contrast to previous curve simplification or clustering methods, we cast the keyframe extraction problem as a constrained matrix factorization problem and solve the problem based on the least-squares optimization technique. The extracted keyframes have two uses: they could be used for browsing or they may be blended to reconstruct all other frames of an animation. Our approach is general and suitable for both rigid-body and soft-body animations. Experiments on various types of animation examples show that the proposed method produces remarkable results in terms of quality and compression ratio. Empirical tests also show that our algorithm consistently offers better efficiency than those by principal component analysis (PCA) and independent component analysis (ICA).

Abstract: This paper describes a user study conducted to evaluate the use of smooth animated transitions between directories in a three-dimensional, tree-map visualization. We looked specifically at the task of returning to a previously visited directory after either an animated or instantaneous return to the root location. The results of the study show that animation is a double-edged sword. Even though users take more shortcuts, they also make more severe navigational errors. It seems as though the promise of a more direct route to the target directory, which animation provides, somehow precludes users who navigate incorrectly from applying a successful recovery strategy.

Abstract: Interactive generation of reactive motions for virtual humans as they are hit, pushed and pulled are very important to many applications, such as computer games. In this paper, we propose a new method to simulate reactive motions during arbitrary bipedal activities, such as standing, walking or running. It is based on momentum based inverse kinematics and motion blending. When generating the animation, the user first imports the primary motion to which the perturbation is to be applied to. According to the condition of the impact, the system selects a reactive motion from the database of pre-captured stepping and reactive motions. It then blends the selected motion into the primary motion using momentum-based inverse kinematics. Since the reactive motions can be edited in real-time, the criteria for motion search can be much relaxed than previous methods, and therefore, the computational cost for motion search can be reduced. Using our method, it is possible to generate reactive motions by applying external perturbations to the characters at arbitrary moment while they are performing some actions. Copyright # 2005 John Wiley & Sons, Ltd.

Abstract: We synchronize background music with an animation by changing the timing of both, an approach which minimizes the damage to either. Starting from a MIDI le and motion data, feature points are extracted from both sources, paired, and then synchronized using dynamic programming to time-scale the music and to timewarp the motion. We also introduce the music graph, a directed graph which encapsulates connections between many short music sequences. By traversing a music graph we can generate large amounts of new background music, in which we expect to nd a sequence which matches the motion better than the original music.

Abstract: A real-time system for capturing humans in 3D and placing them into a mixed reality environment is presented in this paper. Nine cameras surrounding her capture the subject. Looking through a head-mounted-display with a camera in front pointing at a marker, the user can see the 3D image of this subject overlaid onto a mixed reality scene. The 3D images of the subject viewed from this viewpoint are constructed using a robust and fast shape-from-silhouette algorithm. The paper also presents several techniques to produce good quality and speed up the whole system. The frame rate of our system is around 25 fps using only standard Intel processor-based personal computers. Besides a remote live 3D conferencing and collaborating system, we also describe an application of the system in art and entertainment, named Magic Land, which is a mixed reality environment where captured avatars of human and 3D computer generated virtual animations can form an interactive story and play with each other. This system demonstrates many technologies in human computer interaction: mixed reality, tangible interaction, and 3D communication. The result of the user study not only emphasizes the benefits, but also addresses some issues of these technologies.

Abstract: We present a technique to extract motion parameters of a human figure from a single video stream. Our goal is to prototype motion synthesis rapidly for game design and animation applications. For example, our approach is especially useful in situations where motion capture systems are restricted in their usefulness given the various required instrumentation. Similarly, our approach can be used to synthesize motion from archival footage. By extracting the silhouette of the foreground figure and using a model-based approach, the problem is re-formulated as a local, optimized search of the pose space. The pose space consists of 6 rigid body transformation parameters plus the internal joint angles of the figure. The silhouette of the figure from the captured video is compared against the silhouette of a synthetic figure using a pixel-by-pixel, distance-based cost function to evaluate goodness-of-fit. For a single video stream, this is not without problems. Occlusion and ambiguities arising from the use of a single view often cause spurious reconstruction of the captured motion. By using temporal coherence, physical constraints, and knowledge of the anatomy, a viable pose sequence can be reconstructed for many live-action sequences.

Abstract: A method and system for interactive communication in sign language using computer animation. In one aspect, a user interface is provided with a first activity area and a second activity area. A three-dimensional avatar configured to communicate using sign language is displayed between the first activity area and the second activity area. In response to the user selection of a respective one of the activity areas, the avatar is directed to sign an expression associated with the selected activity area. In another aspect, a method of teaching mathematics using sign language is provided. According to another aspect, a method of animating a signed communication is provided. In another aspect, a method of creating an animation of a sign language expression is provided.

Abstract: A method for controlling an animation timeline comprising the steps of determining the three-dimensional assets of the data in the animation timeline and, if required, converting the data dimensionally, cleaning up the data in the animation timeline, building a mesh for the data in the animation timeline, setting up a scene for the data in the animation timeline, animating the scene for the data for creating animated data, publishing the three-dimensional content of the scenes for the data in the animation timeline, creating an appropriate interface for the data in the animation timeline, synchronizing a soundtrack to the animated data, incorporating additional features to the animated data, and combining the animated data such that the data is mixed, HTML prepared and Java script adapted whereby the method provides a self-contained object.

Abstract: Crowd animation and simulation have been widely studied over the last decade for many purposes: populating collaborative virtual environments, entertainment and special effects industry and finally simulating behaviors and motion of people in emergency situations for safety systems. This last topic is addressed in this paper. We propose an original enhancement of a well known physics-based animation model which allows to consider influence of gaseous phenomena such as smoke or toxic gases in the behavior of the crowd. In order to get real time performances we also propose an implementation of this framework on modern graphics hardware, which allows to simulate crowds of thousands individuals at interactive framerate.

Abstract: The art. The craft. The business. Animation Writing and Development takes students and animation professionals alike through the process of creating original characters, developing a television series, feature, or multimedia project, and writing professional premises, outlines and scripts. It covers the process of developing presentation bibles and pitching original projects as well as ideas for episodes of shows already on the air. Animation Writing and Development includes chapters on animation history, on child development (writing for kids), and on storyboarding. It gives advice on marketing and finding work in the industry. It provides exercises for students as well as checklists for professionals polishing their craft. This is a guide to becoming a good writer as well as a successful one.

Abstract: Various embodiments of the invention provide novel software, systems and methods for animation and/or filmmaking. In a set of embodiments, for example, a client-server system provides the ability to control various aspects of a live-action and/or an animated scene, including cameras and/or light sources (either real and/or virtual), animated characters, and other objects. This can include, merely by way of example, moving cameras, light and/or the like, as well as rendering animated objects (e.g., based on movements of the objects themselves and/or based on movements of cameras, lights, etc.).

Abstract: The ACM SIGGRAPH/Eurographics Symposium on Computer Animation (SCA) continues to be a leading scientific meeting devoted exclusively to computer animation. The Symposium attracts high-quality papers and provides an opportunity for researchers in the area of computer animation to meet, share ideas, and discuss emerging directions for the field. This year the Fifth SCA was co-located with the ACM SIGGRAPH 2005 Conference in Los Angeles, California, and it was held just prior to the main conference.These proceedings contain 35 papers selected from 100 submissions. The exceptional quality of the submitted papers made the final selection very difficult. Each paper was reviewed by at least 4 members of the international program committee and external reviewers. The reviewing process was double blind. As in the previous year, the process included a discussion phase during which all reviewers of a paper could discuss it anonymously on-line. We believe that the discussions helped the reviewers to improve the quality of their evaluations. The accepted papers cover a variety of topics, including motion capture and editing, faces and hair, deformable models, fluids, natural phenomena, artificial intelligence for animation, motion planning and crowds, interfaces and interactive techniques, rigging and hands, non-photorealistic animation and compression, performance animation and motion quality.The Symposium continues to accept posters and demos that present promising work in progress. This year we added a special session to the Symposium in which the authors of posters gave a short presentation of their work. There was also be a reception during which the posters were on display and their authors were available for discussions. In addition to the posters that were submitted, we also invited several promising papers that were not accepted to the papers track to be presented as posters.

Abstract: This paper describes an Interactive Modeling, Simulation, Animation, and Real-Time Control (MoSART) Environment that is useful for controls education and research. The described MoSART environment is shown to be useful for analyzing, designing, visualizing, and evaluating control systems for a class of "cart-pendulum" electromechanical systems. The environment-referred to as Cart-Pendulum Control3D-Lab-is based on Microsoft Windows, Visual C++, Direct-3D, and MATLAB/Simulink. The environment can be used as a stand-alone application or together with MATLAB, Simulink, and toolboxes. When used as a stand-alone application, a friendly graphical user interface permits easy interaction. Users may select (via pull-down menus) systems, dynamical models, control laws, exogenous signals (including joystick inputs) and associated parameters, initial conditions, integration routines, and associated parameters. When used with MATLAB, Simulink, and toolboxes, the previously mentioned nominal features are significantly enhanced. In either case, the interface permits users to access the following (via pull-down menus): animation models, mesh properties, texture and lighting models, system-specific visual indicators, graphics to be displayed, animation/data display/storage rates, simulation control buttons, and extensive documentation. When Simulink is present, users can exploit extensive visualization and three-dimensional (3-D) animation features through provided and/or user-generated Simulink diagrams. This capability makes the developed environment very extensible with respect to mathematical models and control laws. In addition, users may readily export simulation data to MATLAB/toolboxes for postprocessing and further analysis. The environment also contains a suite of well-documented (easy-to-modify) models and control laws that are implemented within the provided Simulink block diagrams. Provided (special) blocks enable animation, joystick inputs, and (near) real-time simulation and animation (when possible). (Near real-time-or faster-than-real-time-simulation and animation are possible whenever the mathematical and animation models are sufficiently simple and data manipulation requirements, e.g. storage and display, are sufficiently mild. For the systems considered, (near) real-time simulation and animation is readily achievable.) Associated with each block diagram are system-specific, menu-accessed m-files that permit detailed analysis and design. A hardware module permits real-time control of actual hardware experiments. The developed environment is shown to be a valuable tool for enhancing both controls education in a variety of classes as well as research. Examples are presented to illustrate the utility of the environment.