Expressiveness of real-time motion captured avatars influences perceived animation realism and perceived quality of social interaction in virtual reality

Using motion capture to enhance the realism of social interaction in virtual reality (VR) is growing in popularity. However, the impact of different levels of avatar expressiveness on the user experience is not well understood. In the present study we manipulated levels of face and body expressiveness of avatars while investigating participant perceptions of animation realism and interaction quality when disclosing positive and negative experiences in VR. Moderate positive associations were observed between perceptions of animation realism and interaction quality. Post-experiment questions revealed that many of our participants (approximately 40 %) indicated the avatar with the highest face and body expressiveness as having the most realistic face and body expressions. The same proportion also indicated the avatar with the highest face and body expressiveness as being the most comforting and enjoyable avatar to interact with. Our results suggest that higher levels of face and body expressiveness are important for enhancing perceptions of realism and interaction quality within a social interaction in VR using motion capture

Cyclic animation using Partial differential Equations

YesThis work presents an efficient and fast method for achieving cyclic animation using Partial Differential Equations (PDEs). The boundary-value nature associ- ated with elliptic PDEs offers a fast analytic solution technique for setting up a framework for this type of animation. The surface of a given character is thus cre- ated from a set of pre-determined curves, which are used as boundary conditions so that a number of PDEs can be solved. Two different approaches to cyclic ani- mation are presented here. The first consists of using attaching the set of curves to a skeletal system hold- ing the animation for cyclic motions linked to a set mathematical expressions, the second one exploits the spine associated with the analytic solution of the PDE as a driving mechanism to achieve cyclic animation, which is also manipulated mathematically. The first of these approaches is implemented within a framework related to cyclic motions inherent to human-like char- acters, whereas the spine-based approach is focused on modelling the undulatory movement observed in fish when swimming. The proposed method is fast and ac- curate. Additionally, the animation can be either used in the PDE-based surface representation of the model or transferred to the original mesh model by means of a point to point map. Thus, the user is offered with the choice of using either of these two animation repre- sentations of the same object, the selection depends on the computing resources such as storage and memory capacity associated with each particular application

Enhancing Expressiveness of Speech through Animated Avatars for Instant Messaging and Mobile Phones

This thesis aims to create a chat program that allows users to communicate via an animated avatar that provides believable lip-synchronization and expressive emotion. Currently many avatars do not attempt to do lip-synchronization. Those that do are not well synchronized and have little or no emotional expression. Most avatars with lip synch use realistic looking 3D models or stylized rendering of complex models. This work utilizes images rendered in a cartoon style and lip-synchronization rules based on traditional animation. The cartoon style, as opposed to a more realistic look, makes the mouth motion more believable and the characters more appealing. The cartoon look and image-based animation (as opposed to a graphic model animated through manipulation of a skeleton or wireframe) also allows for fewer key frames resulting in faster speed with more room for expressiveness. When text is entered into the program, the Festival Text-to-Speech engine creates a speech file and extracts phoneme and phoneme duration data. Believable and fluid lip-synchronization is then achieved by means of a number of phoneme-to-image rules. Alternatively, phoneme and phoneme duration data can be obtained for speech dictated into a microphone using Microsoft SAPI and the CSLU Toolkit. Once lip synchronization has been completed, rules for non-verbal animation are added. Emotions are appended to the animation of speech in two ways: automatically, by recognition of key words and punctuation, or deliberately, by user-defined tags. Additionally, rules are defined for idle-time animation. Preliminary results indicate that the animated avatar program offers an improvement over currently available software. It aids in the understandability of speech, combines easily recognizable and expressive emotions with speech, and successfully enhances overall enjoyment of the chat experience. Applications for the program include use in cell phones for the deaf or hearing impaired, instant messaging, video conferencing, instructional software, and speech and animation synthesis

Anatomical Modelling of the Musculoskeletal System from MRI

Abstract. This paper presents a novel approach for multi-organ (mus-culoskeletal system) automatic registration and segmentation from clini-cal MRI datasets, based on discrete deformable models (simplex meshes). We reduce the computational complexity using multi-resolution forces, multi-resolution hierarchical collision handling and large simulation time steps (implicit integration scheme), allowing real-time user control and cost-efficient segmentation. Radial forces and topological constraints (at-tachments) are applied to regularize the segmentation process. Based on a medial axis constrained approximation, we efficiently characterize shapes and deformations. We validate our methods for the hip joint and the thigh (20 muscles, 4 bones) on 4 datasets: average error=1.5mm, computation time=15min.

Volumetric intelligence: A framework for the creation of interactive volumetric captured characters

Virtual simulation of human faces and facial movements has challenged media artists and computer scientists since the first realistic 3D renderings of a human face by Fred Parke in 1972. Today, a range of software and techniques are available for modelling virtual characters and their facial behavior in immersive environments, such as computer games or storyworlds. However, applying these techniques often requires large teams with multidisciplinary expertise, extensive amount of manual labor, as well as financial conditions that are not typically available for individual media artists. This thesis work demonstrates how an individual artist may create humanlike virtual characters – specifically their facial behavior – in a relatively fast and automated manner. The method is based on volumetric capturing, or photogrammetry, of a set of facial expressions from a real person using a multi-camera setup, and further applying open source and accessible 3D reconstruction and re-topology techniques and software. Furthermore, the study discusses possibilities of utilizing contemporary game engines and applications for building settings that allow real-time interaction between the user and virtual characters. The thesis documents an innovative framework for the creation of a virtual character captured from a real person, that can be presented and driven in real-time, without the need of a specialized team, high budget or intensive manual labor. This workflow is suitable for research groups, independent teams and individuals seeking for the creation of immersive and real-time experiences and experiments using virtual humanlike characters

Simulating virtual humans in networked virtual environments

In the past decade, networked virtual environments (NVEs) have been an increasingly active area of research, with the first commercial systems emerging recently. Graphical and behavioral representation of users within such systems is a particularly important issue that has lagged in development behind other issues such as network architectures and space structuring. We expose the importance of using virtual humans within these systems and provide a brief overview of several virtual human technologies used in particular for simulation of crowds. As the main technical contribution, the paper presents the integration of these technologies with the COVEN-DIVE platform, the extension of the DIVE system developed within the COVEN project. In conjunction with this, we present our contributions through the COVEN project to the MPEG-4 standard concerning the representation of virtual human

Data-driven techniques for animating virtual characters

One of the key goals of current research in data-driven computer animation is the synthesis of new motion sequences from existing motion data. This thesis presents three novel techniques for synthesising the motion of a virtual character from existing motion data and develops a framework of solutions to key character animation problems. The first motion synthesis technique presented is based on the character’s locomotion composition process. This technique examines the ability of synthesising a variety of character’s locomotion behaviours while easily specified constraints (footprints) are placed in the three-dimensional space. This is achieved by analysing existing motion data, and by assigning the locomotion behaviour transition process to transition graphs that are responsible for providing information about this process. However, virtual characters should also be able to animate according to different style variations. Therefore, a second technique to synthesise real-time style variations of character’s motion. A novel technique is developed that uses correlation between two different motion styles, and by assigning the motion synthesis process to a parameterised maximum a posteriori (MAP) framework retrieves the desire style content of the input motion in real-time, enhancing the realism of the new synthesised motion sequence. The third technique presents the ability to synthesise the motion of the character’s fingers either o↵-line or in real-time during the performance capture process. The advantage of both techniques is their ability to assign the motion searching process to motion features. The presented technique is able to estimate and synthesise a valid motion of the character’s fingers, enhancing the realism of the input motion. To conclude, this thesis demonstrates that these three novel techniques combine in to a framework that enables the realistic synthesis of virtual character movements, eliminating the post processing, as well as enabling fast synthesis of the required motion