Evaluation of user response by using visual cues designed to direct the viewer's attention to the main scene in an immersive environment

Today the visualization of 360-degree videos has become a means to live immersive experiences.. However, an important challenge to overcome is how to guide the viewers attention to the video main scene, without interrupting the immersion experience and the narrative thread. To meet this challenge, we have developed a software prototype to assess three approaches: Arrows, Radar and Auto Focus. These are based on visual guidance cues used in first person shooter games such as: Radar-Sonar, Radar-Compass and Arrows. In the study a questionnaire was made to evaluate the comprehension of the narrative, the user's perspective with respect to the design of the visual cues and the usability of the system. In addition, data was collected on the movement of the user's head, in order to analyze the focus of attention. The study used statistical methods to perform the analysis, the results show that the participants who used some visual cue (any of these) showed significant improvements compared to the control group (without using visual cues) in finding the main scene. With respect to narrative compression, significant improvements were obtained in the user group that used Radar and Auto Focus compared to the control group

Expanding the bounds of seated virtual workspaces

Mixed Reality (MR), Augmented Reality (AR) and Virtual Reality (VR) headsets can improve upon existing physical multi-display environments by rendering large, ergonomic virtual display spaces whenever and wherever they are needed. However, given the physical and ergonomic limitations of neck movement, users may need assistance to view these display spaces comfortably. Through two studies, we developed new ways of minimising the physical effort and discomfort of viewing such display spaces. We first explored how the mapping between gaze angle and display position could be manipulated, helping users view wider display spaces than currently possible within an acceptable and comfortable range of neck movement. We then compared our implicit control of display position based on head orientation against explicit user control, finding significant benefits in terms of user preference, workload and comfort for implicit control. Our novel techniques create new opportunities for productive work by leveraging MR headsets to create interactive wide virtual workspaces with improved comfort and usability. These workspaces are flexible and can be used on-the-go, e.g., to improve remote working or make better use of commuter journeys

Challenges in passenger use of mixed reality headsets in cars and other transportation

This paper examines key challenges in supporting passenger use of augmented and virtual reality headsets in transit. These headsets will allow passengers to break free from the restraints of physical displays placed in constrained environments such as cars, trains and planes. Moreover, they have the potential to allow passengers to make better use of their time by making travel more productive and enjoyable, supporting both privacy and immersion. However, there are significant barriers to headset usage by passengers in transit contexts. These barriers range from impediments that would entirely prevent safe usage and function (e.g. motion sickness) to those that might impair their adoption (e.g. social acceptability). We identify the key challenges that need to be overcome and discuss the necessary resolutions and research required to facilitate adoption and realize the potential advantages of using mixed reality headsets in transit

Narratives of ocular experience in interactive 360° environments

The purpose of this research project was to examine how immersive digital virtual technologies have the potential to expand the genre of interactive film into new forms of audience engagement and narrative production. Aside from addressing the limitations of interactive film, I have explored how interactive digital narratives can be reconfigured in the wake of immersive media. My contribution to knowledge stems from using a transdisciplinary synthesis of the interactive systems in film and digital media art, which is embodied in the research framework and theoretical focal point that I have titled Cynematics (chapter 2). Using a methodology that promotes iterative experimentation I developed a series of works that allowed me to practically explore the limitations of interactive film systems that involve non-haptic user interaction. This is evidenced in the following series of works: Virtual Embodiment, Narrative Maze, Eye Artefact Interactions and Routine Error - all of which are discussed in chapter 4 of this thesis. Each of these lab experiments collectively build towards the development of novel interactive 360° film practices. Funneling my research towards these underexplored processes I focused on virtual gaze interaction (chapters 4-6), aiming to define and historically contextualise this system of interaction, whilst critically engaging with it through my practice. It is here that gaze interaction is cemented as the key focus of this thesis. The potential of interactive 360° film is explored through the creation of three core pieces of practice, which are titled as follows: Systems of Seeing (chapter 5), Mimesis (chapter 6), Vanishing Point (chapter 7). Alongside the close readings in these chapters and the theoretical developments explored in each are the interaction designs included in the appendix of the thesis. These provide useful context for readers unable to experience these site-specific installations as virtual reality applications. After creating these systems, I established terms to theoretically unpack some of the processes occurring within them. These include Datascape Mediation (chapter 2), which frames agency as a complex entanglement built on the constantly evolving relationships between human and machine - and Live-Editing Practice (chapter 7), which aims to elucidate how the interactive 360° film practice designed for this research leads to new way of thinking about how we design, shoot and interact with 360° film. Reflecting on feedback from exhibiting Mimesis I decided to define and evaluate the key modes of virtual gaze interaction, which led to the development of a chapter and concept referred to as The Reticle Effect (chapter 6). This refers to how a visual overlay that is used to represent a user's line of sight not only shapes their experience of the work, but also dictates their perception of genre. To navigate this, I combined qualitative and quantitative analysis to explore user responses to four different types of gaze interaction. In preparing to collect this data I had to articulate these different types of interaction, which served to demarcate the difference between each of these types of gaze interaction. Stemming from this I used questionnaires, thematic analysis and data visualisation to explore the use and response to these systems. The results of this not only supports the idea of the reticle effect, but also gives insight into how these different types of virtual gaze interaction shape whether these works are viewed as games or as types of interactive film. The output of this allowed me to further expand on interactive 360° film as a genre of immersive media and move beyond the realm of interactive film into new technological discourses, which serves to validate the nascent, yet expansive reach of interactive 360° film as a form of practice. The thesis is concluded by framing this research within the wider discourse of posthuman theory as given that the technologies of immersive media perpetuate a state of extended human experience - how we interact and consider the theories that surround these mediums needs to be considered in the same way. The practice and theory developed throughout this thesis contribute to this discourse and allow for new ways of considering filmic language in the wake of interactive 360° film practice

Towards Naturalistic Interfaces of Virtual Reality Systems

Interaction plays a key role in achieving realistic experience in virtual reality (VR). Its realization depends on interpreting the intents of human motions to give inputs to VR systems. Thus, understanding human motion from the computational perspective is essential to the design of naturalistic interfaces for VR. This dissertation studied three types of human motions, including locomotion (walking), head motion and hand motion in the context of VR. For locomotion, the dissertation presented a machine learning approach for developing a mechanical repositioning technique based on a 1-D treadmill for interacting with a unique new large-scale projective display, called the Wide-Field Immersive Stereoscopic Environment (WISE). The usability of the proposed approach was assessed through a novel user study that asked participants to pursue a rolling ball at variable speed in a virtual scene. In addition, the dissertation studied the role of stereopsis in avoiding virtual obstacles while walking by asking participants to step over obstacles and gaps under both stereoscopic and non-stereoscopic viewing conditions in VR experiments. In terms of head motion, the dissertation presented a head gesture interface for interaction in VR that recognizes real-time head gestures on head-mounted displays (HMDs) using Cascaded Hidden Markov Models. Two experiments were conducted to evaluate the proposed approach. The first assessed its offline classification performance while the second estimated the latency of the algorithm to recognize head gestures. The dissertation also conducted a user study that investigated the effects of visual and control latency on teleoperation of a quadcopter using head motion tracked by a head-mounted display. As part of the study, a method for objectively estimating the end-to-end latency in HMDs was presented. For hand motion, the dissertation presented an approach that recognizes dynamic hand gestures to implement a hand gesture interface for VR based on a static head gesture recognition algorithm. The proposed algorithm was evaluated offline in terms of its classification performance. A user study was conducted to compare the performance and the usability of the head gesture interface, the hand gesture interface and a conventional gamepad interface for answering Yes/No questions in VR. Overall, the dissertation has two main contributions towards the improvement of naturalism of interaction in VR systems. Firstly, the interaction techniques presented in the dissertation can be directly integrated into existing VR systems offering more choices for interaction to end users of VR technology. Secondly, the results of the user studies of the presented VR interfaces in the dissertation also serve as guidelines to VR researchers and engineers for designing future VR systems

Applying image processing techniques to pose estimation and view synthesis.

Fung Yiu-fai Phineas.Thesis (M.Phil.)--Chinese University of Hong Kong, 1999.Includes bibliographical references (leaves 142-148).Abstracts in English and Chinese.Chapter 1 --- Introduction --- p.1Chapter 1.1 --- Model-based Pose Estimation --- p.3Chapter 1.1.1 --- Application - 3D Motion Tracking --- p.4Chapter 1.2 --- Image-based View Synthesis --- p.4Chapter 1.3 --- Thesis Contribution --- p.7Chapter 1.4 --- Thesis Outline --- p.8Chapter 2 --- General Background --- p.9Chapter 2.1 --- Notations --- p.9Chapter 2.2 --- Camera Models --- p.10Chapter 2.2.1 --- Generic Camera Model --- p.10Chapter 2.2.2 --- Full-perspective Camera Model --- p.11Chapter 2.2.3 --- Affine Camera Model --- p.12Chapter 2.2.4 --- Weak-perspective Camera Model --- p.13Chapter 2.2.5 --- Paraperspective Camera Model --- p.14Chapter 2.3 --- Model-based Motion Analysis --- p.15Chapter 2.3.1 --- Point Correspondences --- p.16Chapter 2.3.2 --- Line Correspondences --- p.18Chapter 2.3.3 --- Angle Correspondences --- p.19Chapter 2.4 --- Panoramic Representation --- p.20Chapter 2.4.1 --- Static Mosaic --- p.21Chapter 2.4.2 --- Dynamic Mosaic --- p.22Chapter 2.4.3 --- Temporal Pyramid --- p.23Chapter 2.4.4 --- Spatial Pyramid --- p.23Chapter 2.5 --- Image Pre-processing --- p.24Chapter 2.5.1 --- Feature Extraction --- p.24Chapter 2.5.2 --- Spatial Filtering --- p.27Chapter 2.5.3 --- Local Enhancement --- p.31Chapter 2.5.4 --- Dynamic Range Stretching or Compression --- p.32Chapter 2.5.5 --- YIQ Color Model --- p.33Chapter 3 --- Model-based Pose Estimation --- p.35Chapter 3.1 --- Previous Work --- p.35Chapter 3.1.1 --- Estimation from Established Correspondences --- p.36Chapter 3.1.2 --- Direct Estimation from Image Intensities --- p.49Chapter 3.1.3 --- Perspective-3-Point Problem --- p.51Chapter 3.2 --- Our Iterative P3P Algorithm --- p.58Chapter 3.2.1 --- Gauss-Newton Method --- p.60Chapter 3.2.2 --- Dealing with Ambiguity --- p.61Chapter 3.2.3 --- 3D-to-3D Motion Estimation --- p.66Chapter 3.3 --- Experimental Results --- p.68Chapter 3.3.1 --- Synthetic Data --- p.68Chapter 3.3.2 --- Real Images --- p.72Chapter 3.4 --- Discussions --- p.73Chapter 4 --- Panoramic View Analysis --- p.76Chapter 4.1 --- Advanced Mosaic Representation --- p.76Chapter 4.1.1 --- Frame Alignment Policy --- p.77Chapter 4.1.2 --- Multi-resolution Representation --- p.77Chapter 4.1.3 --- Parallax-based Representation --- p.78Chapter 4.1.4 --- Multiple Moving Objects --- p.79Chapter 4.1.5 --- Layers and Tiles --- p.79Chapter 4.2 --- Panorama Construction --- p.79Chapter 4.2.1 --- Image Acquisition --- p.80Chapter 4.2.2 --- Image Alignment --- p.82Chapter 4.2.3 --- Image Integration --- p.88Chapter 4.2.4 --- Significant Residual Estimation --- p.89Chapter 4.3 --- Advanced Alignment Algorithms --- p.90Chapter 4.3.1 --- Patch-based Alignment --- p.91Chapter 4.3.2 --- Global Alignment (Block Adjustment) --- p.92Chapter 4.3.3 --- Local Alignment (Deghosting) --- p.93Chapter 4.4 --- Mosaic Application --- p.94Chapter 4.4.1 --- Visualization Tool --- p.94Chapter 4.4.2 --- Video Manipulation --- p.95Chapter 4.5 --- Experimental Results --- p.96Chapter 5 --- Panoramic Walkthrough --- p.99Chapter 5.1 --- Problem Statement and Notations --- p.100Chapter 5.2 --- Previous Work --- p.101Chapter 5.2.1 --- 3D Modeling and Rendering --- p.102Chapter 5.2.2 --- Branching Movies --- p.103Chapter 5.2.3 --- Texture Window Scaling --- p.104Chapter 5.2.4 --- Problems with Simple Texture Window Scaling --- p.105Chapter 5.3 --- Our Walkthrough Approach --- p.106Chapter 5.3.1 --- Cylindrical Projection onto Image Plane --- p.106Chapter 5.3.2 --- Generating Intermediate Frames --- p.108Chapter 5.3.3 --- Occlusion Handling --- p.114Chapter 5.4 --- Experimental Results --- p.116Chapter 5.5 --- Discussions --- p.116Chapter 6 --- Conclusion --- p.121Chapter A --- Formulation of Fischler and Bolles' Method for P3P Problems --- p.123Chapter B --- Derivation of z1 and z3 in terms of z2 --- p.127Chapter C --- Derivation of e1 and e2 --- p.129Chapter D --- Derivation of the Update Rule for Gauss-Newton Method --- p.130Chapter E --- Proof of (λ1λ2-λ 4）>〉0 --- p.132Chapter F --- Derivation of φ and hi --- p.133Chapter G --- Derivation of w1j to w4j --- p.134Chapter H --- More Experimental Results on Panoramic Stitching Algorithms --- p.138Bibliography --- p.14

Fusing Multimedia Data Into Dynamic Virtual Environments

In spite of the dramatic growth of virtual and augmented reality (VR and AR) technology, content creation for immersive and dynamic virtual environments remains a significant challenge. In this dissertation, we present our research in fusing multimedia data, including text, photos, panoramas, and multi-view videos, to create rich and compelling virtual environments. First, we present Social Street View, which renders geo-tagged social media in its natural geo-spatial context provided by 360° panoramas. Our system takes into account visual saliency and uses maximal Poisson-disc placement with spatiotemporal filters to render social multimedia in an immersive setting. We also present a novel GPU-driven pipeline for saliency computation in 360° panoramas using spherical harmonics (SH). Our spherical residual model can be applied to virtual cinematography in 360° videos. We further present Geollery, a mixed-reality platform to render an interactive mirrored world in real time with three-dimensional (3D) buildings, user-generated content, and geo-tagged social media. Our user study has identified several use cases for these systems, including immersive social storytelling, experiencing the culture, and crowd-sourced tourism. We next present Video Fields, a web-based interactive system to create, calibrate, and render dynamic videos overlaid on 3D scenes. Our system renders dynamic entities from multiple videos, using early and deferred texture sampling. Video Fields can be used for immersive surveillance in virtual environments. Furthermore, we present VRSurus and ARCrypt projects to explore the applications of gestures recognition, haptic feedback, and visual cryptography for virtual and augmented reality. Finally, we present our work on Montage4D, a real-time system for seamlessly fusing multi-view video textures with dynamic meshes. We use geodesics on meshes with view-dependent rendering to mitigate spatial occlusion seams while maintaining temporal consistency. Our experiments show significant enhancement in rendering quality, especially for salient regions such as faces. We believe that Social Street View, Geollery, Video Fields, and Montage4D will greatly facilitate several applications such as virtual tourism, immersive telepresence, and remote education

Single View Modeling and View Synthesis

This thesis develops new algorithms to produce 3D content from a single camera. Today, amateurs can use hand-held camcorders to capture and display the 3D world in 2D, using mature technologies. However, there is always a strong desire to record and re-explore the 3D world in 3D. To achieve this goal, current approaches usually make use of a camera array, which suffers from tedious setup and calibration processes, as well as lack of portability, limiting its application to lab experiments. In this thesis, I try to produce the 3D contents using a single camera, making it as simple as shooting pictures. It requires a new front end capturing device rather than a regular camcorder, as well as more sophisticated algorithms. First, in order to capture the highly detailed object surfaces, I designed and developed a depth camera based on a novel technique called light fall-off stereo (LFS). The LFS depth camera outputs color+depth image sequences and achieves 30 fps, which is necessary for capturing dynamic scenes. Based on the output color+depth images, I developed a new approach that builds 3D models of dynamic and deformable objects. While the camera can only capture part of a whole object at any instance, partial surfaces are assembled together to form a complete 3D model by a novel warping algorithm. Inspired by the success of single view 3D modeling, I extended my exploration into 2D-3D video conversion that does not utilize a depth camera. I developed a semi-automatic system that converts monocular videos into stereoscopic videos, via view synthesis. It combines motion analysis with user interaction, aiming to transfer as much depth inferring work from the user to the computer. I developed two new methods that analyze the optical flow in order to provide additional qualitative depth constraints. The automatically extracted depth information is presented in the user interface to assist with user labeling work. In this thesis, I developed new algorithms to produce 3D contents from a single camera. Depending on the input data, my algorithm can build high fidelity 3D models for dynamic and deformable objects if depth maps are provided. Otherwise, it can turn the video clips into stereoscopic video

Computer Game Innovation

Faculty of Technical Physics, Information Technology and Applied Mathematics. Institute of Information TechnologyWydział Fizyki Technicznej, Informatyki i Matematyki Stosowanej. Instytut InformatykiThe "Computer Game Innovations" series is an international forum designed to enable the exchange of knowledge and expertise in the field of video game development. Comprising both academic research and industrial needs, the series aims at advancing innovative industry-academia collaboration. The monograph provides a unique set of articles presenting original research conducted in the leading academic centres which specialise in video games education. The goal of the publication is, among others, to enhance networking opportunities for industry and university representatives seeking to form R&D partnerships. This publication covers the key focus areas specified in the GAMEINN sectoral programme supported by the National Centre for Research and Development