A mixed reality telepresence system for collaborative space operation

This paper presents a Mixed Reality system that results from the integration of a telepresence system and an application to improve collaborative space exploration. The system combines free viewpoint video with immersive projection technology to support non-verbal communication, including eye gaze, inter-personal distance and facial expression. Importantly, these can be interpreted together as people move around the simulation, maintaining natural social distance. The application is a simulation of Mars, within which the collaborators must come to agreement over, for example, where the Rover should land and go. The first contribution is the creation of a Mixed Reality system supporting contextualization of non-verbal communication. Tw technological contributions are prototyping a technique to subtract a person from a background that may contain physical objects and/or moving images, and a light weight texturing method for multi-view rendering which provides balance in terms of visual and temporal quality. A practical contribution is the demonstration of pragmatic approaches to sharing space between display systems of distinct levels of immersion. A research tool contribution is a system that allows comparison of conventional authored and video based reconstructed avatars, within an environment that encourages exploration and social interaction. Aspects of system quality, including the communication of facial expression and end-to-end latency are reported

Virtual Valcamonica: collaborative exploration of prehistoric petroglyphs and their surrounding environment in multi-user virtual reality

In this paper, we present a novel, multi-user, virtual reality environment for the interactive, collaborative 3D analysis of large 3D scans and the technical advancements that were necessary to build it: a multi-view rendering system for large 3D point clouds, a suitable display infrastructure and a suite of collaborative 3D interaction techniques. The cultural heritage site of Valcamonica in Italy with its large collection of prehistoric rock-art served as an exemplary use case for evaluation. The results show that our output-sensitive level-of-detail rendering system is capable of visualizing a 3D dataset with an aggregate size of more than 14 billion points at interactive frame rates. The system design in this exemplar application results from close exchange with a small group of potential users: archaeologists with expertise in rock-art and allows them to explore the prehistoric art and its spatial context with highly realistic appearance. A set of dedicated interaction techniques was developed to facilitate collaborative visual analysis. A multi-display workspace supports the immediate comparison of geographically distributed artifacts. An expert review of the final demonstrator confirmed the potential for added value in rock-art research and the usability of our collaborative interaction techniques

Toward hyper-realistic and interactive social VR experiences in live TV scenarios

© 2022 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Social Virtual Reality (VR) allows multiple distributed users getting together in shared virtual environments to socially interact and/or collaborate. This article explores the applicability and potential of Social VR in the broadcast sector, focusing on a live TV show use case. For such a purpose, a novel and lightweight Social VR platform is introduced. The platform provides three key outstanding features compared to state-of-the-art solutions. First, it allows a real-time integration of remote users in shared virtual environments, using realistic volumetric representations and affordable capturing systems, thus not relying on the use of synthetic avatars. Second, it supports a seamless and rich integration of heterogeneous media formats, including 3D scenarios, dynamic volumetric representation of users and (live/stored) stereoscopic 2D and 180º/360º videos. Third, it enables low-latency interaction between the volumetric users and a video-based presenter (Chroma keying), and a dynamic control of the media playout to adapt to the session’s evolution. The production process of an immersive TV show to be able to evaluate the experience is also described. On the one hand, the results from objective tests show the satisfactory performance of the platform. On the other hand, the promising results from user tests support the potential impact of the presented platform, opening up new opportunities in the broadcast sector, among others.This work has been partially funded by the European Union’s Horizon 2020 program, under agreement nº 762111 (VRTogether project), and partially by ACCIÓ, under agreement COMRDI18-1-0008 (ViVIM project). Work by Mario Montagud has been additionally funded by the Spanish Ministry of Science, Innovation and Universities with a Juan de la Cierva – Incorporación grant (reference IJCI-2017-34611). The authors would also like to thank the EU H2020 VRTogether project consortium for their relevant and valuable contributions.Peer ReviewedPostprint (author's final draft

Enhanced life-size holographic telepresence framework with real-time three-dimensional reconstruction for dynamic scene

Three-dimensional (3D) reconstruction has the ability to capture and reproduce 3D representation of a real object or scene. 3D telepresence allows the user to feel the presence of remote user that was remotely transferred in a digital representation. Holographic display is one of alternatives to discard wearable hardware restriction, it utilizes light diffraction to display 3D images to the viewers. However, to capture a real-time life-size or a full-body human is still challenging since it involves a dynamic scene. The remaining issue arises when dynamic object to be reconstructed is always moving and changes shapes and required multiple capturing views. The life-size data captured were multiplied exponentially when working with more depth cameras, it can cause the high computation time especially involving dynamic scene. To transfer high volume 3D images over network in real-time can also cause lag and latency issue. Hence, the aim of this research is to enhance life-size holographic telepresence framework with real-time 3D reconstruction for dynamic scene. There are three stages have been carried out, in the first stage the real-time 3D reconstruction with the Marching Square algorithm is combined during data acquisition of dynamic scenes captured by life-size setup of multiple Red Green Blue-Depth (RGB-D) cameras. Second stage is to transmit the data that was acquired from multiple RGB-D cameras in real-time and perform double compression for the life-size holographic telepresence. The third stage is to evaluate the life-size holographic telepresence framework that has been integrated with the real-time 3D reconstruction of dynamic scenes. The findings show that by enhancing life-size holographic telepresence framework with real-time 3D reconstruction, it has reduced the computation time and improved the 3D representation of remote user in dynamic scene. By running the double compression for the life-size holographic telepresence, 3D representations in life-size is smooth. It has proven can minimize the delay or latency during acquired frames synchronization in remote communications

Video based reconstruction system for mixed reality environments supporting contextualised non-verbal communication and its study

This Thesis presents a system to capture, reconstruct and render the three-dimensional form of people and objects of interest in such detail that the spatial and visual aspects of non-verbal behaviour can be communicated.The system supports live distribution and simultaneous rendering in multiple locations enabling the apparent teleportation of people and objects. Additionally, the system allows for the recording of live sessions and their playback in natural time with free-viewpoint.It utilises components of a video based reconstruction and a distributed video implementation to create an end-to-end system that can operate in real-time and on commodity hardware.The research addresses the specific challenges of spatial and colour calibration, segmentation and overall system architecture to overcome technical barriers, the requirement of domain specific knowledge to setup and generate avatars to a consistent high quality.Applications of the system include, but are not limited to, telepresence, where the computer generated avatars used in Immersive Collaborative Virtual Environments can be replaced with ones that are faithful of the people they represent and supporting researchers in their study of human communication such as gaze, inter-personal distance and facial expression.The system has been adopted in other research projects and is integrated with a mixed reality application where, during a live linkup, a three-dimensional avatar is streamed to multiple end-points across different countries

Visuomotor Rotation Adaptation and Workspace Manipulation: A Behavioral and Cognitive Emphasis

This is a three-study dissertation in which we aimed to broaden our knowledge of the mechanisms contributing to a 45° clockwise visuomotor adaptation by including variations in workspace. We provide behavioral and in one study physiological outcomes as evidence to support our conclusions. In the first experiment, we observed the adaptation of movement parameters such as pathlength, movement time, resultant velocity, and normalized jerk across groups trained with rotated visual feedback with both the left and right hands. Workspace location and hand differentially affected movement trajectory length. The group that practiced the task with their nondominant, left hand showed larger after-effects, thus deviations in pathlength and initial direction error than those who practiced with their right hand. We also observed the transfer of pathlength from the left to the right hand but no ensuing after-effects. These findings failed to support the dynamic dominance model of bilateral transfer asymmetry, which posits the right hand is uniquely adapted for movement trajectory information. In the second experiment, participants adapted to the visuomotor rotation and generalized the adaptation to other workspaces. Subjects adapted to the visuomotor rotation in all three workspace locations. Corresponding neural measures indicated workspace related changes, with the biggest differences between contralateral and ipsilateral workspaces consistent with the observed behavioral results. The observed neurophysiological patterns were mainly in the right central and parietal– cortical areas involved in spatial processing. We argue these brain areas may be involved in workspace-related inhibition to allow the left hemisphere work efficiently. In the final experiment we investigated how manipulation of visual feedback and workspace location affected visuomotor adaptation for groups using real and remembered targets during performance. We showed participants visuomotor rotation transferred from the central to the ipsilateral workspace location. Also removing the target during rotational adaptation decreased, thus improved reaction time for unrotated real target trials regardless of workspace. Since gaze strategies differed between groups, we reasoned that gaze does not significantly contribute to visuomotor adaptation. The current studies add to existing evidence for understanding mechanisms responsible for adapting to a visuomotor rotation under different contexts