MediaSync: Handbook on Multimedia Synchronization

This book provides an approachable overview of the most recent advances in the fascinating field of media synchronization (mediasync), gathering contributions from the most representative and influential experts. Understanding the challenges of this field in the current multi-sensory, multi-device, and multi-protocol world is not an easy task. The book revisits the foundations of mediasync, including theoretical frameworks and models, highlights ongoing research efforts, like hybrid broadband broadcast (HBB) delivery and users' perception modeling (i.e., Quality of Experience or QoE), and paves the way for the future (e.g., towards the deployment of multi-sensory and ultra-realistic experiences). Although many advances around mediasync have been devised and deployed, this area of research is getting renewed attention to overcome remaining challenges in the next-generation (heterogeneous and ubiquitous) media ecosystem. Given the significant advances in this research area, its current relevance and the multiple disciplines it involves, the availability of a reference book on mediasync becomes necessary. This book fills the gap in this context. In particular, it addresses key aspects and reviews the most relevant contributions within the mediasync research space, from different perspectives. Mediasync: Handbook on Multimedia Synchronization is the perfect companion for scholars and practitioners that want to acquire strong knowledge about this research area, and also approach the challenges behind ensuring the best mediated experiences, by providing the adequate synchronization between the media elements that constitute these experiences

A tutorial for olfaction-based multisensorial media application design and evaluation

© ACM, 2017. This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version was published in PUBLICATION, {VOL50, ISS5, September 2017} https://doi.org/10.1145/310824

An investigation into the use of intuitive control interfaces and distributed processing for enhanced three dimensional sound localization

This thesis investigates the feasibility of using gestures as a means of control for localizing three dimesional (3D) sound sources in a distributed immersive audio system. A prototype system was implemented and tested which uses state of the art technology to achieve the stated goals. A Windows Kinect is used for gesture recognition which translates human gestures into control messages by the prototype system, which in turn performs actions based on the recognized gestures. The term distributed in the context of this system refers to the audio processing capacity. The prototype system partitions and allocates the processing load between a number of endpoints. The reallocated processing load consists of the mixing of audio samples according to a specification. The endpoints used in this research are XMOS AVB endpoints. The firmware on these endpoints were modified to include the audio mixing capability which was controlled by a state of the art audio distribution networking standard, Ethernet AVB. The hardware used for the implementation of the prototype system is relatively cost efficient in comparison to professional audio hardware, and is also commercially available for end users. The successful implementation and results from user testing of the prototype system demonstrates how it is a feasible option for recording the localization of a sound source. The ability to partition the processing provides a modular approach to building immersive sound systems. This removes the constraint of a centralized mixing console with a predetermined speaker configuration

Error resilience and concealment techniques for high-efficiency video coding

This thesis investigates the problem of robust coding and error concealment in High Efficiency Video Coding (HEVC). After a review of the current state of the art, a simulation study about error robustness, revealed that the HEVC has weak protection against network losses with significant impact on video quality degradation. Based on this evidence, the first contribution of this work is a new method to reduce the temporal dependencies between motion vectors, by improving the decoded video quality without compromising the compression efficiency. The second contribution of this thesis is a two-stage approach for reducing the mismatch of temporal predictions in case of video streams received with errors or lost data. At the encoding stage, the reference pictures are dynamically distributed based on a constrained Lagrangian rate-distortion optimization to reduce the number of predictions from a single reference. At the streaming stage, a prioritization algorithm, based on spatial dependencies, selects a reduced set of motion vectors to be transmitted, as side information, to reduce mismatched motion predictions at the decoder. The problem of error concealment-aware video coding is also investigated to enhance the overall error robustness. A new approach based on scalable coding and optimally error concealment selection is proposed, where the optimal error concealment modes are found by simulating transmission losses, followed by a saliency-weighted optimisation. Moreover, recovery residual information is encoded using a rate-controlled enhancement layer. Both are transmitted to the decoder to be used in case of data loss. Finally, an adaptive error resilience scheme is proposed to dynamically predict the video stream that achieves the highest decoded quality for a particular loss case. A neural network selects among the various video streams, encoded with different levels of compression efficiency and error protection, based on information from the video signal, the coded stream and the transmission network. Overall, the new robust video coding methods investigated in this thesis yield consistent quality gains in comparison with other existing methods and also the ones implemented in the HEVC reference software. Furthermore, the trade-off between coding efficiency and error robustness is also better in the proposed methods

Virtual Reality Games for Motor Rehabilitation

This paper presents a fuzzy logic based method to track user satisfaction without the need for devices to monitor users physiological conditions. User satisfaction is the key to any product’s acceptance; computer applications and video games provide a unique opportunity to provide a tailored environment for each user to better suit their needs. We have implemented a non-adaptive fuzzy logic model of emotion, based on the emotional component of the Fuzzy Logic Adaptive Model of Emotion (FLAME) proposed by El-Nasr, to estimate player emotion in UnrealTournament 2004. In this paper we describe the implementation of this system and present the results of one of several play tests. Our research contradicts the current literature that suggests physiological measurements are needed. We show that it is possible to use a software only method to estimate user emotion

On the influence of individual characteristics and personality traits on the user experience with multi-sensorial media: an experimental insight

Recent studies encourage the development of sensorially-enriched media to enhance the user experience by stimulating senses other than sight and hearing. Sensory effects as odor, wind, vibration and light effects, as well as an enhanced audio quality, have been found to favour media enjoyment and to have a positive influence on the sense of Presence and on the perceived quality, relevance and reality of a multimedia experience. In particular, sports is among the genres that could benefit the most from these solutions. Several works have demonstrated also the technical feasibility of implementing and deploying end-to-end solutions integrating sensory effects into a legacy system. Thus, multi-sensorial media emerges as a mean to deliver a new form of immersive experiences to the mass market in a non-disruptive manner. However, many questions remain concerning issues as the sensory effects that can better complement a given audiovisual content or the best way in which to integrate and combine them to enhance the user experience of a target audience segment. The work presented in this paper aims to gain insight into the impact of binaural audio and sensory (light and olfactory) effects on the sports media experience, both at the overall level (average effect) and as a function of users? characteristics (heterogeneous effects). To this aim, we conducted an experimental study exploring the influence of these immersive elements on the quality and Presence dimensions of the media experience. Along the quality dimension, we look for possible variations on the quality scores assigned to the overall media experience and to the media components content, image, audio and sensory effects. The potential impact on Presence is analyzed in terms of Spatial Presence and Engagement. The users? characteristics considered encompass specific personal affective, cognitive and behavioral attributes. We found that, on average, participants preferred binaural audio than standard stereo audio. The audio quality was found to have a heterogeneous impact on the quality of experience, on the perceived quality of content and image and on the levels of Spatial Presence and Engagement. Furthermore, the presence of sensory effects increased significantly the level of Spatial Presence. Additionally, highly conscious participants reported a significantly higher image quality when sensory effects were present in comparison to those conditions in which sensory effects were not administered. Personal characteristics explained most of the variation in the dependent variables, being individuals? preferences in relation to the content, knowledge of involved technologies, tendency to emotional involvement and conscientiousness among the user variables with the most generalized influence

Semantics-aware content delivery framework for 3D Tele-immersion

3D Tele-immersion (3DTI) technology allows full-body, multimodal interaction among geographically dispersed users, which opens a variety of possibilities in cyber collaborative applications such as art performance, exergaming, and physical rehabilitation. However, with its great potential, the resource and quality demands of 3DTI rise inevitably, especially when some advanced applications target resource-limited computing environments with stringent scalability demands. Under these circumstances, the tradeoffs between 1) resource requirements, 2) content complexity, and 3) user satisfaction in delivery of 3DTI services are magnified. In this dissertation, we argue that these tradeoffs of 3DTI systems are actually avoidable when the underlying delivery framework of 3DTI takes the semantic information into consideration. We introduce the concept of semantic information into 3DTI, which encompasses information about the three factors: environment, activity, and user role in 3DTI applications. With semantic information, 3DTI systems are able to 1) identify the characteristics of its computing environment to allocate computing power and bandwidth to delivery of prioritized contents, 2) pinpoint and discard the dispensable content in activity capturing according to properties of target application, and 3) differentiate contents by their contributions on fulfilling the objectives and expectation of user’s role in the application so that the adaptation module can allocate resource budget accordingly. With these capabilities we can change the tradeoffs into synergy between resource requirements, content complexity, and user satisfaction. We implement semantics-aware 3DTI systems to verify the performance gain on the three phases in 3DTI systems’ delivery chain: capturing phase, dissemination phase, and receiving phase. By introducing semantics information to distinct 3DTI systems, the efficiency improvements brought by our semantics-aware content delivery framework are validated under different application requirements, different scalability bottlenecks, and different user and application models. To sum up, in this dissertation we aim to change the tradeoff between requirements, complexity, and satisfaction in 3DTI services by exploiting the semantic information about the computing environment, the activity, and the user role upon the underlying delivery systems of 3DTI. The devised mechanisms will enhance the efficiency of 3DTI systems targeting on serving different purposes and 3DTI applications with different computation and scalability requirements

AXMEDIS 2007 Conference Proceedings

The AXMEDIS International Conference series has been established since 2005 and is focused on the research, developments and applications in the cross-media domain, exploring innovative technologies to meet the challenges of the sector. AXMEDIS2007 deals with all subjects and topics related to cross-media and digital-media content production, processing, management, standards, representation, sharing, interoperability, protection and rights management. It addresses the latest developments and future trends of the technologies and their applications, their impact and exploitation within academic, business and industrial communities