Nikolaos Papaoulakis

Personalized Coverage of Large Athletic Events

This article presents a platform that lets users direct their own coverage of large athletic events, letting them set up their own virtual director and orchestrate event viewing according to their preferences.

A Proactive, Terminal Based Best Access Point Selection Mechanism for Wireless LANs

In IEEE802.11 WLAN networks, Radio Resource Management (RRM) is necessary for the efficient use of scarce radio resources and to balance the telecommunication traffic load, among all the Access Points (APs) of the infrastructure network. In these networks, the mobile station MS has the functionality to select an AP, based on specific criteria. A key challenge is how to achieve overall load balancing in the network, during the AP reselection procedure in a way that will achieve the optimum utilization of network resources. The conventional approaches typically use the strongest received signal from the side of MS (RX Level) as the criterion, without considering the traffic load of each AP. In this work, we present two easy to implement WLAN resource management mechanisms that are fully compatible with the existing standards and mechanisms already supported by IEEE802.11 networks.

Real-time video analysis and personalized media streaming environments for large scale athletic events

This paper presents the architecture of the My-e-Director 2012, an FP7 call-1 European funded project in the objective area of Networked Media. My-e-Director 2012 is a unique interactive broadcasting platform, which enables end-users to have access on innovative services, like selection of focal actors/scenes and points of interest within real-time broadcasted streams. Emphasis is placed on the ambient camera selection module, which is the heart of the My-e-Director project. The ambient camera selection is responsible for detecting athletes in large-scale Olympic events. Then, this information is fed back to the system in order to allow for personalized video steaming and delivery services. Since detection of human in athletic event is a very demanding task, our method is based on a retrainable neural network architecture, which non-linearly models the color and texture properties of the object of interest. The retraining algorithm adapts the neural network model to fit the current environmental conditions, while simultaneously trusts as much as possible the previous information. The neural network classifier is combined with a conventional motion-based tracking scheme, which provides accurate contour detection. Aspects of multiple camera configurations are discussed.

Authentication platform for seamless handover in heterogeneous environments

This work tackles the hot issue of user handover from one network to another, or generally from one radio access technology (RAT) to another, in a 4G heterogeneous mobile and wireless environment without the interruption of an ongoing service (seamless handover) with user authentication support. This paper proposes an authenticated seamless handover mechanism and describes the authentication platform for two network environments: an operator with both GPRS and WLAN networks (the user performs a vertical handover). Two different WLAN operators (the user performs a horizontal handover)

SARACEN: A platform for adaptive, socially aware multimedia distribution over P2P networks

This paper presents the design of a platform for distribution of multimedia content streams supported through innovative techniques, both in terms of media encoding and media distribution. The platform architecture accommodates the use of scalable media coding techniques, including both standard and state of the art research methods (wavelets, multiple description coding), combined with new transport and realtime streaming protocols deployed over peer-to-peer networks. Furthermore, discovery of media resources and selection of peer nodes takes into account social networking related information, as this is available in user communities over the Internet. The design of the platform is taking place in the context of the European FP7 project SARACEN.

Handling multiple channel video data for personalized multimedia services: A case study on soccer games viewing

Personalization is undoubtedly present in todays pervasive and ubiquitous environments and tends to be an increasingly popular requirement in every technological aspect of the everyday life. When it comes to live multimedia services, however, there is still a lot to be done to satisfy the demanding user who wishes to view the most important parts of events that take place in parallel. In this paper, a service that allows users to personalize the provision of multimedia streaming services offered through broadcasting networks is described. The service is aimed at offering full personalization capabilities over traditionally broadcast oriented terminals such as TV sets and Set Top Boxes. Complete personalization can be achieved through analog TV or DVB broadcasts with the use of personal devices such as mobile phones by using IP connection for the return channel (RC) (DVBRC). A use case scenario featuring one example related to personalized viewing of two parallel athletic events (such as Champions League soccer matches) is described and used for the evaluation of a prototype implementation of the service.

A Network Oriented Perspective on the Personalization of Media Streaming

In this paper, the issue of real time personalized media streaming distribution over different networks is presented. Alternative scenarios are presented, together with details on implementation and discussion on the pros and cons, in terms of implementation complexity, traffic overhead and provided functionality. The solutions have been developed and are currently under evaluation in the context of My-e-Director 2012, an FP7 European funded project in the area of Networked Media. This project aims at providing an interactive, personalized broadcasting platform, which enables end-users to have access on innovative services and focusing on large scale athletic events.

Performance evaluation of GSM and GPRS systems based on measurement campaigns

A comprehensive study of the performance of GSM and GPRS is presented. The behavior of the network is classified into traffic load scenarios and key indicators are presented. Network response and logical channel occupation are discussed and the GPRS segment is evaluated according to a measurement campaign. Focus is given. on traffic overload and network congestion. This in-depth study can be used as a basis to evaluate the efficiency of resource management techniques in cellular systems.

Load balancing through terminal based dynamic AP reselection for QoS in IEEE 802.11 networks

In this paper, a mechanism for supporting Quality of Service in wireless networks through the dynamic reselection of Access Points (APs) according to a terminal based load balancing scheme is presented. The mechanism is analyzed, and a corresponding implementation on laptops is presented, while evaluation through both simulation and actual field trials are included. Implementation refers to both Linux and MS OS systems. For the evaluation of the mechanism in the field trials, a very demanding streaming video scenario is selected, and the results are assessed with respect to the improvements that can be introduced in the end user Quality of Experience, even over state of the art streaming adaptation solutions.

Emergency operations support through social networking and P2P multimedia services

In this paper we investigate the requirements and propose the design of a platform that will serve emergency operations such as in cases of wildfires or road accidents. This platform will provide assistance to the rescue and the disaster relief operations through the use of social networking and P2P based multimedia streaming. The general idea is to create a platform that will facilitate the provision of an efficient communication network between the stakeholders who will be involved in such life threatening situations and of the means for having a rich, multimedia based communication for first aid and guidance. Based on the use of the proposed platform the distribution of multimedia streams can be supported through innovative techniques such as media encoding and media distribution. The matching and notification of the most appropriate volunteers can be made through the use of personal profiles and the deployment of social networking tools. The access to multimedia content can be adapted to the obstacles which are introduced through the impairment of infrastructures of services capabilities.