DAg-stream: Distributed video adaptation for overlay streaming to heterogeneous devices

Combining the advantages of Peer-to-Peer (P2P) content distribution concept and metadata driven adaptation of videos in compressed domain, in this paper, we propose a simple but scalable design of distributed adaptation and overlay streaming using MPEG-21 gBSD, called DAg-stream. The objective is not only to shift the bandwidth burden to end participating peers, but also to move the computation load for adapting video contents away from dedicated media-streaming/adaptation servers. It is an initiative to merge the adaptation operations and the P2P streaming basics to support the expansion of context-aware mobile P2P systems. DAg-stream organizes mobile and heterogeneous peers into overlays. For each video, a separate overlay is formed. No control message is exchanged among peers for overlay maintenance. We present a combination of infrastructure-centric and application end-point architecture. The infrastructure-centric architecture refers to a tree controller, named DAg-master, which is responsible for tree/overlay administering and maintenance. The application end-point architecture refers to video sharing, streaming and adaptation by the participating resourceful peers. The motivation for this work is based on the experiences and lessons learned so far about developing a video adaptation system for heterogeneous devices. In this article, we present our architecture and some experimental evaluations supporting the design concept for overlay video streaming and online adaptation.

Shervin ShirmohammadiEmail:

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Razib Iqbal   is pursuing his Ph.D. degree in Computer Science at the University of Ottawa (uOttawa), Canada. His current research interests include — Distributed and online video adaptation, and video watermaking. Mr. Iqbal received his Masters and Bachelors degree, both in Computer Science, from uOttawa in 2006 and North South University, Bangladesh in 2003 respectively. He is a recipient of the uOttawa International Admission Scholarship for both his Masters and Ph.D. studies. Shervin Shirmohammadi   Associate Professor at the School of Information Technology and Engineering, University of Ottawa, Canada, joined the University as an Assistant Professor in 2004, after 4 years of industry experience as a Senior Software Architect and Project Manager that followed his Ph.D. degree in Electrical Engineering from the same University in 2000. His current research interests include Massively Multiuser Online Gaming (MMOG) and Virtual Environments, Application Layer Multicasting and Overlay Networks, Adaptive P2P Audio/Video Streaming, and Multimedia Assisted Rehabilitation Engineering. In addition to his academic publications, which include two Best Paper Awards, he has over a dozen technology transfers to the private sector. He is Editor-in-Chief of the International Journal of Advanced Media and Communications, Associate Editor of ACM Transactions on Multimedia Computing, Communications, and Applications, Associate Editor of Springer's Journal of Multimedia Tools and Applications, and also chairs or serves on the program committee of a number of conferences in multimedia, virtual environments and games, and medical applications. Dr. Shirmohammadi is a University of Ottawa Gold Medalist, a licensed Professional Engineer in Ontario, a Senior Member of the IEEE, and a Professional Member of the ACM.