30 October 2019 Department of Computer Science , Alum , Research , Media

30 October 2019 – Computer Science PhD alumnus Dr Abdelhak Bentaleb was conferred the 2019 SIGMM Award for Outstanding PhD Thesis in Multimedia Computing. The award was presented at the 2019 ACM Multimedia conference held from 21 to 25 October in Nice, France.

The SIGMM Outstanding PhD Thesis award is presented annually to a researcher whose doctoral thesis has the potential for very high impact in multimedia computing, communication and applications. This is Abdelhak’s second award for his PhD thesis on multimedia streaming over computer networks. He won the DASH-IF Best PhD Dissertation Award at the ACM International Conference on Multimedia Systems (ACM MMSys) conference held in June this year.

Abdelhak graduated with a PhD in Computer Science on 30 June this year. While pursuing his PhD under the supervision of Associate Professor Roger Zimmermann, Abdelhak designed and developed a suite of solutions to optimise video quality in HTTP adaptive streaming. “Video streaming traffic on the Internet has grown dramatically in recent years,” explained Abdelhak. “This has posed a challenge for service providers as users demand for high quality video content without stalls while network infrastructure still suffer from sudden and high fluctuating bandwidth.”

To meet this growing need, a new video delivery system called Dynamic Adaptive Streaming over HTTP (DASH) was designed to deliver videos in a more efficient way. The system reduces the amount of time needed for videos to buffer by constantly altering the video’s quality as the user’s internet conditions change. To do so, videos are cut into shorter segments, with each segment encoded at a different bitrate level and resolution.

However, in a shared network environment with multiple DASH players competing for the common bandwidth, problems arise when each DASH player demand for the best quality possible without taking into account the needs of the other players. As a result, these video players suffer from video quality instability, quality unfairness and network resource underutilisation or oversubscription.

In his dissertation, Abdelhak developed seven novel solutions to manage network bandwidth allocation and provide a satisfactory viewing experience for multiple DASH players on the same network. While there are existing solutions designed to improve video quality, most of these solutions available are designed for specific environments and fail to perform well in a real world setting. “One of my goals in my research is to strike the right balance between academic research and commercial viability,” said Abdelhak. “And so the solutions I proposed are fully in compliance with industry standards and that they can be implemented into existing network infrastructure with minimal cost.”

“This win would not have been possible without the incredible support of my supervisors – Associate Professor Roger Zimmermann and Özyeğin University Assistant Professor Ali Begen. Without their inspiration and advice, my thesis would not have been completed. I would like to also thanks Associate Professor Ooi Wei Tsang, Klagenfurt University Associate Professor Christian Timmerer and UAE University Associate Professor Saad Harous for their valuable feedback and discussions,” said Abdelhak.

 

PhD Thesis:
Enabling Optimisations of Video Delivery in HTTP Adaptive Streaming