International Congress on Information and Communication Technology

25-26 February 2021, London, UK

[PDF][Slides]

Nakisa Shams (ETS, Montreal, Canada), Hadi Amirpour (Alpen-Adria-Universität Klagenfurt), Christian Timmerer (Alpen-Adria-Universität Klagenfurt), and Mohammad Ghanbari (School of Computer Science and Electronic Engineering, University of Essex, Colchester, UK)

Abstract:

Keywords: Cognitive radio, Biological neural networks, Prediction, Idle channel.

At Christian Doppler laboratory ATHENA, we offer an internship*) for 2021 for Master Students and we kindly request your applications until 21st of December 2020 with the following data (in German or English):

• CV
• Record of study/transcript (“Studienerfolgsnachweis”)

*) A 3-month period in 2021 (with an exact time slot to be discussed) with the possibility to spend up to 1-month at the industrial partner; 20h per week “Universitäts-KV, Verwendungsgruppe C1, studentische Hilfskraft”

Please send your application by email to nina.stiller@aau.at.

About ATHENA: The Christian Doppler laboratory ATHENA (AdapTive Streaming over HTTP and Emerging Networked MultimediA Services) is jointly proposed by the Institute of Information Technology (ITEC; http://itec.aau.at) at Alpen-Adria-Universität Klagenfurt (AAU) and Bitmovin GmbH (https://bitmovin.com) to address current and future research and deployment challenges of HAS and emerging streaming methods. AAU (ITEC) has been working on adaptive video streaming for more than a decade, has a proven record of successful research projects and publications in the field, and has been actively contributing to MPEG standardization for many years, including MPEG-DASH; Bitmovin is a video streaming software company founded by ITEC researchers in 2013 and has developed highly successful, global R&D and sales activities and a world-wide customer base since then.

The aim of ATHENA is to research and develop novel paradigms, approaches, (prototype) tools, and evaluation results for the phases

1. multimedia content provisioning,
2. content delivery, and
3. content consumption in the media delivery chain as well as for
4. end-to-end aspects, with a focus on, but not being limited to, HTTP Adaptive Streaming (HAS).

The new approaches and insights are to enable Bitmovin to build innovative applications and services to account for the steadily increasing and changing multimedia traffic on the Internet.

Further details and registration available here: https://mile-high.video/

HTTP Adaptive Streaming – Where Is It Heading?

WebMedia2020, November 30 to December 4, 2020, Online

[PDF][Slides]

Abstract: Video traffic on the Internet is constantly growing; networked multimedia applications consume the predominant share of the available Internet bandwidth. A major technical breakthrough and enabler in multimedia systems research and of industrial networked multimedia services certainly was the HTTP Adaptive Streaming (HAS) technique. This resulted in the standardization of MPEG Dynamic Adaptive Streaming over HTTP (MPEG-DASH) which, together with HTTP Live Streaming (HLS) by Apple Inc., is widely used for multimedia delivery in today’s networks.
Existing challenges in multimedia systems research deal with the trade-off between (i) the ever-increasing content complexity, (ii) various requirements with respect to time (most importantly, latency), and (iii) quality of experience (QoE). Optimizing towards one aspect usually negatively impacts at least one of the other two aspects if not both.

This situation sets the stage for our research work in the ATHENA Christian Doppler (CD) Laboratory (Adaptive Streaming over HTTP and Emerging Networked Multimedia Services; https://athena.itec.aau.at/), jointly funded by public sources and industry.

In this talk, we will present selected novel approaches and research results of the first year of the ATHENA CD Lab’s operation. We will highlight HAS-related research on (i) multimedia content provisioning (machine learning for video encoding); (ii) multimedia content delivery (support of edge processing and virtualized network functions for video networking); (iii) multimedia content consumption and end-to-end aspects (player-triggered segment retransmissions to improve video playout quality); and (iv) novel QoE investigations (adaptive point cloud streaming). We will also put the work into the context of international multimedia systems research.

Biography: Christian Timmerer received his M.Sc. (Dipl.-Ing.) In January 2003 and his Ph.D. (Dr.techn.) In June 2006 (for research on the adaptation of scalable multimedia content in streaming and constraint environments ) both from the Alpen-Adria-Universität (AAU) Klagenfurt. He is currently an Associate Professor at the Institute of Information Technology (ITEC) and is the director of the Christian Doppler (CD) Laboratory ATHENA (https://athena.itec.aau.at/). His research interests include immersive multimedia communication, streaming, adaptation, and Quality of Experience. He co-authored seven patents and more than 200 articles in this area. He was the general chair of WIAMIS 2008, QoMEX 2013, MMSys 2016, and PV 2018 and has participated in several EC-funded projects, notably DANAE, ENTHRONE, P2P-Next, ALICANTE, SocialSensor, COST IC1003 QUALINET, and ICoSOLE. He also participated in ISO / MPEG work for several years, notably in the area of ​​MPEG-21, MPEG-M, MPEG-V, and MPEG-DASH where he also served as standard editor. In 2013 he cofounded Bitmovin (http://www.bitmovin.com/) to provide professional services around MPEG-DASH where he holds the position of the Chief Innovation Officer (CIO) – Head of Research and Standardization.

The International MultiMedia Modeling Conference (MMM)

June 22-24, 2021, Prague, Czech Republic

[PDF][Slides][Video]

Hadi Amirpour (Alpen-Adria-Universität Klagenfurt), Ekrem Çetinkaya (Alpen-Adria-Universität Klagenfurt), Christian Timmerer (Alpen-Adria-Universität Klagenfurt), and Mohammad Ghanbari (School of Computer Science and Electronic Engineering, University of Essex, Colchester, UK)

Abstract: HTTP Adaptive Streaming (HAS) enables high-quality streaming of video content. In HAS, videos are divided into short intervals called segments, and each segment is encoded at various quality/bitrates to adapt to the available bandwidth. Multiple encodings of the same content impose high costs for video content providers. To reduce the time-complexity of encoding multiple representations, state-of-the-art methods typically encode the highest quality representation first and reuse the information gathered during its encoding to accelerate the encoding of the remaining representations. As encoding the highest quality representation requires the highest time-complexity compared to the lower quality representations, it would be a bottleneck in parallel encoding scenarios and the overall time-complexity will be limited to the time-complexity of the highest quality representation. In this paper and to address this problem, we consider all representations from the highest to the lowest quality representation as a potential, single reference to accelerate the encoding of the other, dependent representations. We formulate a set of encoding modes and assess their performance in terms of BD-Rate and time-complexity, using both VMAF and PSNR as objective metrics. Experimental results show that encoding a middle quality representation as a reference, can significantly reduce the maximum en-coding complexity and hence it is an efficient way of encoding multiple representations in parallel. Based on this fact, a fast multirate encoding method is proposed which utilizes depth and prediction mode of a middle quality representation to accelerate the encoding of the dependent representations.

Keywords: HEVC, Video Encoding, Multirate Encoding, DASH

Dynamic Segment Repackaging at the Edge for HTTP Adaptive Streaming

IEEE International Symposium on Multimedia (ISM)

2-4 December 2020, Naples, Italy

https://www.ieee-ism.org/

[PDF][Slides][Video]

Jesús Aguilar Armijo (Alpen-Adria-Universität Klagenfurt), Babak Taraghi (Alpen-Adria-Universität Klagenfurt), Christian Timmerer (Alpen-Adria-Universität Klagenfurt), and Hermann Hellwagner (Alpen-Adria-Universität Klagenfurt)

Abstract: Adaptive video streaming systems typically support different media delivery formats, e.g., MPEG-DASH and HLS, replicating the same content multiple times into the network. Such a diversified system results in inefficient use of storage, caching, and bandwidth resources. The Common Media Application Format (CMAF) emerges to simplify HTTP Adaptive Streaming (HAS), providing a single encoding and packaging
format of segmented media content and offering the opportunities of bandwidth savings, more cache hits and less storage needed. However, CMAF is not yet supported by most devices. To solve this issue, we present a solution where we maintain the main
advantages of CMAF while supporting heterogeneous devices using different media delivery formats. For that purpose, we propose to dynamically convert the content from CMAF to the desired media delivery format at an edge node. We study the bandwidth savings with our proposed approach using an analytical model and simulation, resulting in bandwidth savings of up to 20% with different media delivery format distributions.
We analyze the runtime impact of the required operations on the segmented content performed in two scenarios: the classic one, with four different media delivery formats, and the proposed scenario, using CMAF-only delivery through the network. We
compare both scenarios with different edge compute power assumptions. Finally, we perform experiments in a real video streaming testbed delivering MPEG-DASH using CMAF content to serve a DASH and an HLS client, performing the media conversion for the latter one.

Keywords: CMAF, Edge Computing, HTTP Adaptive Streaming (HAS)