Title: High Complexity and Bad Quality? Efficiency Assessment for Video QoE Prediction Approaches

Authors: Frank Loh, Gülnaziye Bingöl, Reza Farahani, Andrea Pimpinella, Radu Prodan, Luigi Atzori, Tobias Hoßfeld

Venue: 20th International Conference on Network and Service Management (CNSM 2024)

Abstract:  In recent years, video streaming has dominated Internet data traffic, prompting network providers to ensure high-quality streaming experiences to prevent customer churn. However, due to the encryption of streaming traffic, extensive network monitoring by providers is required to predict the streaming quality and improve their services. Several such prediction approaches have been studied in recent years, with a primary focus on the ability to determine key video quality degradation factors, often without considering the required resources or
energy consumption. To address this gap, we consider existing methods to predict key Quality of Experience (QoE) degradation factors from the literature and quantify the data that have to be monitored and processed for video streaming applications. Based on this, we assess the efficiency of different QoE degradation factor prediction approaches and quantify the ratio between efficiency and the achieved prediction quality. In this context, we identify significant disparities in the efficiency, influenced by data requirements and the specific prediction approach, and finally by the resulting quality. Consequently, we provide insights for network providers to choose the most appropriate method tailored to their specific requirements.

CERCIRAS (CA19135), short for Connecting Education and Research Communities for an Innovative Resource Aware Society is a 4-year long COST Action, started at the end of September 2020 and now nearing completion. One of the highlights of CERCIRAS has been its yearly Training School, a week-long residential school designed for current and future PhD students with research interests falling within the thematic scope of the Action and open to other profiles, including industry professionals. While perturbed by unfortunate overlap with the outbreak of the COVID pandemic, CERCIRAS managed to execute three consecutive Training Schools successfully: mid-September 2022 in Split (HR); early September 2023 in Riga (LV); and late August 2024 in Klagenfurt (AT). All editions of the CERCIRAS Training School follow a common structure: 4 selected lecture topics, which alternate frontal lessons and assisted hands-on works; 25 to 35 participants from as many participating countries as possible, with rich diversity for provenance, seniority level, and research focus; a rich portfolio of social activities.

The Training School places a considerable burden on the local hosts, which includes securing comfortable and affordable accommodation for a large troop, providing a modern and spacious lecture hall for all lectures and labs, with refreshments for the two daily breaks and nearby canteens for lunch, and arranging exciting options for a whole-afternoon diversion.

Dragi Kimovski recently visited Mother Theresa University in Skopje as part of the OeAD 6G Continuum project, which focuses on developing middleware for Artificial Intelligence over 6G networks. This visit is the next step in the collaboration between the involved institutions. During the stay, the kick-off meeting for the 6G Continuum project took place, bringing together researchers from both institutions to discuss the project’s goals and clarify the the research activities in terms of supporting AI traning and inference in the Edge over 6G networks. In addition to the research focus, this visit also helped to strengthen the ongoing partnership between the institutions. They explored new opportunities for collaboration in teaching and research, including student and faculty exchanges through Erasmus and CEEPUS programs.

Between July and August 2024, the ATHENA Christian Doppler Laboratory hosted four interns working on the following topics:

  • Halime Lezi: Image and Video Compression Pipeline
  • Luka Kaiser: VidStream
  • Julius van Dillen: Enhancing Video Quality with Super-Resolution

At the conclusion of their internships, they presented their work and results, receiving official certificates from the university. This collaboration was mutually beneficial for both the researchers at ATHENA and the interns. Their learning process was enhanced by the dedicated guidance they received, which included personalized mentorship, hands-on training, and continuous support. This comprehensive supervision ensured that they not only developed practical skills but also gained a deeper understanding of the research methodologies and technologies used in the video streaming field. We extend our gratitude to all three interns for their genuine interest, productive efforts, and valuable feedback on the laboratory.

Halime Lezi: I had an awesome time during my four-week internship at ATHENA. My project was about image and video compression, and I learned a lot about how it works. I also got to use Python, which was both fun and challenging. The work environment at ATHENA was really supportive and interesting. My supervisor, Emanuele Artioli, was super helpful and always ready to answer my questions. He made sure I understood both the practical and theoretical parts of my work, which was really cool. It was also great to work with people from different countries. The team was friendly, and we got along well. The work-life balance was good, with a nice mix of work and relaxation. Overall, my time at ATHENA was very educational and enjoyable. The skills and knowledge I gained during this internship will be really useful for my future studies and career. I’m thankful for the opportunity and the support I received. I would highly recommend this internship to anyone looking for a rewarding and fulfilling experience. It’s a great place to learn, grow, and meet new people.

Luka Kaiser: I had an amazing four weeks at ATHENA. It was really nice meeting new colleagues and even making new friends. The project I worked on was exactly what interests me, and if I had any questions, my supervisor, Christian, was always there to help me out. So, thank you very much for that. Overall, this experience has been incredibly valuable, and I learned a lot and gained practical skills that I will definitely use in the future. My time here was both productive and enjoyable. I am grateful for the opportunity and would love to stay connected with everyone I’ve met. Thank you once again for everything.

Julius van Dillen: My four-week internship at ATHENA was incredible. I focused on improving image and video quality through Super-Resolution techniques. I had the opportunity to work with a variety of tools and technologies, including FFmpeg, Visual Studio Code, Python, several Super-Resolution architectures, and various video quality metrics. I was truly surprised by how much Super-Resolution enhances video and image quality. I really enjoyed working with these technologies and found the entire process fascinating. I am grateful to have had Daniele as my supervisor; his guidance and support made the experience both easier and more enjoyable. During my internship, I gained valuable insights into the research process and the fundamentals of Python programming.

Published in: From Multimedia Communication to the Future Internet: Essays Dedicated to the Retirement of Prof. Dr. Dr. h.c. Ralf Steinmetz

Authors: Amr Rizk (Leibniz Universität Hannover, Germany), Hermann Hellwagner (AAU, Austria), Christian Timmerer (AAU, Austria), and Michael Zink (University of Massachusetts Amherst, MA, USA)

Abstract: Adaptivity is a cornerstone concept in video streaming. Equipped with the concept of Transitions, we review in this paper adaptivity mechanisms known from classical video streaming scenarios. We specifically highlight how these mechanisms emerge in a specific context, such that their performance finally depends on the deployment conditions. Using multiple examples we highlight the strength of the concept of adaptivity at runtime for video streaming.

Authors: Mohammad Ghasempour (AAU, Austria), Hadi Amirpour (AAU, Austria), and Christian Timmerer (AAU, Austria)

Abstract: Video streaming has become an integral part of our digital lives, driving the need for efficient video delivery. With the growing demand for seamless video delivery, adaptive video streaming has emerged as a solution to support users with varying device capabilities and network conditions. Traditional adaptive streaming relies on a predetermined set of bitrate-resolution pairs, known as bitrate ladders, for encoding. However, this “one-size-fits-all” approach is suboptimal when dealing with diverse video content. Consequently, per-title encoding approaches dynamically select the bitrate ladder for each content. However, in an era when carbon dioxide emissions have become a paramount concern, it is crucial to consider energy consumption. Therefore, this paper addresses the pressing issue of increasing energy consumption in video streaming by introducing a novel approach, ESTR, which goes beyond traditional quality-centric resolution selection approaches. Instead, the ESTR considers both video quality and decoding energy consumption to construct an optimal bitrate ladder tailored to the unique characteristics of each video content. To accomplish this, ESTR encodes each video content using a range of spatial and temporal resolutions, each paired with specific bitrates. It then establishes a maximum acceptable quality drop threshold (τ), carefully selecting resolutions that not only preserve video quality above this threshold but also minimize decoding energy consumption. Our experimental results, at a fixed τ of 2 VMAF steps, demonstrate a 32.87% to 41.86% reduction in decoding energy demand for HEVC-encoded videos across various software decoder implementations and operating systems, with a maximum bitrate increase of 2.52%. Furthermore, on a hardware-accelerated client device, a 46.37% energy saving was achieved during video playback at the expense of a 2.52% bitrate increase. Remarkably, these gains in energy efficiency are achieved while maintaining consistent video quality.

From July 20-28, 2024, the 5th Edition of the Data Science International Summer School, managed by Bucharest Business School (BBS @ ASE) and in collaboration with  GATE Institute at Sofia University “St. Kliment Ohridski” and the projects enRichMyData , Graph-Massivizer , UPCAST , INTEND , and InterTwino took place in Predeal, Romania. Radu participated as a speaker and mentor and also presented the Graph-Massivizer project.

Prestigious Speakers:

Dan Nicolae (University of Chicago, USA), Razvan Bunescu (University of North Carolina at Charlotte, USA), Anna Fensel Wageningen University & Research, the Netherlands), Radu Prodan (University of Klagenfurt, Austria), Ioan Toma (Onlim GmbH, Austria), Dumitru Roman (SINTEF / University of Oslo, Norway), Jože Rožanec (Qlector, Slovenia), Daniel Thilo Schroeder (SINTEF, Norway), Gabriel Terejanu, PhD (University of North Carolina at Charlotte, USA), Hui Song (SINTEF, Norway), Viktor Sowinski-Mydlarz (London Metropolitan University, UK and GATE Institute, Bulgaria), Roberto Avogadro (SINTEF, Norway), Nikolay Nikolov (SINTEF AS, Norway).

The EU has approved the DATAPACT project (Datapact: Compliance by Design of Data/AI Operations and Pipelines) application.The project has a total volume of 9,9 Mio. Euros and 19 partners, including ITEC (Radu Prodan).

DataPACT will develop novel tools and methodologies that enable efficient, compliant, ethical, and sustainable data/AI operations and pipelines. DataPACT will deliver a transformative approach where compliance, ethics, and environmental sustainability are not afterthoughts but foundational elements of data/AI operations and pipelines.

 

The Christian Doppler (CD) Laboratory ATHENA was established in October 2019 to tackle current and future research and deployment challenges of HTTP Adaptive Streaming (HAS) and emerging streaming methods. The goal of CD laboratories is to conduct application-oriented basic research, promote collaboration between universities and companies, and facilitate technology transfer. They are funded through a public-private partnership between companies and the Christian Doppler Research Association, which is funded by the Ministry for Digital and Economic Affairs and the National Foundation for Research, Technology, and Development (Nationalstiftung für Forschung, Technologie und Entwicklung (FTE)). ATHENA is supported by Bitmovin as a company partner.

The CD laboratories have a duration of seven years and undergo rigorous scientific review after two and five years. This spring, the CD lab ATHENA completed its 5-year evaluation, and we have just received official notification from the CDG that we have successfully passed the review. Consequently, it is time to briefly outline the main achievements during this second phase (i.e., years 2 to 5) of the CD lab ATHENA.

Before exploring the achievements, it’s important to highlight the ongoing relevance of research in video streaming, given its dominance in today’s Internet usage. The January 2024 Sandvine Internet Phenomena report revealed that video streaming accounts for 68% of fixed/wired Internet traffic and 64% for mobile Internet traffic. Specifically, Video on Demand (VoD) represents 54% of fixed/wired and 57% of mobile traffic, while live streaming contributes to 14% of fixed/wired and 7% of mobile traffic. The major services in this domain include YouTube and Netflix, each commanding more than 10% of the overall Internet traffic, with TikTok, Amazon Prime, and Disney+ also playing significant roles.

ATHENA is structured into four work packages, each with distinct objectives as detailed below:

  1. Content provisioning: Primarily involves video encoding for HAS, quality-aware encoding, learning-based encoding, and multi-codec HAS.
  2. Content delivery: Addresses HAS issues by utilizing edge computing, exchanging information between CDN/SDN and clients, providing network assistance for clients, and evaluating corresponding utilities.
  3. Content consumption: Focuses on bitrate adaptation schemes, playback improvements, context and user awareness, and studies on Quality of Experience (QoE).
  4. End-to-end aspects: Offers a comprehensive view of application and transport layer enhancements, Quality of Experience (QoE) models, low-latency HAS, and learning-based HAS.

During the 2nd phase of ATHENA’s work, we achieved significant results, including publications in respected academic journals and conferences. Specifically, our publications were featured in key multimedia, signal processing, computer networks & wireless communication, and computing systems venues, as categorized by Google Scholar under engineering and computer science. Some of the notable publications include IEEE Communications Surveys & Tutorials (impact factor: 35.6), IEEE Transactions on Image Processing (10.6), IEEE Internet of Things Journal (10.6), IEEE Transactions on Circuits and Systems for Video Technology (8.4), and IEEE Transactions on Multimedia (7.3).

Furthermore, we focused on technology transfer by submitting 16 invention disclosures, resulting in 13 patent applications (including provisionals). Collaborating with our company partner, we obtained 6 granted patents. Additionally, we’re pleased to report on the progress of our spin-off projects, as well as the funding secured for two FFG-funded projects named APOLLO and GAIA, and an EU Horizon Europe-funded innovation action called SPIRIT.

The ATHENA team was also active in organizing scientific events such as workshops, special sessions, and special issues at IEEE ICME, ACM MM, ACM MMSys, ACM CoNEXT, IEEE ICIP, PCS, and IEEE Network. We also contributed to reproducibility in research through open source tools (e.g., Video Complexity Analyzer and LLL-CAdViSE) and datasets (e.g., Video Complexity Dataset and Multi-Codec Ultra High Definition 8K MPEG-DASH Dataset) among others.

We also note our contributions to the applications of AI in video coding & streaming, for example in video coding and video streaming as follows:

A major outcome of the second phase is the successful defense of the inaugural cohort of PhD students:

Two postdoctoral scholars have reached a significant milestone on their path toward habilitation

During the second phase, each work package produced excellent publications in their domain, briefly highlighted in the following. Content provisioning (WP-1) focuses mainly on video coding for HAS (43 papers) and immersive media coding for streaming (4 papers). The former can be further subdivided into the following topic areas:

  • Video complexity: spatial and temporal feature extraction (4 papers)
  • Compression efficiency improvement of individual representations (1 paper)
  • Encoding parameter prediction for HAS (9 papers)
  • Efficient bitrate ladder construction (4 papers)
  • Fast multi-rate encoding (3 papers)
  • Data security and data hiding (7 papers)
  • Energy-efficient video encoding for HAS (4 papers)
  • Advancing video quality evaluation (7 papers)
  • Datasets (4 papers)

Content delivery (WP-2) dealt with SDN/CDN assistance for HAS, edge computing support for HAS, and network-embedded media streaming support, resulting in 21 papers. Content consumption (WP-3) worked on QoE enhancement mechanisms at client-side and QoE- and energy-aware content consumption (11 papers). Finally, end-to-end Aspects (WP-4) produced 15 papers in the area of end-to-end QoE improvement in multimedia video streaming. We reported 94 papers published/accepted for the ATHENA 5-year evaluation.

In this context, it is also important to highlight the collaboration within ATHENA, which has resulted in joint publications across various work packages (WPs) and with other ITEC members. For example, collaborations with Prof. Schöffmann (FWF-funded project OVID), FFG-funded projects APOLLO/GAIA, and EU-funded project SPIRIT. In addition, we would like to acknowledge our international collaborators, such as Prof. Hongjie He from Southwest Jiaotong University, Prof. Patrick Le Callet from the University of Nantes, Prof. Wassim Hamidouche from the Technology Innovation Institute (UAE), Dr. Sergey Gorinsky from IMDEA, Dr. Abdelhak Bentaleb from Concordia University, Dr. Raimund Schatz from AIT, and Prof. Pablo Cesar from CWI. We are also pleased to report the successful technology transfers to Bitmovin, particularly CAdViSE (WP-4) and WISH ABR (WP-3). Regular “Fun with ATHENA” meetups and Break-out Groups are utilized for in-depth discussions about innovations and potential technology transfers.

Over the next two years, the ATHENA project will prioritize the development of deep neural network/AI-based image and video coding within the context of HAS. This includes energy- and cost-aware video coding for HAS, immersive video coding such as volumetric video and holography, as well as Quality of Experience (QoE) and energy-aware content consumption for HAS (including energy-efficient, AI-based live video streaming) and generative AI for HAS.

Thanks to all current and former ATHENA team members: Samira Afzal, Hadi Amirpour, Jesús Aguilar Armijo, Emanuele Artioli, Christian Bauer, Alexis Boniface, Ekrem Çetinkaya, Reza Ebrahimi, Alireza Erfanian, Reza Farahani, Mohammad Ghanbari (late), Milad Ghanbari, Mohammad Ghasempour, Selina Zoë Haack, Hermann Hellwagner, Manuel Hoi, Andreas Kogler, Gregor Lammer, Armin Lachini, David Langmeier, Sandro Linder, Daniele Lorenzi, Vignesh V Menon, Minh Nguyen, Engin Orhan, Lingfeng Qu, Jameson Steiner, Nina Stiller, Babak Taraghi, Farzad Tashtarian, Yuan Yuan, and Yiying Wei. Finally, thanks to ITEC support staff Martina Steinbacher, Nina Stiller, Margit Letter, Marion Taschwer, and Rudolf Messner.

We also would like to thank the Christian Doppler Research Association for continuous support, organizing the review, and the reviewer for constructive feedback!

On Friday, July 5 2024, Tom Tuček and Felix Schniz visited the Kwadrat youth centre in Klagenfurt for a workshop on computer role-playing games. Together with a group of highly motivated youngsters (and Kwadrat staff members!), they analysed the opening sequence of the best-selling game Baldur’s Gate 3 together. Afterwards, they introduced the audience to the pen-and-paper roots of modern role-playing games and invited everybody tomjoin a session of the classic Dungeons and Dragons, wonderfully hosted by Tom.

The workshop was well visited and received. Further events to introduce the Klagenfurt youth to the wonders of computer game design are already in the planning.