Paper accepted: LALISA: Adaptive Bitrate Ladder Optimization in HTTP-based Adaptive Live Streaming

IEEE/IFIP Network Operations and Management Symposium (NOMS)

8-12 May 2023- Miami, FL – USA

Farzad Tashtarian (Alpen-Adria-Universität Klagenfurt, Austria), Abdelhak Bentaleb (Concordia University, Canada), Hadi Amirpour (Alpen-Adria-Universität Klagenfurt, Austria), Babak Taraghi (Alpen-Adria-Universität Klagenfurt, Austria), Christian Timmerer (Alpen-Adria-Universität Klagenfurt, Austria), Hermann Hellwagner (Alpen-Adria-Universität Klagenfurt, Austria), Roger Zimmermann (National University of Singapore, Singapore)

Video content in Live HTTP Adaptive Streaming (HAS) is typically encoded using a pre-defined, fixed set of bitrate-resolution pairs (termed Bitrate Ladder), allowing playback devices to adapt to changing network conditions using an adaptive bitrate (ABR) algorithm. However, using a fixed one-size-fits-all solution when faced with various content complexities, heterogeneous network conditions, viewer device resolutions and locations, does not result in an overall maximal viewer quality of experience (QoE). Here, we consider these factors and design LALISA, an efficient framework for dynamic bitrate ladder optimization in live HAS. LALISA dynamically changes a live video session’s bitrate ladder, allowing improvements in viewer QoE and savings in encoding, storage, and bandwidth costs. LALISA is independent of ABR algorithms and codecs, and is deployed along the path between viewers and the origin server. In particular, it leverages the latest developments in video analytics to collect statistics from video players, content delivery networks and video encoders, to perform bitrate adder tuning. We evaluate the performance of LALISA against existing solutions in various video streaming scenarios using a trace-driven testbed. Evaluation results demonstrate significant improvements in encoding computation (24.4%) and bandwidth (18.2%) costs with an acceptable QoE

After the Game Jam is before the Game Jam

From December 9 to December 11, the 6th Klagenfurt Winter Jam took place at the Alpen-Adria Universität Klagenfurt. More than 80 highly motivated game enthusiasts worked for 48 hours on 21 new games and presented their results on Sunday to the public. More jammers joined online to participate remotely. It was an excellent comeback from the time of quarantines and restrictions, and the game jammers appreciated the event to make new contacts, work together, and meet old friends in a chilled and creative environment. Check out our video.

Save the date for the next Game Jams!

2nd Hüttenjam, a special event with limited seats, 13 – 16 April 2023

10th Game Jam will be on the weekend of 2 – 4 June 2023

 

 

 

Video Game Cultures 2023 – Call for Papers Out Now

We are happy to announce that the Call for Papers for our conference Video Game Cultures 2023: Exploring New Horizons is online now.

Please see our website for more info and submission.

Hadi
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Special Session on “Optimal Media Delivery” at ICME’23

ICME`23 July, 2023, Brisbane, Australia

Organizers:

  • Hadi Amirpour, University of Klagenfurt

  • Angeliki Katsenou, Trinity College Dublin, IE and University of Bristol, UK

Abstracts

Video streaming in the context of HTTP Adaptive Streaming (HAS) is replacing legacy media platforms and its market share is growing rapidly due to its simplicity, reliability, and standard support (e.g., MPEG-DASH). It results in an increasing number of video content, where nowadays, video accounts for the vast majority of today’s internet traffic either in the form of user-generated content (UGC) or pristine cinematic content. For HAS, the video is usually encoded in multiple versions (i.e., representations) of different resolutions, bitrates, codecs, etc. and each representation is divided into chunks (i.e., segments) of equal length (e.g., 2-10 second) to enable dynamic, adaptive switching during streaming based on the user’s context conditions (e.g., network conditions, device characteristics, user preferences). Read more

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Paper accepted: Context-aware Community Evolution Prediction in Online Social Networks

Athors: Alexander Lercher, Nishant Saurabh, Radu Prodan

The 15th IEEE International Conference on Social Computing and Networking
http://www.swinflow.org/confs/2022/socialcom/

Abstract: Community evolution prediction enables business-driven social networks to detect customer groups modeled as communities based on similar interests by splitting them into temporal segments and utilizing ML classification to predict their structural changes. Unfortunately, existing methods overlook business contexts and focus on analyzing customer activities, raising privacy concerns. This paper proposes a novel method for community evolution prediction that applies a context-aware approach to identify future changes in community structures through three complementary features. Firstly, it models business events as transactions, splits them into explicit contexts, and detects contextualized communities for multiple time windows. Secondly, it %it performs feature engineering by uses novel structural metrics representing temporal features of contextualized communities. Thirdly, it uses extracted features to train ML classifiers and predict the community evolution in the same context and other dependent contexts. Experimental results on two real-world data sets reveal that traditional ML classifiers using the context-aware approach can predict community evolution with up to three times higher accuracy, precision, recall, and F1-score than other baseline classification methods (i.e., majority class, persistence).

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Graphmassivizer @ Austrian Science Blog Schrödingerskatze.at

A new online article about Graphmassivizer has been published in the Science blog; check it out HERE.

Felix Schniz presented at “Transformative Play Initiative 2022” conference in Sweden

On 20 October 2022 Felix gave the talk “Walk Like an Englishman? The Cultural Experience of Walking Simulators” as part of the Transformative Play Initiative 2022 conference at Uppsala University, Sweden.
The content of the presentation was accepted for an article in the International Journal of Role-Playing (IJRP).
Felix talk titled “A Walk in the Park? Designing a Very British Gaming Experience” which he will be given together with Christoph Kaindel has been accepted for the Future and Reality of Gaming (FROG) Conference 2022 at Danube University Krems.

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A Webbing Journey @ Vienna Comic Con 2022

On the first two days of October 2022, Sebastian Uitz and Michael Steinkellner presented their game “A Webbing Journey” at the Vienna Comic Con 2022 (VIECC 2022). The new demo level from Gamescom was incorporated into the existing demo and replaced the old first level. In addition, the art style was updated, and the new arachnophobia mode was added to help everyone enjoy our game, even those afraid of spiders. This event was the biggest Austrian event we attended yet, with over 35.000 visitors. Next to meeting some cool Austrian game devs and having many happy players, we also had an interview with the FM4 Spielekammerl about our game.

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A Webbing Journey @ Gamescom 2022

From Wednesday, 24.08.2022, until Sunday, 28.08.2022, players from all over the world played our game “A Webbing Journey” at Gamescom 2022 in Cologne. Our booth was run by Sebastian Uitz, Manuel Santner, and Fabian Schober, and we have been one of the only two Austrian games in the indie area this year. The second one is Gibbon from Broken Rules. The size of the Gamescom is just crazy compared to the Austrian events, with over 250.000 people attending this year. We prepared a new demo level for this event, and the feedback was great, as always. In addition, we made valuable connections to the games industry through other game devs, publishers, and the press.

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futurezone Award 2022: ITEC was nominated for 2 projects

The futurezone Awards 2022 are looking for the most innovative ideas and projects. Three finalists (each category) have now been selected from the numerous submissions.

ITEC was nominated for two projects: 5G Virtual Realities and GAIA (together with Bitmovin).