SDART: Spatial Dart AR Simulation with Hand-Tracked Input

ACM Multimedia 2025

October 27 – October 31, 2025

Dublin, Ireland

[PDF]

Milad Ghanbari (AAU, Austria), Wei Zhou (Cardiff, UK), Cosmin Stejerean (Meta, US), Christian Timmerer (AAU, Austria), Hadi Amirpour (AAU, Austria)

Abstract: We present a physics-driven 3D dart-throwing interaction system for Apple Vision Pro (AVP), developed using Unity 6 engine and running in augmented reality (AR) mode on the device. The system utilizes the PolySpatial and Apple’s ARKit software development kits (SDKs) to ensure hand input and tracking in order to intuitively spawn, grab, and throw virtual darts similar to real darts. The application benefits from physics simulations alongside the innovative no-controller input system of AVP to manipulate objects realistically in an unbounded spatial volume. By implementing spatial distance measurement, scoring logic, and recording user performance, this project enables user studies on quality of experience in interactive experiences. To evaluate the perceived quality and realism of the interaction, we conducted a subjective study with 10 participants using a structured questionnaire. The study measured various aspects of the user experience, including visual and spatial realism, control fidelity, depth perception, immersiveness, and enjoyment. Results indicate high mean opinion scores (MOS) across key dimensions. Link to video: Link

Hadi

VQualA 2025 Challenge on Image Super-Resolution Generated Content Quality Assessment: Methods and Results

ICCV VQualA 2025

October 19 – October 23, 2025

Hawai’i, USA

[PDF]

Hadi Amirpour (AAU, Austria), et al.

Abstract: This paper presents the ISRGC-Q Challenge, built upon the Image Super-Resolution Generated Content Quality Assessment (ISRGen-QA) dataset, and organized as part of the Visual Quality Assessment (VQualA) Competition at the ICCV 2025 Workshops. Unlike existing Super-Resolution Image Quality Assessment (SR-IQA) datasets, ISRGen-QA places greater emphasis on SR images generated by the latest generative approaches, including Generative Adversarial Networks (GANs) and diffusion models. The primary goal of this challenge is to analyze the unique artifacts introduced by modern super-resolution techniques and to evaluate their perceptual quality effectively. A total of 108 participants registered for the challenge, with 4 teams submitting valid solutions and fact sheets for the final testing phase. These submissions demonstrated state-of-the-art (SOTA) performance on the ISRGen-QA dataset. The project is publicly available at: https://github.com/Lighting-YXLI/ISRGen-QA.

VQualA 2025 Challenge on Face Image Quality Assessment: Methods and Results

ICCV VQualA 2025

October 19 – October 23, 2025

Hawai’i, USA

[PDF]

MohammadAli Hamidi (University of Cagliari, Italy), Hadi Amirpour (AAU, Austria), et al.

Abstract: Face images have become integral to various applications. but real-world capture conditions often lead to degradations such as noise, blur, compression artifacts, and poor lighting. These degradations negatively impact image quality and downstream tasks. To promote advancements in face image quality assessment (FIQA), we introduce the VQualA 2025 Challenge on Face Image Quality Assessment, part of ICCV 2025 Workshops. Participants developed efficient models (≤0.5 GFLOPs, ≤5M parameters) predicting Mean Opinion Scores (MOS) under realistic degradations. Submissions were rigorously evaluated using objective metrics and human perceptual judgments. The challenge attracted 127 participants, resulting in 1519 valid final submissions. Detailed methodologies and results are presented, contributing to practical FIQA solutions.

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A Lightweight Ensemble-Based Face Image Quality Assessment Method with Correlation-Aware Loss

ICCV VQualA 2025

October 19 – October 23, 2025

Hawai’i, USA

 

MohammadAli Hamidi (University of Cagliari, Italy), Hadi Amirpour (AAU, Austria), Luigi Atzori (University of Cagliari, Italy)Christian Timmerer (AAU, Austria),

Abstract:Face image quality assessment (FIQA) plays a critical role in face recognition and verification systems, especially in uncontrolled, real-world environments. Although several methods have been proposed, general-purpose no-reference image quality assessment techniques often fail to capture face-specific degradations. Meanwhile, state-of-the-art FIQA models tend to be computationally intensive, limiting their practical applicability. We propose a lightweight and efficient method for FIQA, designed for the perceptual evaluation of face images in the wild. Our approach integrates an ensemble of two compact convolutional neural networks, MobileNetV3-Small and ShuffleNetV2, with prediction-level fusion via simple averaging. To enhance alignment with human perceptual judgments, we employ a correlation-aware loss (MSECorrLoss), combining mean squared error (MSE) with a Pearson correlation regularizer. Our method achieves a strong balance between accuracy and computational cost, making it suitable for real-world deployment. Experiments on the VQualA FIQA benchmark demonstrate that our model achieves a Spearman rank correlation coefficient (SRCC) of 0.9829 and a Pearson linear correlation coefficient (PLCC) of 0.9894, remaining within competition efficiency constraints.

Hadi

Depth-Enabled Inspection of Medical Videos

ACM Multimedia 2025

October 27 – October 31, 2025

Dublin, Ireland

Hadi Amirpour (AAU, Austria), Doris Putzgruber-Adamitsch (AAU, Austria), Yosuf El-Shabrawi (Kabeg, Austria), Klaus Schoeffmann (AAU, Austria)

Abstract: Cataract surgery is the most frequently performed surgical procedure worldwide, involving the replacement of a patient’s clouded eye lens with a synthetic intraocular lens to restore visual acuity. Although typically brief, the operation consists of distinct phases that demand precision and extensive training, traditionally constrained by the limitations of real-time observation under a microscope. To enhance learning and procedural accuracy, modern advancements in stereoscopic video capture and head-mounted displays (HMDs) offer a promising solution. This paper demonstrates the application of stereoscopic cataract surgery videos, visualized through Apple Vision Pro (AVP) and Meta Quest 3, to provide immersive 3D perspectives that enhance depth perception and spatial awareness. An expert evaluation study with experienced surgeons indicates that stereoscopic visualization significantly improves comprehension of spatial relationships and procedural maneuvers, suggesting its potential to revolutionize surgical education and real-time guidance in ophthalmic surgery. Demo video: Link

A Tutorial at  ACM SIGCOMM 2025

Optimizing Low-Latency Video Streaming: AI-Assisted Codec-Network Coordination

[Link]

Coimbra, Portugal, September 8 – 11, 2025.


Tutorial speakers:

  • Farzad Tashtarian (Alpen-Adria-Universität – AAU)
  • Zili Meng (Hong Kong University of Science and Technology – HKUST)
  • Abdelhak Bentaleb (Concordia University)
  • Mahdi Dolati (Sharif University of Technology)

This tutorial focuses on the emerging need for ultra-low-latency video streaming and how AI-assisted coordination between codecs and network infrastructure can significantly improve performance. Traditional end-to-end streaming pipelines are often disjointed, leading to inefficiencies under tight latency constraints. We present a cross-layer approach that leverages AI for real-time encoding parameter adaptation, network-aware bitrate selection, and joint optimization across codec behavior and transport protocols. The tutorial examines the integration of AI models with programmable network architectures (e.g., SDN, P4) and modern transport technologies such as QUIC and Media over QUIC (MoQ) to minimize startup delay, stall events, and encoding overhead. Practical use cases and experimental insights illustrate how aligning codec dynamics with real-time network conditions enhances both QoE and system efficiency. Designed for both researchers and engineers, this session provides a foundation for developing next-generation intelligent video delivery systems capable of sustaining low-latency performance in dynamic environments.

Conference Talk:

On 20 June 2025, Dr Felix Schniz held the talk “Plain Walking? Navigating Space in Trading Card Games” for the Card Game Conference at AAU, Klagenfurt (AT). The Card Game Conference was a mini conference organised by students of the master’s programme Game Studies and Engineering, intended as a low-barrier science to science and science to public event.

 

Workshop:

With „Plain Walking? The Workshop”, Dr Felix Schniz held a science-to-science workshop on 21 June 2025 as a follow-up to his presentation at the Card Game Conference.

 

Conference Accept:

With his talk “In Cardboard Space, No One Can Hear Your Scream: The Alien Universe Between Digital and Analogue Game Experiences”, Dr Felix Schniz has been accepted for the Video Game Cultures Conference 2025 at Charles University, Prague (CZ).

 

Paper Published:

Together with his colleagues Thomas Faller, Armin Lippitz, and René Reinhold Schallegger, Dr Felix Schniz has published the paper “Teaching (With) Canadian Videogames in the Classroom” in the anthology Teaching Canada II: Identities, Cultures, Regions.

 

 

 

Real-Time AI-Driven Avatar Generation for Sign Language in HTTP Adaptive Streaming

The 3rd ACM SIGCOMM Workshop on Emerging Multimedia Systems (ACM EMS 2025)

https://conferences.sigcomm.org/sigcomm/2025/workshop/ems/

8 September 2025 // Coimbra, Portugal

 

Daniele Lorenzi (AAU, Austria), Emanuele Artioli (AAU, Austria), Farzad Tashtarian (AAU, Austria), Christian Timmerer (AAU, Austria)

Abstract: As digital media consumption over the Internet surges globally, ensuring accessibility for all users becomes paramount. For people with hearing impairments, this means providing inclusion beyond classic captioning, which does not convey the full emotional and contextual depth of spoken content. This work addresses this accessibility gap by exploring the use of AI-generated avatars capable of translating speech into sign language in real-time. After defining the multifaceted challenges in this domain, we propose a novel AI-driven task partition to animate avatars for accurate and expressive sign language interpretations in live streaming.

Hadi

Unlocking Implicit Motion for Evaluating Image Complexity
Displays

 

Yixiao Lia (Beihang University, China), Xiaoyuan Yang (Beihang University, China), Yanda Meng (University of Exeter, UK), Hadi Amirpour (AAU, AT), Jiang Liu (Cardiff University, UK), Yuqing Luo (Cardiff University, UK), Hantao Liu (Cardiff University, UK), and Wei Zhou (Cardiff University, UK)

Abstract: Image complexity (IC) plays a critical role in both cognitive science and multimedia computing, influencing visual aesthetics, emotional responses, and tasks such as image classification and enhancement. However, defining and quantifying IC remains challenging due to its multifaceted nature, which encompasses both objective attributes (e.g., detail, structure) and subjective human perception. While traditional methods rely on entropy-based or multidimensional approaches, and recent advances employ machine learning and shallow neural networks, these techniques often fail to fully capture the subjective aspects of IC. Inspired by the fact that the human visual system inherently perceives implicit motion in static images, we propose a novel approach to address this gap by explicitly incorporating hidden motion into IC assessment. We introduce the motion-inspired image complexity assessment metric (MICM) as a new framework for this purpose. MICM introduces a dual-branch architecture: One branch extracts spatial features from static images, while the other generates short video sequences to analyze latent motion dynamics. To ensure meaningful motion representation, we design a hierarchical loss function that aligns video features with text prompts derived from image-to-text models, refining motion semantics at both local (i.e., frame and word) and global levels. Experiments on three public image complexity assessment (ICA) databases demonstrate that our approach, MICM, significantly outperforms state-of-the-art methods, validating its effectiveness. The code will be publicly available upon acceptance of the paper.

 

On Monday, 16 June 2025, Sabrina Größing, BEd and Dr Felix Schniz presented the Master’s Programme Game Studies and Engineering to an audience of bachelor students from the novel Liberal Arts programme.

 

The event aimed to showcase how easily they can continue their academic career within AAU, the opportunities and support structures awaiting them by doing so, and provide a gateway into studying at the university’s technical faculty.