At QoMEX 2024, a stereoscopic 360-degree hybrid conference experience was demonstrated. The camera itself was standing some few meters away from the test person, which meant that the latter could see her-/himself with a latency of one to two seconds. While ACR scores of overall, image quality, depth perception were positive and in line with each other, the latency-related DCR scores were more ambiguous. Corresponding statistics will be shown in this paper along with qualitative feedback from the test persons. The demonstration in 2025 takes the step to a more realistic use case where the stereoscopic 360-degree camera will be placed in Sweden, about 2200 km away from the QoMEX 2025 location in Madrid. Immediate quantitative and qualitative insights are expected to demonstrate the trade-off between image quality and delay perceptions that come with Trans-European Event Broadcasting (TEEB) over various networks.

This paper reflects on the role of Human-Computer Interaction (HCI) research and practice both in addressing and exacerbating current environmental crises. Observing a discrepancy between the urgency of these crises and the attention they receive in HCI, we generated and analysed twelve fictional narratives that speculate about what it could mean if HCI prioritized environmental sustainability. This exercise helped us identify possible strategies towards this aim through addressing HCI practices such as conferencing, teaching and research. These strategies include building on existing meso-level initiatives in the community, reorienting reviewing processes, practising prefiguration, being mindful of diverse perspectives, and adding a touch of humour. Publishing our set of narratives in the form of a book of fairy tales alongside this paper is one step in that direction. We hope the book and the paper contribute to raising and nuancing the topic of (un)sustainability in HCI. 

The integration of outdoor smartphone applications with fitness trackers has introduced new opportunities and challenges for user interaction, particularly in mobility-driven activities. While these innovations offer significant benefits, they also pose challenges due to the many factors influencing the user’s quality of experience. Traditional methods of assessing user experiences, such as offline surveys and static questionnaires, often fail to capture the dynamic nature of outdoor activities. This research proposes a novel Quality of Experience (QoE) methodology for mobile applications to enhance the assessment of user experiences in cycling. Focusing on a use case in Blekinge, Sweden, where residents were encouraged to adopt cycling for daily transportation, we extracted land cover data and developed a server-side workflow for bicycle path segmentation. By incorporating dynamic surveys that adapt to users’ real-time experiences, we aim to generate a more accurate and context-aware dataset. This study makes several key contributions: First, it presents a scalable method for bicycle path segmentation; second, it demonstrates the utility and benefits of land cover data extraction; and finally, it evaluates the effectiveness of QoE influence factors through user surveys based on real-world cyclist feedback. This approach is expected to enhance the planning and development of cycling infrastructure by providing urban planners and stakeholders with valuable user insights using adaptable surveys based on route segmentation.

Mobile gaming accounts for more than 50% of global online gaming revenue, surpassing console and browser-based gaming. The success of mobile gaming titles depends on optimizing applications for the specific hardware constraints of mobile devices, such as smaller displays and lower computational power, to maximize battery life. Additionally, these applications must dynamically adapt to the variations in network speed inherent in mobile environments. Ultimately, user engagement and satisfaction are critical, necessitating a favorable comparison to browser and console-based gaming experiences. While Quality of Experience (QoE) subjective evaluations through user surveys are the most reliable method for assessing user perception, various factors, termed influence factors (IFs), can affect user ratings of stimulus quality. This study examines human influence factors in mobile gaming, specifically analyzing the impact of user delight towards displayed content and the effect of gaze tracking. Using Pupil Core eye-tracking hardware, we captured user interactions with mobile devices and measured visual attention. Video stimuli from eight popular games were selected, with resolutions of 720p and 1080p and frame rates of 30 and 60 fps. Our results indicate a statistically significant impact of user delight on the MOS for most video stimuli across all games. Additionally, a trend favoring higher frame rates over screen resolution emerged in user ratings. These findings underscore the significance of optimizing mobile gaming experiences by incorporating models that estimate human influence factors to enhance user satisfaction and engagement.

While current video quality assessment research predominantly revolves around resolutions of 4 K and beyond, targeted at ultra high-definition (UHD) displays, effective video quality for mobile video streaming remains primarily within the range of 480 p to 1080 p. In this study, we conducted a comparative analysis of the quality of experience (QoE) for widely implemented video codecs on mobile devices, specifically Advanced Video Coding (AVC), its successor High-Efficiency Video Coding (HEVC), and Google’s VP9. Our choice of 720 p video sequences from a newly developed database, all with identical bitrates, aimed to maintain a manageable subjective assessment duration, capped at 35–40 min. To mimic real-time network conditions, we generated stimuli by streaming original video clips over a controlled emulated setup, subjecting them to eight different packet-loss scenarios. We evaluated the quality and structural similarity of the distorted video clips using objective metrics, including the Video Quality Metric (VQM), Peak Signal-to-Noise Ratio (PSNR), Video Multi-Method Assessment Fusion (VMAF), and Multi-Scale Structural Similarity Index (MS-SSIM). Subsequently, we collected subjective ratings through a custom mobile application developed for Android devices. Our findings revealed that VMAF accurately represented the degradation in video quality compared to other metrics. Moreover, in most cases, HEVC exhibited an advantage over both AVC and VP9 under low packet-loss scenarios. However, it is noteworthy that in our test cases, AVC outperformed HEVC and VP9 in scenarios with high packet loss, based on both subjective and objective assessments. Our observations further indicate that user preferences for the presented content contributed to video quality ratings, emphasizing the importance of additional factors that influence the perceived video quality of end users. © 2024 by the authors.

The 2024 edition of QoMEX has the motto "Towards Immersive Digiphysical Experiences". While the conference as such is organised as an on-site event, the keynotes and demonstration session(s) will be hybrid, and the demonstrations will be complemented by specific hybrid experiences. For the first time in the history of QoMEX, streaming of the keynotes will be performed using a stereoscopic 360-degree format, which can be enjoyed by a set of remote participants using Oculus headsets. This paper provides an overview of the technical solution behind this hybrid experience. It also reports on tests and qualitative user experiences obtained so far. The visitors of the demonstration and hybrid experience session will have the opportunity to take a closer look at the system, experience it in action and report the quality of their experience. © 2024 IEEE.

Författarens diskuterar hur begreppet upplevelsekvalitet kan definieras och användas konkret i en metodik inom fältet medieteknik, med exempel från undervisning på Blekinge tekniska högskola.

All virtual reality (VR) systems have some inherent hand-controller latency even when operated locally. In remotely rendered VR, additional latency may be added due to the remote transmission of data, commonly conducted through shared low-capacity channels. Increased latency will negatively affect the performance of the human VR operator, but the level of detriment depends on the given task. This work quantifies the relations between aiming accuracy and hand-controller latency, virtual target speed, and the predictability of the target motion. The tested context involves a target that changes direction multiple times while moving in straight lines. The main conclusions are, given the tested context, first, that the predictability of target motion becomes significantly more important as latency and target speed increase. A significant difference in accuracy is generally observed at latencies beyond approximately 130 ms and at target speeds beyond approximately 3.5 degrees/s. Second, latency starts to significantly impact accuracy at roughly 90 ms and approximately 3.5 degrees/s if the target motion cannot be predicted. If it can, the numbers are approximately 130 ms and 12.7 degrees/s. Finally, reaction times are on average 190-200 ms when the target motion changes to a new and unpredictable direction.

During the last decade, we have witnessed a rapiddevelopment of extended reality (XR) technologies such asaugmented reality (AR) and virtual reality (VR). Further, therehave been tremendous advancements in artificial intelligence(AI) and machine learning (ML). These two trends will havea significant impact on future digital societies. The vision ofan immersive, ubiquitous, and intelligent virtual space opensup new opportunities for creating an enhanced digital world inwhich the users are at the center of the development process,so-calledintelligent realities(IRs).The “Human-Centered Intelligent Realities” (HINTS) profileproject will develop concepts, principles, methods, algorithms,and tools for human-centered IRs, thus leading the wayfor future immersive, user-aware, and intelligent interactivedigital environments. The HINTS project is centered aroundan ecosystem combining XR and communication paradigms toform novel intelligent digital systems.HINTS will provide users with new ways to understand,collaborate with, and control digital systems. These novelways will be based on visual and data-driven platforms whichenable tangible, immersive cognitive interactions within realand virtual realities. Thus, exploiting digital systems in a moreefficient, effective, engaging, and resource-aware condition.Moreover, the systems will be equipped with cognitive featuresbased on AI and ML, which allow users to engage with digitalrealities and data in novel forms. This paper describes theHINTS profile project and its initial results. ©2023, Copyright held by the authors   

The performance of remotely rendered Virtual Reality (VR) is sensitive to temporal disturbances in communication channels. An earlier Quality of Experience (QoE) study of temporal impacts in the form of frame stalls has revealed difficulties with subjective disturbance ratings while performing a task in an interactive 6-degrees-of-freedom (DOF) VR environment. This study follows up on above observation by comparing QoE ratings in the presence and absence of a task. The exploratory findings show that the task-free subjective tests yield lower ratings compared to the subjective tests with task. This indicates that the participants became more sensitive to temporal impairments in the absence of a task. Also, the positive impact of reprojection on the QoE ratings decreased in the task-free environment. The simulator sickness results for individual symptoms were on similar low levels in both settings. The total score (TS) of sickness severity was higher after than before the subjective tests with task while the difference between the TS before and after the task-free subjective tests was insignificant, © 2023 IEEE.