Publications of the Department of Audiovisual Technology

The following list (automatically generated by the University Library) contains the publications from the year 2016. The publications up to the year 2015 can be found on an extra page.

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Results: 165
Created on: Mon, 29 Apr 2024 14:20:00 +0200 in 0.1053 sec


Arévalo Arboleda, Stephanie; Conde, Melisa; Döring, Nicola; Raake, Alexander
Introducing personas and scenarios to highlight older adults' perspectives on robot-mediated communication. - In: HRI '24 companion, (2024), S. 209-213

Little is known about the expectations of older adults (60+ years old) in robot-mediated communication when leaving aside care-related activities. To bridge this gap, we carried out 30 semi-structured interviews with older adults to explore their experiences and expectations related to technology-mediated communication. We present the results of the collected data through personas that portray three archetype users, Conny Connected, Stephan Skeptical, and Thomas TechFan. These personas are presented in a specific communication scenario with individual goals that go beyond mere communication, such as the desire for closeness (Conny Connected), a problem-free experience (Stephan Skeptical), and exploring affordances of telepresence robots (Thomas Tech-Fan). Also, we provide two considerations when aiming at positive experiences for older adults with robots: balance generalizable aspects and individual needs and identify and challenge preconceptions of telepresence robots.



https://doi.org/10.1145/3610978.3640659
Döring, Nicola; Mikhailova, Veronika; Brandenburg, Karlheinz; Broll, Wolfgang; Groß, Horst-Michael; Werner, Stephan; Raake, Alexander
Digital media in intergenerational communication: status quo and future scenarios for the grandparent-grandchild relationship. - In: Universal access in the information society, ISSN 1615-5297, Bd. 23 (2024), 1, S. 379-394

Communication technologies play an important role in maintaining the grandparent-grandchild (GP-GC) relationship. Based on Media Richness Theory, this study investigates the frequency of use (RQ1) and perceived quality (RQ2) of established media as well as the potential use of selected innovative media (RQ3) in GP-GC relationships with a particular focus on digital media. A cross-sectional online survey and vignette experiment were conducted in February 2021 among N = 286 university students in Germany (mean age 23 years, 57% female) who reported on the direct and mediated communication with their grandparents. In addition to face-to-face interactions, non-digital and digital established media (such as telephone, texting, video conferencing) and innovative digital media, namely augmented reality (AR)-based and social robot-based communication technologies, were covered. Face-to-face and phone communication occurred most frequently in GP-GC relationships: 85% of participants reported them taking place at least a few times per year (RQ1). Non-digital established media were associated with higher perceived communication quality than digital established media (RQ2). Innovative digital media received less favorable quality evaluations than established media. Participants expressed doubts regarding the technology competence of their grandparents, but still met innovative media with high expectations regarding improved communication quality (RQ3). Richer media, such as video conferencing or AR, do not automatically lead to better perceived communication quality, while leaner media, such as letters or text messages, can provide rich communication experiences. More research is needed to fully understand and systematically improve the utility, usability, and joy of use of different digital communication technologies employed in GP-GC relationships.



https://doi.org/10.1007/s10209-022-00957-w
Keller, Dominik; Ramachandra Rao, Rakesh Rao; Göring, Steve; Raake, Alexander
The effect of viewing distances on 4K and 8K HDR video quality perception. - In: IEEE Xplore digital library, ISSN 2473-2001, (2023), S. 123-130

Ongoing research in the field of capture, coding and display technology and human vision has explored the advantages of high resolution up to 8K (UHD-2) considering perceived quality. One of the crucial elements impacting users’ perception of video quality is the viewing distance. As a result, the presented study employs a subjective evaluation to investigate the perceptual benefits offered by 8K or upscaled 4K in comparison to the native 4K (UHD-1) resolution in the context of HDR videos. The subjective test uses 7 distinct viewing distances, ranging from 0.5H to 3H, with H representing the display height. The findings of the study reveal a consistent trend: the increased video quality of 8K HDR against 4K HDR content decreases with distance, on average. While there are bigger improvements for close distances, beyond 2H the quality difference was very little or zero, depending on content. In general, the degree of enhancement is contingent on the spatial complexity of the content. Additionally, it is found that, on average, subjects prefer to sit at a distance of 2.07H. No significant difference in the preferred viewing distance was found when asked before and after the study.



https://doi.org/10.1109/ISM59092.2023.00024
Ramachandra Rao, Rakesh Rao; Göring, Steve; Raake, Alexander
Adaptation of bitstream-based video quality models for image quality assessment. - In: IEEE Xplore digital library, ISSN 2473-2001, (2023), S. 230-231

In recent years, video-codec-based image codecs, such as e.g. HEF, AVF, etc., have been increasingly used to compress images. Hence, there is a potential to use video quality prediction models for the evaluation of image quality. Bitstream-based models show promising results for video quality prediction, therefore, we investigate the applicability of such models for the case of image quality in this paper. For this purpose, we selected ITU-T Rec. P.1204.3 and its Mode 0 variant also known as AVQBits|M3 and AVQBits|M0 respectively for the evaluation, because they are computationally less complex and do not need a reference image. These models are evaluated using a publicly available dataset consisting of a total of 371 images of resolutions between 144 × 144 pixels to 2160 × 2160 pixels with subjective annotations. The results show that both the considered models perform well on the used dataset with a Pearson correlation of 0.958 and Root Mean Square Error (RMSE) of 0.319 (on a 1 to 5 Absolute Category Rating (ACR) scale) for the AVQBits|M3 model and a Pearson correlation of 0.942 and RMSE of 0.377 for the AVQBits|M0 model.



https://doi.org/10.1109/ISM59092.2023.00043
Fremerey, Stephan; Zaman, Raja Faseeh Uz; Ashraf, Touseef; Ramachandra Rao, Rakesh Rao; Göring, Steve; Raake, Alexander
Towards evaluation of immersion, visual comfort and exploration behaviour for non-stereoscopic and stereoscopic 360˚ videos. - In: IEEE Xplore digital library, ISSN 2473-2001, (2023), S. 131-138

Immersion, visual comfort, and exploration behaviour are important aspects that affect the overall quality of experience for 360˚ videos. To analyze the benefits of stereoscopic and non-stereoscopic 360˚ videos in terms of these factors, we created a dataset and conducted a subjective study. The dataset consists of five different high-resolution 8 K omnidirectional videos as stereoscopic and non-stereoscopic variants. The videos have been recorded using a Kandao Obsidian Pro camera. For the comparison, we designed and performed a subjective test with 30 participants. Here, each subject watched both HEVC (libx265) encoded versions of the source video and rated the videos viewed regarding presence, visual comfort, and quality. The results indicate that with the test protocol followed, non-stereoscopic video viewing leads to slightly better presence, visual comfort, and quality ratings compared to the stereoscopic variants. Further, the stereoscopic 360˚ videos may suffer from visual artefacts potentially leading to lower video quality and further lower quality of experience results. The exploration behaviour was found to be very similar for both non-stereoscopic and stereoscopic video viewing. Overall, it can be concluded that there is a slight tendency for non-stereoscopic video viewing to be preferred over stereoscopic video viewing. The dataset is made publicly available with the paper and includes both variants of all source videos along with the subjective data, and behaviour data, following an open-science approach.



https://doi.org/10.1109/ISM59092.2023.00025
Singla, Ashutosh; Wang, Shuang; Göring, Steve; Ramachandra Rao, Rakesh Rao; Viola, Irene; Cesar, Pablo; Raake, Alexander
Subjective quality evaluation of point clouds using remote testing. - In: IXR '23, (2023), S. 21-28

Subjective quality assessment serves as a method to evaluate the perceptual quality of 3D point clouds. These evaluations can be conducted using lab-based or remote or crowdsourcing tests. The lab-based tests are time-consuming and less cost-effective. As an alternative, remote or crowd tests can be used, offering a time and cost-friendly approach. Remote testing enables larger and more diverse participant pools. However, this raises the question of its applicability due to variability in participants' display devices and environments for the evaluation of the point cloud. In this paper, the focus is on investigating the applicability of remote testing by using the Absolute Category Rating (ACR) test method for assessing the subjective quality of point clouds in different tests. We compare the results of lab and remote tests by replicating lab-based tests. In the first test, we assess the subjective quality of a static point cloud geometry for two different types of geometrical degradations, namely Gaussian noise, and octree-pruning. In the second test, we compare the performance of two different compression methods (G-PCC and V-PCC) to assess the subjective quality of coloured point cloud videos. Based on the results obtained using correlation and Standard deviation of Opinion Scores (SOS) analysis, the remote testing paradigm can be used for evaluating point clouds.



https://doi.org/10.1145/3607546.3616803
Breuer, Carolin; Leist, Larissa; Fremerey, Stephan; Raake, Alexander; Klatte, Maria; Fels, Janina
Towards investigating listening comprehension in virtual reality. - Aachen : Universitätsbibliothek der RWTH Aachen. - 1 Online-Ressource (7 Seiten)

The investigation of listening comprehension in auditory and visually complex classroom settings is a promising method to evaluate children’s cognitive performance in a realistic setting. Many studies were able to show that children are more susceptible to noise than adults. However, it has recently been suggested that established monaural listening situations could overestimate the influence of noise on children’s task performance. Therefore, new, close- to real-life scenarios need to be introduced to investigate cognitive performance in everyday situations rather than artificial laboratory settings. This study aimed at extending a validated paper-and-pencil test towards a virtual reality setting. To get first insights, into different interaction methods, a pilot study with adult participants was conducted. In contrast to other recent studies, the virtual environment had little influence on this listening comprehension paradigm, since comparable results were obtained in the paper-and-pencil test and in the virtual reality variants for all user interfaces. Thus, the presented paradigm has proven to be robust and can be used to further investigate the usage of virtual reality to evaluate children’s cognitive performance.



https://doi.org/10.18154/RWTH-2023-11913
Ramachandra Rao, Rakesh Rao; Göring, Steve; Elmeligy, Bassem; Raake, Alexander
AVT-VQDB-UHD-1-Appeal: a UHD-1/4K open dataset for video quality and appeal assessment using modern video codecs. - In: IEEE Xplore digital library, ISSN 2473-2001, (2023), insges. 6 S.

A number of factors play an important role in the perception of video quality for streaming and other services, key among them being encoding-related degradations. Hence, newer codecs are developed with the goal of optimizing video quality for a given encoding setting. Here, subjective studies are an efficient method to evaluate the performance of such newer codecs. Furthermore, contextual factors impact the perception of video quality, e.g., the appeal of the content itself. To this end, this paper presents a subjective study targeting both quality and appeal assessment of videos. For this purpose, a subjective study consisting of three different parts is conducted. Firstly, participants were asked to rate the appeal of the uncompressed UHD-1/4K source content with a duration of 8 - 10s each. Following this, the video quality of these source videos individually encoded with either the HEVC/H.265, AV1, or VVC/H.266 video codec was rated. A wide range of encoding conditions in terms of resolution (360p to 2160p) and bitrate (100kbps to 15mbps) is used to encode the videos, so as to enable the applicability of the data to real-world settings. In the last part, subjects are again asked to rate the appeal of the uncompressed source content. The results are analyzed to assess the impact of different encoding conditions on perceived video quality. In addition, the impact of appeal on video quality and vice-versa is also investigated. Furthermore, an objective quality assessment with different state-of-the-art full-reference, bitstream-based, and hybrid models including the newer codecs AV1 and VVC is presented. The subjective dataset including test design, subjective results, sources, and encoded audiovisual contents are made publicly available following an open science approach.



https://doi.org/10.1109/MMSP59012.2023.10337713
Viola, Irene; Amirpour, Hadi; Arévalo Arboleda, Stephanie; Torres Vega, Maria
IXR '23: 2nd International Workshop on Interactive eXtended Reality. - In: MM '23, (2023), S. 9728-9730

Despite remarkable advances, current Extended Reality (XR) applications are in their majority local and individual experiences. A plethora of interactive applications, such as teleconferencing, telesurgery, interconnection in new buildings project chain, Cultural Heritage, and Museum contents communication, are well on their way to integrating immersive technologies. However, interconnected, and interactive XR, where participants can virtually interact across vast distances, remains a distant dream. In fact, three great barriers stand between current technology and remote immersive interactive life-like experiences, namely (i) content realism, (ii) motion-to-photon latency, and accurate (iii) human-centric quality assessment and control. Overcoming these barriers will require novel solutions at all elements of the end-to-end transmission chain. This workshop focuses on the challenges, applications, and major advancements in multimedia, networks, and end-user infrastructures to enable the next generation of interactive XR applications and services.



https://doi.org/10.1145/3581783.3610945
Fischedick, Söhnke B.; Richter, Kay; Wengefeld, Tim; Seichter, Daniel; Scheidig, Andrea; Döring, Nicola; Broll, Wolfgang; Werner, Stephan; Raake, Alexander; Groß, Horst-Michael
Bridging distance with a collaborative telepresence robot for older adults - report on progress in the CO-HUMANICS project. - In: ISR Europe 2023: 56th International Symposium on Robotics, (2023), S. 346-353

In an aging society, the social needs of older adults, such as regular interactions and independent living, are crucial for their quality of life. However, due to spatial separation from their family and friends, it is difficult to maintain social relationships. Our multidisciplinary project, CO-HUMANICS, aims to meet these needs, even over long distances, through the utilization of innovative technologies, including a robot-based system. This paper presents the first prototype of our system, designed to connect family members or friends virtually present through a mobile robot with an older adult. The system incorporates bi-directional video telephony, remote control capabilities, and enhanced visualization methods. A comparison is made with other state-of-the-art robotic approaches, focusing on remote control capabilities. We provide details about the hard- and software components, e.g., a projector-based pointing unit for collaborative telepresence to assist in everyday tasks. Our comprehensive scene representation is discussed, which utilizes 3D NDT maps, enabling advanced remote navigation features, such as autonomously driving to a specific object. Finally, insights about past and concepts for future evaluation are provided to assess the developed system.



https://ieeexplore.ieee.org/document/10363093