Jesús Gutiérrez

Universidad Politécnica de Madrid | UPM · Departamento de Señales, Sistemas y Radiocomunicaciones

Immersive technologies like eXtended Reality (XR) are the next step in videoconferencing. In this context, understanding the effect of delay on communication is crucial. This paper presents the first study on the impact of delay on collaborative tasks using a realistic Social XR system. Specifically, we design an experiment and evaluate the impact...

Welcome to a new column on the ACM SIGMM Records from the Video Quality Experts Group (VQEG).

Welcome to this new column on the ACM SIGMM Records from the Video Quality Experts Group (VQEG), which will provide an overview of the last VQEG plenary meeting that took place from 9 to 13 May 2022. It was organized by INSA Rennes (France), and it was the first face-to-face meeting after the series of online meetings due to the Covid-19 pandemic....

p>Respiratory diseases in children under the age of two, such as bronchiolitis or pneumonia, are a major cause of emergency consultations in hospital and primary care settings, being also a significant cause of mortality in low-income countries. Early detection of respiratory distress and high respiratory rate is crucial for timely intervention and...

This paper presents a comparison between three content-immersive methodologies to evaluate video quality: Absolute Category Rating (ACR) with unrepeated scenes, Single Stimulus Continuous Quality Evaluation (SSCQE), and Single Stimulus Discrete Quality Evaluation (SSDQE). Three tests were conducted with different participants assigned to each metho...

Welcome to the fifth column on the ACM SIGMM Records from the Video Quality Experts Group (VQEG). The last VQEG plenary meeting took place online from 7 to 11 June 2021. As the previous meeting celebrated in December 2020, it was organized online (this time by Kingston University) with multiple sessions spread over five days, allowing remote partic...

Quality assessment is a key element for the evaluation of hardware and software involved in image and video acquisition, processing, and visualization. In the medical field, user-based quality assessment is still considered more reliable than objective methods, which allow the implementation of automated and more efficient solutions. Regardless of...

Several technological and scientific advances have been achieved recently in the fields of immersive systems (e.g., 360-degree/multiview video systems, augmented/mixed/virtual reality systems, immersive audio-haptic systems, etc.), which are offering new possibilities to applications and services in different communication domains, such as entertai...

Several technological and scientific advances have been achieved recently in the fields of immersive systems, which are offering new possibilities to applications and services in different communication domains, such as entertainment, virtual conferencing, working meetings, social relations, healthcare, and industry. Users of these immersive techno...

This paper proposes a methodology to assess video quality, spatial and social presence, empathy, attitude, and attention in 360-degree videos for immersive communications. The methodology is validated in an experiment which simulates an immersive communication environment where participants attend three conversations of different genre (everyday co...

Recently an impressive development in immersive technologies, such as Augmented Reality (AR), Virtual Reality (VR) and 360 video, has been witnessed. However, methods for quality assessment have not been keeping up. This paper studies quality assessment of 360 video from the cross-lab tests (involving ten laboratories and more than 300 participants...

This paper analyzes the joint assessment of quality, spatial and social presence, empathy, attitude, and attention in three conditions: (A)visualizing and rating the quality of contents in a Head-Mounted Display (HMD), (B)visualizing the contents in an HMD,and (C)visualizing the contents in an HMD where participants can see their hands and take not...

Light Field imaging provides a wide range of interactive features, such as view point changing and refocusing, and it has been developing as a solution for six degree of freedom applications. Many ongoing efforts, specifically related to pre/post processing, compression, and rendering, have been devoted to the development of this technology. To ben...

The recent studies showing that gaze features can be useful in the identification of Autism Spectrum Disorder (ASD), have opened a new domain where Visual Attention (VA) modeling could be of great help. In this sense, this paper presents a report of the Grand Challenge “Saliency4ASD: Visual attention modeling for Autism Spectrum Disorder”, organize...

With the coming of age of virtual/augmented reality and interactive media, numerous definitions, frameworks, and models of immersion have emerged across different fields ranging from computer graphics to literary works. Immersion is oftentimes used interchangeably with presence as both concepts are closely related. However, there are noticeable int...

This paper presents a study on Quality of Experience (QoE) evaluation of 3D objects in Mixed Reality (MR) scenarios. In particular , a subjective test was performed with Microsoft HoloLens, considering different degradations affecting the geometry and texture of the content. Apart from the analysis of the perceptual effects of these artifacts, give...

This paper presents a system and methodology for the analysis of Quality of Experience (QoE) factors for dense multiview (MV) video using a Head-Mounted Device (HMD). An MV-HMD player has been designed and implemented to immerse the users in a virtual environment, where they are placed in front of a virtual lightfield display that shows a different...

Social difficulties are the hallmark features of Autism Spectrum Disorder (ASD) and can lead to atypical visual attention towards stimuli. Eye movements encode rich information about attention and psychological factors of an individual, which could help to characterize the traits of ASD. Learning atypical eye movements of the individuals with ASD t...

Free-Viewpoint Video (FVV) systems allow the viewers to freely change the viewpoints of the scene. In such systems, view synthesis and compression are the two main sources of artifacts influencing the perceived quality. To assess this influence, quality evaluation studies are often carried out using conventional displays and generating predefined n...

Free-Viewpoint Video (FVV) systems allow the viewers to freely change the viewpoints of the scene. In such systems, view synthesis and compression are the two main sources of artifacts influencing the perceived quality. To assess this influence, quality evaluation studies are often carried out using conventional displays and generating predefined n...

Research on visual attention in 360° content is crucial to understand how people perceive and interact with this immersive type of content and to develop efficient techniques for processing, encoding, delivering and rendering. And also to offer a high quality of experience to end users. The availability of public datasets is essential to support an...

Research on understanding how people watch/explore Virtual Reality (VR) and 360° content is crucial to develop appropriate technologies for processing, encoding, delivering and rendering media content in order to provide high-quality immersive experiences to users. In this sense, the work described in this paper aims at supporting the research on v...

Understanding how observers watch visual stimuli like Images and Videos has helped the multimedia encoding, transmission, quality assessment and rendering communities immensely, to learn the regions important to an observer and provide to him/her an optimum quality of experience. The problem is even more paramount in case of 360 degree stimuli cons...

The subjective assessment of super multiview (SMV) video considers two main perceptual factors: image quality and visual comfort at the viewpoint transition. While previous works only covered raw content with high levels of visual comfort, this work supersedes them targeting the subjective assessment of SMV content with coding artifacts. The outcom...

Super MultiView (SMV) video display is the most promising technology for 3D glasses-free visualization. Although only a few prototypes are currently available, the research on technical and perceptual factors related to this approach is crucial. This paper presents a novel model to capture the subjective perception of SMV, called MultiView Perceptu...

This paper presents a 3D video dataset containing sequences with typical content from videoconferencing scenarios. The objective of this dataset is to provide freely-available sequences for the research community to support the development and evaluation of processing techniques applicable to 3D videoconferencing systems. Therefore, a detailed desc...

This paper presents a comparison among different consumer 3D display technologies by means of a subjective assessment test. Therefore, four 55-in displays have been considered: one autostereoscopic display, one stereoscopic with polarized passive glasses, and two with active shutter glasses. In addition, a high-quality 3D video database has been us...

The usage of HTTP adaptive streaming (HAS) has become widely spread in multimedia services. Because it allows the service providers to improve resource utilization and user's Quality of Experience (QoE). Using this technology , the video playback interruption is reduced since the network and server status in addition to capability of user device, a...

We present preliminary experiments on subjective evaluation of Super Multiview Video (SMV) in stereoscopic and auto-stereoscopic displays. SMV displays require a large number of views (typically 80 or more), but are not yet widely available. Subjective evaluation in legacy displays, though not optimal, will therefore be necessary for the developmen...

Lately, several algorithms have been proposed to automatically estimate the quality of video sequences, even some have been included in international standards. However, the majority only provide high performance under particular conditions and with certain types of degradations. Therefore, some proposals have been presented setting out the combina...

Nowadays, HTTP adaptive streaming (HAS) has become a reliable distribution technology offering significant advantages in terms of both user perceived Quality of Experience (QoE) and resource utilization for content and network service providers. By trading-off the video quality, HAS is able to adapt to the available bandwidth and display requiremen...

A frame-level distortion model based on perceptual features of the human visual system is proposed to improve the performance of unequal error protection strategies and provide better quality of experience to users in Side-by-Side 3D video delivery systems.

In recent years, multimedia applications and services, especially video, have suffered a sudden growth. Today, the video display is not limited to the traditional areas of movies and television, but thanks to the evolution of video distribution for packet networks such as the Internet, and the emergence of numerous and various video display devices...

The streaming of 3D video contents is currently a reality to expand the user experience. However, because of the variable bandwidth of the networks used to deliver multimedia content, a smooth and high-quality playback experience could not always be guaranteed. Using segments in multiple video qualities, HTTP adaptive streaming (HAS) of video conte...

Although the delivery of 3D video services to households is nowadays a reality thanks to frame-compatible formats, many efforts are being made to obtain efficient methods to transmit 3D content offering a high quality of experience to the end users. In this paper, a stereoscopic video streaming scenario is considered, and the perceptual impact of v...

Research in stereoscopic 3D coding, transmission and subjective assessment methodology depends largely on the availability of source content that can be used in cross-lab evaluations. While several studies have already been presented using proprietary content, comparisons between the studies are difficult since discrepant contents are used. Therefo...

Transmission errors are the main cause of degradation of the quality of real broadcasted video services. Therefore, knowing their impact on the quality of experience of the end users is a crucial issue. For instance, it would help to improve the performance of the distribution systems, and to develop monitoring tools to automatically estimate the q...

Recently, three-dimensional (3D) video has decisively burst onto the entertainment industry scene, and has arrived in households even before the standardization process has been completed. 3D television (3DTV) adoption and deployment can be seen as a major leap in television history, similar to previous transitions from black and white (B&W) to col...

Considering a scalable video quality monitoring architecture to detect transmission errors at households, we propose a technique to detect packet losses in IPTV and Side-by-Side 3DTV and evaluate their impact on the perceived quality.

Real-time monitoring of multimedia Quality of Experience is a critical task for the providers of multimedia delivery services: from television broadcasters to IP content delivery networks or IPTV. For such scenarios, meaningful metrics are required which can generate useful information to the service providers that overcome the limitations of pure...

The increase of multimedia services delivered over packet-based networks has entailed greater quality expectations of the end-users. This has led to an intensive research on techniques for evaluating the quality of experience perceived by the viewers of audiovisual content, considering the different degradations that it could suffer along the broad...

Recently, broadcasted D video content has reached households with the first generation of 3DTV. However, few studies have been done to analyze the Quality of Experience (QoE) perceived by the end-users in this scenario. This paper studies the impact of transmission errors in 3DTV, considering that the video is delivered in side-by-side format over...