3D video quality of experience - influence of scale and crosstalk

This paper gives an overview of three recent studies by the authors on the topic of 3D video Quality of Experience (QoE). Two of studies [1,2] investigated different psychological dimension that may be needed for describing 3D video QoE and the third the visibility and annoyance of crosstalk[3]. The results shows that the video quality scale could be sufficient for evaluating S3D video experience for coding and spatial resolution reduction distortions. It was also confirmed that with a more complex mixture of degradations more than one scale should be used to capture the QoE in these cases. The study found a linear relationship between the perceived crosstalk and the amount of crosstalk

Objective video quality assessment methods for Video assistant refereeing (VAR) Systems

This report describes the work and conclusions drawn after phase 4 in the project “Assessment methods for Video assistant refereeing (VAR) System”. The performance of six different video quality models have been evaluated, that were identified during phase 1, against the subjective video quality database that was created during phase 3. The results are slightly different for 1080p compared to 1080i. For 1080p the models VQM_VFD, SSIM and VMAF performs the best with Pearson Correlation Coefficients (PCC) above 0.9. For 1080i the PCC drops a bit overall and then VMAF and VQM_VFD are close in performance and performing the best. The overall performance for both formats VMAF an VQM_VFD stands out as the best models. In this comparison VQM_VFD has the added advantage to also be able to perform its own registration i.e. to fix any misalignment between the reference video and the distorted one

Video quality based on a user study with video professionals for Video Assisted Refereeing (VAR) Systems

This document describes a user experiment with the purpose of finding a baseline quality that is suitable for system and a database for training and evaluating the objective quality measurement methods suitable for assessing the video quality of VAR systems.  A user experiment was performed involving 25 Swedish video experts. Three different video formats were incorporated 1080p, 1080i and 540i. The degradations were in most cased done using encoding with Motion JPEG (MJPEG) and H.264 in the bitrate range from 80 Mbit/s down to 10 Mbit/s.  MJPEG loses quality very fast and already at 80 Mbit/s it has significantly lower quality than the uncompressed reference and then for even lower bitrates the quality falls quickly to bad. On the other hand, H.264 was not found to be significant different from the uncompressed reference until the bitrate had dropped to 10 Mbit/s for 1080p. For 1080i 20 Mbit/s was also weakly and for 540i 20 Mbit/s was significantly lower for some of the scaling methods. For 1080i the deinterlacing requires careful consideration, since the deinterlacing scheme introduced received very low quality scores. For the scaling scheme lanczos was the best and bilinear the worst.  Requirement levels on bitrate and the encoders MJPEG and H.264 based on this experiment•    MJPEG require more than 120 Mbit/s•    H.264 require more than 50 Mbit/

A comparison of visual ergonomic measurements between active and passive 3DTV

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A comparison of visual ergonomic measurements between active and passive 3DTV

The two latest 3DTV types were tested; active shutter eye-glass type and passive eye-glass type with screen having film pattern retarder. Differences in vertical resolution, cross-talk and luminance were found. This difference in vertical resolution is visible for some types of objects. How this affects the image quality is unclear

Crosstalk Measurements of Shutter Glasses 3D Displays

Crosstalk is probably one of the main perceptual factors contributing to perceived image quality and visual comfort. The Video Quality Experts Group (VQEG) within their 3D video quality project is specifying a practical measurement procedure that will produce consistent results across laboratories. This paper is part of that effort. Two different method of measuring cross talk on shutter glasses stereo displays have been studied. One is based on time average luminance measurements and the other on temporal measurements. The results show that crosstalk is roughly 0.5% but that there are differences in the crosstalk between the two eyes in the shutter glasses

Recommended precautions because of Covid-19 for perceptual, behavioural,quality and user experience experimentswith test persons in indoor labs

Based on the recommendations from the Public Health Agency of Sweden(Folkhälsomyndigheten; FHM) and a set of internal rules from RISE, the followingrules are published for how to conduct experiments involving test persons in the timesof the pandemic Covid-19. The recommendations are for non-invasive and non-medicaltests, e.g. perceptual, consumer, ergonomic and human-computer interaction teststaking place in an indoor laboratory. Specifically, in this document we are specifying how experiments with test personstargeting audio and visual presentations should be done considering necessaryprecautions imposed by the Covid-19 pandemic. Laboratory experiments with testpersons, as it involves inviting people to the lab, require particular planning and carefulconsideration, if they are to be carried out safely because of the risks imposed by theCovid-19 pandemic. The safety aspects are valid for both the invited test persons andare equally important for the health of the test leaders

Video expert assessment of high quality video for Video Assistant Referee (VAR) : A comparative study

The International Football Association Board decided to introduce Video Assistant Referee (VAR) in 2018. This led to the need to develop methods for quality control of the VAR-systems. This article focuses on the important aspect to evaluate the video quality. Video Quality assessment has matured in the sense that there are standardized, commercial products and established open-source solutions to measure it with objective methods. Previous research has primarily focused on the end-user quality assessment. How to assess the video in the contribution phase of the chain is less studied. The novelties of this study are two-fold: 1) The user study is specifically targeting video experts i.e., to assess the perceived quality of video professionals working with video production. 2) Six video quality models have been independently benchmarked against the user data and evaluated to show which of the models could provide the best predictions of perceived quality. The independent evaluation is important to get unbiased results as shown by the Video Quality Experts Group. An experiment was performed involving 25 video experts in which they rated the perceived quality. The video formats tested were High-Definition TV both progressive and interlaced as well as a quarters size format that was scaled down half the size in both width and height. The videos were encoded with both H.264 and Motion JPEG for the full size but only H.264 for the quarter size. Bitrates ranged from 80 Mbit/s down to 10 Mbit/s. We could see that for H.264 that the quality was overall very good but dropped somewhat for 10 Mbit/s. For Motion JPEG the quality dropped over the whole range. For the interlaced format the degradation that was based on a simple deinterlacing method did receive overall low ratings. For the quarter size three different scaling algorithms were evaluated. Lanczos performed the best and Bilinear the worst. The performance of six different video quality models were evaluated for 1080p and 1080i. The Video Quality Metric for Variable Frame Delay had the best performance for both formats, followed by Video Multimethod Assessment Fusion method and the Video Quality Metric General model. This work was funded by Fédération Internationale de Football Association (FIFA) and Sweden´s Innovation Agency (VINNOVA, dnr. 2021-02107) through the Celtic-Next project IMMINENCE (C2020/2-2), which is hereby gratefully acknowledged.</p

Video quality of video professionals for Video Assisted Referee (VAR)

Changes in the footballing world’s approach to technology and innovation contributed to the decision by the International Football Association Board to introduce Video Assistant Referees (VAR). The change meant that under strict protocols referees could use video replays to review decisions in the event of a "clear and obvious error" or a "serious missed incident". This led to the need by Fédération Internationale de Football Association (FIFA) to develop methods for quality control of the VAR-systems, which was done in collaboration with RISE Research Institutes of Sweden AB. One of the important aspects is the video quality. The novelty of this study is that it has performed a user study specifically targeting video experts i.e., to measure the perceived quality of video professionals working with video production as their main occupation. An experiment was performed involving 25 video experts. In addition, six video quality models have been benchmarked against the user data and evaluated to show which of the models could provide the best predictions of perceived quality for this application. Video Quality Metric for variable frame delay (VQM_VFD) had the best performance for both formats, followed by Video Multimethod Assessment Fusion (VMAF) and VQM General model.This work was mainly funded by Fédération Internationale de Football Association (FIFA) and partly supported by the Sweden´s Innovation Agency (VINNOVA, dnr. 2021-02107) through the Celtic-Next project IMMINENCE (C2020/2-2) as well as RISE internal funding. </p