Audiovisual Database with 360 Video and Higher-Order Ambisonics Audio for Perception, Cognition, Behavior, and QoE Evaluation Research

Research into multi-modal perception, human cognition, behavior, and attention can benefit from high-fidelity content that may recreate real-life-like scenes when rendered on head-mounted displays. Moreover, aspects of audiovisual perception, cognitive processes, and behavior may complement questionnaire-based Quality of Experience (QoE) evaluation of interactive virtual environments. Currently, there is a lack of high-quality open-source audiovisual databases that can be used to evaluate such aspects or systems capable of reproducing high-quality content. With this paper, we provide a publicly available audiovisual database consisting of twelve scenes capturing real-life nature and urban environments with a video resolution of 7680x3840 at 60 frames-per-second and with 4th-order Ambisonics audio. These 360 video sequences, with an average duration of 60 seconds, represent real-life settings for systematically evaluating various dimensions of uni-/multi-modal perception, cognition, behavior, and QoE. The paper provides details of the scene requirements, recording approach, and scene descriptions. The database provides high-quality reference material with a balanced focus on auditory and visual sensory information. The database will be continuously updated with additional scenes and further metadata such as human ratings and saliency information.Comment: 6 pages, 2 figures, accepted and presented at the 2022 14th International Conference on Quality of Multimedia Experience (QoMEX). Database is publicly accessible at https://qoevave.github.io/database

Subjective quality evaluation of Point Clouds using remote testing

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

QUALINET white paper on definitions of Immersive Media Experience (IMEx)

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 interdisciplinary differences regarding definitions, scope, and constituents that are required to be addressed so that a coherent understanding of the concepts can be achieved. Such consensus is vital for paving the directionality of the future of immersive media experiences (IMEx) and all related matters. The aim of this white paper is to provide a survey of definitions of immersion and presence which leads to a definition of immersive media experience (IMEx). The Quality of Experience (QoE) for immersive media is described by establishing a relationship between the concepts of QoE and IMEx followed by application areas of immersive media experience. Influencing factors on immersive media experience are elaborated as well as the assessment of immersive media experience. Finally, standardization activities related to IMEx are highlighted and the white paper is concluded with an outlook related to future developments

Bipartitioning for Hybrid FPGA-Software Simulation

Simulation is an important step in the design cycle of VLSI systems. The increasing size and complexity of modern systems require simulation techniques optimized for time. Researchers are resorting to parallel simulation to reduce simulation time. Logic partitioning plays an important role in parallel simulation. Two factors, concurrency amongst the partitions and communication between them, determine the effectiveness of partitioning. The concurrency achieved and the communication overhead resulting from the intersecting signals can directly affect the speed-up achieved in the simulation. Hybrid FPGA-software simulation offers an alternative for increasing the speed of simulation. In addition to above factors, size and cost of FPGA also determine the partitioning technique for FPGA based emulation. This paper addresses the issues involved in hybrid FPGA-software simulation and presents a new partitioning scheme. With our approach, communication between partitions reduces to at least 5..

Comparative efficacy of application of three different desensitizing agents with iontophoresis in the treatment of hypersensitive teeth

Background: The purpose of this study was to compare the efficacy of sodium fluoride, strontium chloride, methyl prednisolone, and distilled water (control) with iontophoresis in treating hypersensitivity. Materials and Methods: The study recruited 64 subjects fulfilling inclusion and exclusion criteria who were evaluated for hypersensitivity using tactile, air blast, and cold water tests. The subjects were randomly divided into four groups - group A: 2% sodium fluoride, group B: 10% strontium chloride, group C: 0.125% methyl prednisolone, and group D: distilled water (control). The subjects were evaluated for 6 weeks and their responses were recorded on the verbal rating scale. All the reagents were administered through iontophoresis. In the in vitro study, a total of 32 dentin specimens were obtained, which were randomly divided into four groups. The above mentioned reagents were applied onto the dentin specimens through iontophoresis, the unit of which was available in the department, and were evaluated under a scanning electron microscope (SEM). Results: After the statistical analysis, it was found that comparison between group A and group B was nonsignificant, whereas comparison between groups A and C, groups A and D, groups B and C, groups B and D, and groups C and D were significant. In SEM analysis, maximum numbers of occluded tubules were seen with sodium fluoride. Conclusions: Clinically, a single application of iontophoresis with 2% sodium fluoride, 10% strontium chloride, and 0.125% methyl prednisolone proved to be a better therapeutic agent in comparison with distilled water. The SEM results also related with clinical finding in that reduction in the patency of tubules was associated with improvement in treatment efficacy

A Lossless Image Prediction Algorithm using Slope Estimation and Least Square Optimization

In this paper we present two computationally simple algorithms that can be used for prediction of pixels of images. In one of the algorithms, prediction is made by estimating intensity value variations in four directions and their reciprocals are used to make prediction of unknown pixel. This algorithm captures local characteristics of the unknown pixel well as it uses only a small number of neighborhood pixels. The other algorithm finds slope as the relative intensity-value variations and classifies image pixels in fourteen bins by classifying the slope in the same number of bins. LS based predictors are estimated for pixels belonging to each of the bins and hence the they represent global characteristics of these pixels. Since one algorithm takes care of local characteristics while the other one represents global feature, we propose a switching method for these two algorithms that takes advance of both the algorithms. Switching is done on a pixel-by-pixel basis and the same gives approximately 0.10 bpp better performance as compared to some of the computationally complex methods reported in literature at a lower computational complexity

Adaptive Predictor Structures for Lossless Compression of Videos

In this paper, we propose a prediction algorithm that uses adaptive predictor structures for loss less video coding. The proposed encoder finds cross-correlation coefficient between current frame and motion compensated previous frame and classifies the coefficient value into a small number of bins. For general videos, we propose four bins and associate different predictor structures with each of the bins. Similarly for medical videos, numbers of bins are three and each of these bins is associated with different predictor structures. Performance of our method is compared with the fixed predictor structure used in practice and found that the proposed method not only gives better prediction performance but it is computational efficient as compared to fixed predictor structure. © 2012 IEEE