Optimal Carrier Loading Control for the Enhancement of Visual Quality over OFDMA Cellular Networks

IEEE Trans. on Image Process.

et al. 2013

Self Cite

120

Abstract-It is generally recognized that severe video distortions that are transient in space and/or time have a large effect on overall perceived video quality. In order to understand this phenomena, we study the distribution of spatio-temporally local quality scores obtained from several video quality assessment (VQA) algorithms on videos suffering from compression and lossy transmission over communication channels. We propose a content adaptive spatial and temporal pooling strategy based on the observed distribution. Our method adaptively emphasizes "worst" scores along both the spatial and temporal dimensions of a video sequence and also considers the perceptual effect of largearea cohesive motion flow such as egomotion. We demonstrate the efficacy of the method by testing it using three different VQA algorithms on the LIVE Video Quality database and the EPFL-PoliMI video quality database.

Section: A Distribution Of Spatio-temporal Video Qualitymentioning

confidence: 63%

Video Quality Pooling Adaptive to Perceptual Distortion Severity

Park

Seshadrinathan

IEEE Trans. on Image Process.

et al. 2013

Self Cite

120

“…Fig. 8 shows the average SSIMs of users according to the frame number for IBSA and MMFA when a passive error concealment method is applied based on previous error concealment experiments [17], [31], [32]. Fig.…”

Section: Numerical Resultsmentioning

confidence: 99%

Optimal Beam Steering for Maximal Visual Quality Over a Multimedia Broadcasting System

Kim

IEEE Trans. on Broadcast.

et al. 2016

Self Cite

Various types of multimedia services have become prominent over the last few years leading to difficulty in providing high-quality broadcast multimedia services in certain shadowing regions without resource management in accordance with specific channel adaptation. In order to overcome this difficulty, return channel design has been actively discussed in broadcasting standards for broadcasting systems. Context-aware multimedia services have been developed by adapting radio resources according to service type. In order to forward this goal, we propose a beamforming technique to optimize spatial resources in order to maximize visual quality for video broadcasting services. In order to enhance the video broadcast service, we derive expected visual information (EVI) that quantifies the visual quality of video and adapt the EVI into multiple-input and multiple-output beamforming techniques in a video broadcast system. In order to guarantee the proportional fairness of broadcast users, we propose a novel beam steering algorithm using the log-EVI sum maximization, and compare it to the traditional channel-quality-based max-min problem. The beamsteering algorithm is performed iteratively while switching the bases, which constructs a beam steering weight vector domain. In the simulation, we demonstrate that the proposed algorithm has less computational complexity than conventional algorithms, and the visual quality of the proposed algorithm is enhanced over that of the traditional quasi-optimal max-min fairness algorithm.Index Terms-Multiple-input and multiple-output (MIMO) systems, multimedia broadcast systems, beam steering, expected visual information (EVI), non-convex problem.

“…13(d)-(f). Visual entropy in [14][15][16] is used as the quality metric for the evaluation of video quality. The values of 'visual entropy' show that (d)-(f) have the better quality than (a)-(c) and we can therefore improve the visual quality by using both the artPS class and the layered coding scheme.…”

Section: Normalixed Distancementioning

confidence: 99%

Definition of a new service class, artPS for video services over WiBro/Mobile WiMAX systems

2010

Wireless Netw

Self Cite

Increased development in the area of networking has coincided with an increased demand for multimedia services via high data rates. Nevertheless, adaptation of the current volume of multimedia data to capacity-limited commercial wireless networks has not kept pace. The Wireless Broadband (WiBro)/Mobile Worldwide Interoperability for Microwave Access (WiMAX) system, which is expected to be one of the platforms for 4G wireless communications, entertains several kinds of service classes with respect to the characteristics of services. However, no effective techniques have been specified to deal with the quality degradation that occurs in conjunction with either dynamic channel fluctuation or throughput dropping at the cell edge over highly error-prone channel environments. In this paper, we define a new service class, advanced real-time Polling Service (artPS), that adapts to the channel variation by introducing layered coding like Scalable Video Coding. Utilizing this artPS class, the proposed system very efficiently achieves higher Quality of Service, while maintaining backward compatibility with the conventional system and attaining the multiplexing gain of layered data.