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This paper presents a new Scalable Video Codec (SVC)-based hybrid adaptive video streaming scheme, named HAVS, for mobile devices in wireless environments. The proposed approach takes two existing video streaming technologies, viz., progressive download and adaptive streaming, and switches them in a hybrid manner. To this end, HAVS employs the H.264/SVC encoding scheme, where each video chunk is encoded into one base layer and several enhancement layers. Since clients request the base layer every time a video is streamed, HAVS performs progressive download for the base layer and adaptive streaming for the enhancement layers. Through wireless test-bed experiments, it is demonstrated that the proposed scheme can be easily implemented on mobile devices without any server-side modification. This scheme effectively prevents video freeze thereby providing better quality video streaming than the existing non-hybrid streaming technologies. [ABSTRACT FROM PUBLISHER]

Designing a real-time video-streaming system involves the challenges of, network congestion and bandwidth fluctuations, lowering the video quality. In this paper, a realtime video-streaming system is designed and implemented for scalable video coding (SVC) with an adaptive control scheme, containing macro- and micro-control, to resolve the bandwidth fluctuation and network congestion. Under macro-control, the server allocates appropriated video-streaming of SVC for heterogeneous clients based on terminal capacity and network conditions. Under micro-control, the server changes the video frame rate based on video bit rates and network bandwidth. The streaming system with the adaptive control scheme is implemented to improve the peak signal noise ratio (PSNR) by 4.01 % to 10.89 % of the Foreman and Stefan videos. [ABSTRACT FROM AUTHOR]

Ultra-high definition (UHD) which has 4 to 16 times as many pixels as existing high definition (HD) is expected as a next generation video format. To deliver UHD and HD videos simultaneously in the communications-broadcasting convergence environment, scalable video coding (SVC) is a highly attractive solution. We propose an improved scalable video coding method to achieve high coding efficiency particularly for UHD and HD videos. The basic idea is to allow large block size beyond the block size of 16x16 pixels in H.264/AVC SVC, which results in more efficient inter-layer prediction and syntax elements coding. The experimental results show that it achieves an average 5.34% reduction in BD-rate relative to H.264/AVC SVC. [ABSTRACT FROM PUBLISHER]

We propose a new disk power management scheme for scalable video coding (SVC) video playback. Conventional disk power management techniques for video players usually prefetch video frames into buffer to allow disk to enter low-power mode, which may require significant buffer space. To address this, we exploit temporal scalability property in which multiple frame rates for the same video stream are provided, and allow selective frame prefetching with the aim of achieving specified quality levels while reducing disk energy consumption. Simulation results show that the disk energy consumption can be reduced by 8.4% on average without any noticeable quality degradation by users. [ABSTRACT FROM PUBLISHER]

In home networks, seamless networking and collaborative streaming-based multimedia content sharing have become challenging issues in providing QoS (Quality of Service) for its users with heterogeneous consumer electronic devices. In order to support the demands for QoS, recently SVC (Scalable Video Coding) scheme has attracted attention. However, existing schemes do not guarantee the quality of multimedia contents as these schemes do not consider the characteristics of the SVC encoding scheme. Moreover, they do not accurately estimate the available network bandwidth. To cope with these problems, this paper presents a simple but effective N-QA (Network-aware Quality Adaptation) scheme that can improve the quality of streaming contents in a device collaboration service. The proposed scheme quickly adjusts the data transmission rate according to the estimated available bandwidth of network. It also controls media quality using SVC characteristics. The experimental result shows that the proposed scheme can significantly improve the media quality. [ABSTRACT FROM PUBLISHER]

The pace at which powerful portable wireless consumer devices such as smartphones and tablets have been adopted has not been matched by the ability of mobile networks to deliver high-quality video streams consistently to such nomadic users. In this work, we propose CMT-NEMO, a novel concurrent multipath transfer scheme for the delivery of scalable video content to users in multihomed mobile networks such as those expected to be found in public transport scenarios. Recent research in this context has shown that the single largest limiting factor for perceived video quality is the overhead introduced by path switching operations in multihomed mobile networks. CMT-NEMO eliminates the need for path switching and, by removing the associated path switching latency, provides a substantial performance improvement across a wide range of bandwidths and test sequences. An average Y-PSNR improvement of 5.9 dB is achieved when compared with previously proposed schemes. [ABSTRACT FROM AUTHOR]

This paper describes the design and implementation of a multimedia home gateway for threescreen television (3STV) service. The proposed in-home wireless network uses scalable video coding (SVC) and unequal error protection with Raptor forward error correction (FEC) for maximizing the quality of experience (QoE) over the variable-bandwidth, error-prone wireless network. The gateway incorporates (a) dynamic SVC layerswitching, which enables the server to perform selecting appropriate layers from SVC bitstreams, (b) adaptive Raptor FEC, which controls the overhead of Raptor FEC according to packet loss rate (PLR), (c) an efficient combination of (a) and (b), and (d) slice group-based selective streaming in the overall gateway architecture. The paper explains the home gateway architecture as well as experiments for performance evaluation as compared to that of traditional SVC streaming. In the experiments conducted, gains in video quality vary from 2 to 5dB in peak signal-to-noise ratio (PSNR), with corresponding subjective improvements. Overall reductions of bit rate at the input to the home gateway vary from 28% to 36%1. [ABSTRACT FROM AUTHOR]

H.264/SVC has been widely adopted to smart CE devices for network-adaptive video transmission. However, current H.264/SVC does not support sufficiently high subjective QoS (Quality of Service) because its scalability methods provide only coarse-grained network adaptivity. To address this problem, we propose a Scalable ROI (SROI) algorithm that applies the ROI (Region of Interests) concept to SVC (Scalable Video Codec). While existing methods use a fixed size of enhancement layers, our method utilizes only ROI area as an enhancement layer so that it can improve subjective QoS with low transmission overhead. Through some experiments, we show that our method can increase PSNR (Peak Signal-to-Noise Ratio) by 4~5 dB in ROI areas. [ABSTRACT FROM PUBLISHER]

In this paper, the implementation of a DSP-based video decoder compliant with the H.264/SVC standard (14496-10 Annex G) is presented. A PC-based decoder implementation has been ported to a commercial DSP. Performance optimizations have been carried out improving the initial version performance about 40% and reaching real time for CIF sequences. Moreover, the performance has been characterized using H.264/SVC sequences with different kinds of scalabilities and different bitrates. This decoder will be the core of a multimedia terminal that will trade off energy against quality of experience. [ABSTRACT FROM AUTHOR]

This paper presents a low-cost highperformance H.264/AVC SVC decoder with multi-symbol prediction context-based adaptive variable length coding (CAVLC) for advanced T-DMB receiver. Proposed multisymbol prediction CAVLC mainly consists of a simple arithmetic operation unit with reduced look-up tables and a leading zero detector. We also propose a multi-symbol run_before decoder and it decodes more than 2.5 symbols in a cycle. Gate count of a H.264/AVC SVC decoder is about 1,300K gates when synthesized with 0.18um CMOS process and it can be operated at 120MHz clock frequency. For the verification of a H.264/AVC SVC decoder chip, prototype mobile movie player systems have been implemented using a 7 inch LCD and USB controller1. [ABSTRACT FROM AUTHOR]

Consumer demand for portable wireless devices such as smartphones or tablets capable of receiving high quality video content has risen sharply in recent years. This paper considers the real-time delivery of streamed H.264 Scalable Video Coding (SVC) content to users of such devices within mobile networks (e.g. situations where they are part of a group moving together on a bus or a train). We propose a novel scheme for the multipath delivery of H.264 SVC content to users in multihomed mobile networks .By implementing our scheme on a realistic testbed, we show that it offers a significant improvement in received video quality over previously proposed alternative schemes1. [ABSTRACT FROM AUTHOR]