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In mobile systems, it is essential to limit the amount of energy consumption if the energy budget is low. This paper proposes a new scheme that makes use of quality scalability in scalable video coding (SVC) to limit energy usage by taking quality-of-experience (QoE) factors into account. To address the tradeoff between QoE and energy consumption, a new dynamic voltage and frequency scaling (DVFS) technique is proposed in which the fidelity level of each video segment is dynamically selected. The proposed scheme estimates the amount of energy consumption based on the analysis of the computational requirements to decode previous frames, and chooses the fidelity level to achieve the best video quality metric (VQM) value within a given energy budget. It was implemented on a recent commercial smartphone in which a new interface is provided for users to control the energy usage based on video quality. Real measurements show that it makes effective use of the remaining battery while maximizing QoE1. [ABSTRACT FROM PUBLISHER]

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]

Transcoding of H.264/AVC bitstreams is frequently used for adapting video streams to varying network conditions or different end-user device characteristics. Transcoding requires a relatively high complexity (and thus high operational cost) for each adaptation operation, and possibly reduces the video quality. In comparison, transcoding the input bitstream to SVC requires only one adaptation step. Afterwards, the resulting SVC bitstream can be adapted instantly. To reduce the H.264/AVC-to-SVC transcoding complexity, a transcoding architecture which combines existing open-loop transcoding techniques with optimized closed-loop transcoding is proposed. Furthermore, this approach allows to scale the complexity of the system. Doing so, compared with a cascaded decoder-encoder only 8.48% of the complexity is required for the highest complexity, while a high rate-distortion efficiency is maintained and a high degree of scalability is guaranteed. When only limited resources are available, the transcoding complexity can be scaled such that over 99% of the complexity is reduced compared to a cascaded decoder-encoder. [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]

This paper presents an efficient VLSI architecture of in-loop deblocking filter (ILF) with high efficiency data access system for supporting multiple video coding standards including H.264 BP/MP/HP, SVC, MVC, AVS, and VC-1. Advanced standards, such as H.264 MP/HP, SVC, and MVC, adopt Macro Block Adaptive Frame Field (MBAFF) to enhance coding efficiency which results in the performance bottleneck of deblocking filter due to complex data access requirement. This design challenge has not been discussed in previous works according to our best knowledge. Therefore, we develop a Prediction Data Management (PDM) to manage the input prediction data order of deblocking filter for different coding types (like frame/field) and multiple standards. We also design an extended output frame buffer module to solve the system bus architecture restriction (like 1K boundary and burst length) and achieve high efficiency data access by using MB-based scan order. By using these techniques, we can solve the data accessing design challenge and reduce 67% bus latency. After being implemented by using 90 nm CMOS technology, the proposed work can achieve real-time performance requirement of QFHD (3840?2160@30fps) when operated at 156MHz at the cost of 50.6K gates and 2.4K bytes local memory. The maximum operating frequency of the proposed design, i.e. 370MHz, is higher than the required real-time operating frequency so that voltage scaling may be adopted to reduce power consumption. [ABSTRACT FROM PUBLISHER]

This paper introduces a video coding scheme called Realistic Multi-view Scalable Video Coding (RMSVC), which is designed for the future ubiquitous environment. Unlike most video coding schemes that support only 2D or 3D displays, the proposed RMSVC coding scheme can support realistic services, such as 3D television, stereoscopic display, variablesized 2D displays, etc., and can efficiently deliver realistic video data in the ubiquitous environment that mixes various terminals and networks. In this paper, the proposed RMSVC scheme is designed and implemented by integrating the structures of Multi-view Video Coding (MVC) and Scalable Video Coding (SVC) schemes, and then shows in a simulation the possibility of realizing RMSVC. In addition, this paper proposes a layered prediction structure for the proposed RMSVC scheme. The simulation results show that the proposed structure remarkably improves the performance of random access while maintaining very similar coding efficiency. [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]

Spatial and temporal scalability in Scalable Video Coding (SVC) compression enables a video encoder to generate bit streams efficiently for various resolutions and frame rates. However, doing this requires more complex computations and greater memory bandwidth than H.264/AVC compression. In this paper, the performance and memory bandwidth for a SVC hardware encoder with three spatial and temporal layers are analyzed. Based on the analysis, a novel method is proposed for the source and interlayer data load. Experimental results show that the memory bandwidth is reduced by 77%. Furthermore, the memory access latency of the source data for the base layer is reduced by creating a data load for the base layer overlap with the execution of the enhancement layer. To satisfy the latency requirement, a mode pre-decision algorithm for a hardware SVC encoder is proposed. It reduces the computation of the fractional motion estimation (FME) and the inter-layer residual prediction by 80%. Simulation results show that the proposed methods decrease the BD-PSNR by 0.05 dB and increase the BD-BR by 1.64%, an amount that can be considered negligible in terms of degradation, while an encoding speed of 30 fps for Full HD (1920?1080) videos is achieved at an operating clock frequency of less than 200 MHz.1 [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]

This paper presents a strategy that efficiently allocates the limited resource and still maintains the coding performance for the spatial scalability of H.264/SVC. An integrated computation-scalable algorithm is proposed on the basis of priority-based mode decision (PBMD) and activitybased motion estimation (ABME). The rate-distortion cost (RD-cost) of base layer is utilized as the priority to decide the mode in the enhancement layer, and the motion vector difference (MVD) in the base layer is employed to determine the search range as well. Through the proposed approach, computation complexity of the enhancement layer could be reduced efficiently and well allocated. A fast algorithm with early termination mechanism is also proposed in this paper. Experimental results demonstrate that the various ratedistortion and time-saving performances with computation scalability are realized. [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]

Scalable video coding is an important mechanism to provide several types of end-user devices with different versions of the same encoded bitstream. However, scalable video encoding remains a computationally expensive operation. To decrease the complexity we propose generic techniques. These techniques are generic in a sense that they can be combined with existing fast mode decision methods and optimizations. We show that extending such an existing fast mode decision technique yields an average complexity reduction of 87.27%, while only an additional 0.74% of bit rate increase and a decrease of 0.11dB in PSNR is required, compared to the original fast mode decision method. [ABSTRACT FROM AUTHOR]

This paper presents a novel algorithm designed to efficiently adapt scalable video using MPEG-21. The algorithm is able to take the optimal decision among all possible video adaptations. It takes into account information about network, user terminal and user preferences. This information is gathered together by means of MPEG-21 DIA descriptors. The decision on the optimal adaptation is achieved through the application of the Viterbi algorithm. The results prove that the presented decision-taking engine offers an optimal and efficient solution for personalized scalable video adaptation in heterogeneous environments. [ABSTRACT FROM AUTHOR]

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]

Scalable Video Coding is an H.264/AVC scalable extension that is used to provide various network-friendly scalability using a single bit stream. In SVC, the newly adapted predictive coding techniques can achieve high encoding efficiency, but they increase the computational complexity. To reduce the computational complexity, we present a fast mode decision algorithm based on the block complexity function considering the degree of correlation between base layer and enhancement layer. The simulation results show that the encoding time of the proposed fast mode decision algorithm for the combined scalability is about 54.72% compared with normal method although the loss of visual quality is negligible. [ABSTRACT FROM PUBLISHER]

Video contents needs to be compressed in order to reduce the resources required for storage and network transmission. It is desirable that the encoded bitstreams are adaptable to the varying characteristics of consumer electronics devices and heterogeneous networks. Scalable Video Coding provides temporal, spatial and quality scalability by organizing the encoded bitstream into layers. Since the majority of the produced video content is currently encoded using H.264/AVC, it will be necessary to implement techniques for converting from single-layer H.264/AVC to scalable bitstreams. In this paper, a technique for transcoding from H.264/AVC-to-SVC with temporal scalability in Baseline Profile is discussed. Applying the presented approach, a reduction of 64% of the coding complexity is achieved while maintaining the coding efficiency. [ABSTRACT FROM PUBLISHER]

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]

In this paper, Reduced Resolution Depth Compression (RRDC) is proposed for Scalable Video Coding (SVC) to improve the 3D video rate distortion performance. RRDC is applied by using Down-Sampling and Up-Sampling (DSUS) of the depth data of the stereoscopic 3D video. The depth data is down-sampled before SVC encoding and upsampled after SVC decoding operation. The proposed DSUS method reduces the overall bit rates and consequently: 1) improves SVC rate distortion for 3D video, particularly at lower bit rates in error free channels; and 2) improves 3D SVC performance for 3D transmission in error prone channels. The objective quality evaluation of the stereoscopic 3D video yields higher PSNR values at low bit rates for SVCDSUS compared to the original SVC (SVC-Org), which makes it advantageous in terms of reduced storage and bandwidth requirements. Moreover, the subjective quality evaluation of the stereoscopic 3D video further confirmed that the perceived stereoscopic 3D video quality of the SVC-DSUS is very similar to the stereoscopic 3D video of the SVC-Org by up to 98.2%. [ABSTRACT FROM PUBLISHER]