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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]

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]