Search

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]

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 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]

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]