A network-adaptive SVC Streaming Architecture

For video streaming, we must consider terminal and network characteristics. The scalable video coding (SVC) can represent video bitstreams in different scalable layers for flexible adaptation to terminal and network characteristics. The SVC can allow for extraction of appropriate partial bitstreams to meet specific target bitrates and spatial resolutions from an SVC bitstream with several spatial, temporal and quality scalability layers. Moreover, the extraction process is fast, so it is possible to extract the partial video streams online to cope with the delivery networks with changing characteristics such as bandwidth etc. With all the advantages of SVC, we design and implement a network-adaptive SVC streaming system to extract partial SVC bitstreams to meet the required target bitrates and spatial resolutions. We present the implementation of our SVC streaming system with experimental results.

1. Introduction

In order to deliver video streams over the networks with different bandwidth to a variety of terminals, the conventional streaming systems usually prepare multiple encoded versions of each video to cope with the different characteristics of target terminals and delivery networks. Maintaining such multiple versions of videos streams at the transmission sides usually requires large storage capacity and management resources. To avoid the pitfalls of the conventional methods, The JVT (Joint Video Team) by ISO/IEC MPEG and ITU – T VCEG is currently standardizing Scalable Video Coding (SVC) with the aim at providing a flexible representation of compressed video bitstreams so that the compressed bitstreams can correspond to the changes in delivery and consumption environments [2]. In SVC, the bitstream is represented in salable ways with spatial layer, temporal layer and quality layer. A full SVC bitstreams can be extracted at all layers to form partial bitstreams in fine-granular levels with fast extraction process.