SVC adaptive layer switching algorithms over the WiMAX network for Taiwan High Speed Rail

For the sake of satisfying the requirement of different receivers and adapting the network condition, a new video coding scheme appears and is called Scalable Video Coding (SVC). Different from traditional coding scheme i.e. H.264, encoding once by using SVC encoder can generate one bitstream with different resolutions as well as frame rate, and the bitstream can be corresponded with the requirement of different receivers. In this paper, we propose two adaptive SVC layer switching algorithms for dedicated Worldwide Interoperability for Microwave Access (WiMAX) network of Taiwan High Speed Rail (THSR). The adaptive layer switching algorithms are based on network condition to adjust to delivering video data. For the first algorithm, we record the Received Signal Strength Indicator (RSSI) trace at the high speed moving environment of THSR in advance, and measure the available network bandwidth with RSSI trace. Then, Streaming Server can deliver the corresponding SVC layer data by measured network bandwidth. As to the second algorithm, Streaming Server estimates network available bandwidth from static information such as packet loss rate sent by Streaming Client. Streaming Server can select and deliver SVC layer data which are adapted to estimated network bandwidth. Our streaming system is an adaptive streaming system because video layer switching adapts to different network conditions.