We consider the problem of high definition video transmission in a heterogeneous wireless network from a video server to a multihomed client. On one hand, a single wireless network is limited in transmission performance (e.g., available bandwidth and link delay); On the other hand, the high definition video streaming is characterized by high transmission rate and large-size video frames. Thus, the end-to-end video frame delay becomes a severely challenging problem which is critical for real-time video applications. In this paper, we propose a novel scheduling approach named SFL, which deliberately splits large-size video frames into sub-frames and dispatches each of them onto a different wireless network to the multihomed client. This approach is able to improve the frame-level delay performance for enhancing video quality. We formulate a optimization problem of video streaming allocation for minimizing the end-to-end delay based on the network calculus and derive its solution with the water filling algorithm. We evaluate the performance of the proposed SFL through Exata emulations using real-time H.264 video streaming. Emulation results show that SFL outperforms existing frame level scheduling approaches in improving frame-level delay as well as in enhancing video quality in terms of PSNR (Peak Signal-to-Noise Ratio).
['Jiyan Wu', 'Jingqi Yang', 'Xiaokun Wu', 'Junliang Chen']
A low latency scheduling approach for high definition video streaming over heterogeneous wireless networks