Impact of end-user playout buffer dynamics on HTTP progressive video QoE in wireless networks

We study the impact of the dynamics of the end-user playout buffer on the quality of experience (QoE) of the HTTP progressive video over wireless networks in this paper, especially the impact of the block size and the finite video length on the playback interruption during wireless video watching. The playout buffer at the end-user is formulated as a G/D/1 queue with arbitrary packet arrival and deterministic playback. An analytical framework is presented to investigate the impact of the playout buffer dynamics on the wireless HTTP progressive video QoE by analyzing the transient queue length of the buffer with the diffusion approximation method. The close-form expressions for the user-perceived video quality, in terms of the buffering delay, the playback duration and the playback interruption probability, are obtained. The results show that both the buffering delay and the interruption probability decrease as the average arrival rate increases for a given buffer threshold. The higher the video quality, the greater the impact of the dynamics of the arrival process on the buffering delay and interruption probability is. Moreover, a larger playback threshold leads to a more rapidly decreasing of the interruption probability along with the increase of the average packet arrival rate. The proposed analytical framework is validated by simulations.