Exploiting layer and spatial correlations to enhance SVC and tile based 360-degree video streaming

Streaming 360-degree videos over today’s Internet is challenging due to its high bandwidth and low Motion-to-Photon latency requirements. Viewport adaptive streaming is a promising technique to cope with these challenges by allocating more bitrates to a user’s constrained field of view and streaming appropriate representations based on the user’s estimated throughput and fixation point. A typical dynamic adaptive streaming system uses a Media Presentation Description (MPD) file to describe the sustainable bitrates of a period for different quality representations. However, video bitrates vary significantly along the temporal dimension for Variable Bitrate (VBR) videos. In addition to the throughput overestimate/underestimate problem, video bitrate overestimate/underestimate also affects the efficiency of Adaptive Bitrate (ABR) algorithms.