Optimized viewport-adaptive 360-degree video streaming

Because of the rapid growth of head-mounted displays and 5G networking deployment,360-degree video has become increasingly popular.To generate the real experience of a virtual environment,360-degree videos require an ultrahigh resolution and frame rate to cover an omnidirectional view.These two prerequisites impose challenges for the transmission bandwidth and storage capacity of 360-degree video streaming.To reduce bandwidth and storage waste while providing a good immersive experience,we propose an optimized viewport-adaptive 360-degree video streaming method using high-efficiency video coding tiling,motion-constrained tile sets and MPEG dynamic adaptive streaming over HTTP spatial relationship description.The paper describes the rigorous design of the optimized system,which can assign different bitrates to different tiles in the viewport.The experimental results show that the proposed streaming system compares favourably with existing methods in terms of bitrate savings and storage capacity reduction.