An adaptive streaming method of 360 videos over HTTP/2 protocol
Nowadays, 360-degree video has become an important component of virtual reality (VR) technology. Unfortunately, this state-of-the-art content type requires a huge bandwidth from a server to a client. In order to solve the bandwidth problem in streaming VR videos over HTTP/2, a dynamic adaptation method is crucial. In this paper, we propose a novel adaptive streaming method based on tiled streaming. By using H.265 standard, a video at the server is divided into spatial tiles, each of which is subdivided into multiple temporal segments. In order to support adaptive streaming method from client, each tile is also encoded into different versions. The priority of tiles is defined based on the user's viewport. Then, the priority feature of HTTP/2 is used to request the server to push the tiles of higher priority first. This ensures that the visible tiles will arrive at the client and be decoded first. Besides, in the case of bandwidth fluctuation, we use the stream termination feature to cancel pushing the tiles that would arrive at the client after their playout deadlines.