Navigation-aware adaptive streaming strategies for omnidirectional video

Virtual reality (VR) applications target high-quality and zero-latency scene navigation to provide users with a full-immersion sensation within a scene. From a network perspective, this requires transmission of the omnidirectional content in its entirety, at a high resolution, which is not always feasible in bandwidth-limited networks. In this work, we propose an optimal transmission strategy for virtual reality applications able to fulfill the bandwidth requirements, while optimizing the end-user quality experienced in the navigation. In further detail, we consider a tile-based coded content for adaptive streaming systems, and we propose a navigation-aware transmission strategy at the clientside (i.e., adaptation logic), which is able to optimize the rate at which each tile is downloaded. First, we introduce the viewport- quality as metric that reflects the quality of any portion of the sphere displayed by the end-user. Then, we cast the tile-rate optimization as an integer linear programming problem and show that the proposed solution achieves substantial quality gains when compared to state-of-the-art adaptation logic methods.