Tile-Based Joint Caching and Delivery of 360° Videos in Heterogeneous Networks

Abstract

The recent surge of applications involving the use of 360 o video challenges mobile networks infrastructure, as 360 o video files are of significant size, and current delivery and edge caching architectures are unable to guarantee their timely delivery. In this paper, we investigate the problem of joint collaborative content-aware caching and delivery of 360 o videos in a video on demand setting. The proposed scheme takes advantage of 360 o video encoding in multiple tiles and layers to make fine-grained decisions regarding which tiles to cache in each Small Base Station (SBS), and where to deliver them from to the end users, as users may reside in the coverage area of multiple SBSs. This permits to cache the most popular tiles in the SBSs, while the remaining tiles may be obtained through the backhaul. In addition, we explicitly consider the time delivery constraints to ensure continuous video playback. To reduce the computational complexity of the optimization problem, we simplify it by introducing a fairness constraint. This allows us to split the original problem into subproblems corresponding to Groups of Pictures (GOP). Each of the subproblems is then solved with the method of Lagrange partial relaxation. Finally, we evaluate the performance of the proposed method for various system parameters and compare it with schemes that do not consider 360 o video encoding into multiple tiles and quality layers, as well as with two variants of the proposed method: one that considers layered encoding and SBSs collaboration and another that uses tiles encoding but with no SBSs collaboration. The results showcase the benefits coming from caching and delivery decisions on per tile basis and the importance of exploiting SBSs collaboration.Index Terms-Collaborative caching, 360 o video, tile encoding, layered video, distortion optimization.

Research on Fast Compensation Algorithm for Interframe Motion of Multimedia Video Based on Manhattan Distance

“…erefore, video interframe motion compensation plays an important role in many technologies included in video processing [4].…”

Machine Learning for Multimedia Communications

“…This content preparation and delivery may introduce prohibitive delays, as the playback delays are very short for live streaming of 360-degree video. An alternative to DASH-like video streaming is the use of scalable video coding (SVC) [ 124 , 125 , 126 ]. In SVC-based systems, the video is encoded multiple quality layers (a base layer and possibly multiple enhancement layers).…”

Video Caching, Analytics, and Delivery at the Wireless Edge: A Survey and Future Directions

“…Next, collaborative caching and delivery has also been studied in the context of 360°videos. Maniotis et al [205] study a collaborative approach with SVC encoding of 360°v ideos to decide which tiles and layers of videos are cached in each SBS and which route to deliver them to interested UEs. Decoupling the problem into caching and routing optimizations, Lagrange partial relaxation method is applied to solve the problem.…”

“…In the context of 360°videos, properties of the field-of-view or viewport of the user are used to cache or proactively send high quality frames, such that the users' QoE is improved. Maniotis et al [205] consider an optimal caching scheme that uses layered and tile-based encoding of 360°videos. Specifically, each tile is encoded into layers of different qualities.…”