WebTorrent based fine-grained P2P transmission of large-scale WebVR indoor scenes

The latency of transmitting large-scale 1 WebVR scenes over mobile Internet is known as the bottleneck problem. This paper attacks this challenging problem by combining graphics based progressive transmission and networking based P2P transmission together. Different with those pure research DVE (Distributed Virtual Environment)-P2P works built on simulation platform, a novel WebVR-P2P framework is realized based on WebTorrent and WebGL. At server side, huge WebVR scenes are lightweighted by finding all repetitive components and removing redundant ones, that avoids unnecessary transmission. Furthermore, large-scale WebVR indoor scenes are divided into smaller fine-grained subspaces in terms of closeness and visibility to lower networking congestions. These two preprocessing steps are integrated to decrease less bandwidth occupation at utmost. Then, each fine-grained subspace is packaged adaptively in terms of Frustum Fill Ratio (FFR) for smooth and efficient transmission. A new WebTorrent framework is extended to transmit Web3D files and all packaged WebVR subspaces are transferred in the peer-to-peer style. At Web-end, two-thread, one for package transferring and the other for rendering, is employed asynchronously to realize online real time rendering. Finally, WebVR-P2P platform with three layer architecture is implemented based on all above key technologies, a large-scale WebVR Metro scene (about 1GB) is chosen to test for P2P transmission performance in this WebVR-P2P platform, the practical experimenting results are conducted to show the effectiveness and potentiality of our proposed solution.