论文标题
通过利用多播机会的最佳传输多质量瓷砖360 VR视频
Optimal Transmission of Multi-Quality Tiled 360 VR Video by Exploiting Multicast Opportunities
论文作者
论文摘要
在本文中，我们想调查多播机会对有效传输360 VR视频的基本影响，以在每个用户进行转换的情况下向多个用户传输。我们建立了一个新颖的数学模型，该模型反映了案例中多播机会对平均传输能量的影响，并在用户转码的情况下反映了转码的能量，并促进了对启用转码的多播机会的最佳利用。在没有用户转编码的情况下，我们优化了传输资源分配，以利用自然多播机会来最大程度地减少平均传输能量。问题是非convex。我们将其转换为等效凸问题，并使用标准凸优化技术获得最佳解决方案。在用户转编码的情况下，我们优化了传输资源分配和传输质量级别的选择，以最大程度地减少平均传输能量的加权总和，并通过利用自然和启用了启用的启用的自然和转码的多播机会来最大程度地减少转码。这个问题是一个具有挑战性的混合离散连续优化问题。我们将其转换为凸（DC）编程问题的差异，并使用DC算法获得次优的解决方案。最后，数值结果证明了在用户转码方面有效利用启用转码的多播机会的重要性。
In this paper, we would like to investigate fundamental impacts of multicast opportunities on efficient transmission of a 360 VR video to multiple users in the cases with and without transcoding at each user. We establish a novel mathematical model that reflects the impacts of multicast opportunities on the average transmission energy in both cases and the transcoding energy in the case with user transcoding, and facilitates the optimal exploitation of transcoding-enabled multicast opportunities. In the case without user transcoding, we optimize the transmission resource allocation to minimize the average transmission energy by exploiting natural multicast opportunities. The problem is nonconvex. We transform it to an equivalent convex problem and obtain an optimal solution using standard convex optimization techniques. In the case with user transcoding, we optimize the transmission resource allocation and the transmission quality level selection to minimize the weighted sum of the average transmission energy and the transcoding energy by exploiting both natural and transcoding-enabled multicast opportunities. The problem is a challenging mixed discrete-continuous optimization problem. We transform it to a Difference of Convex (DC) programming problem and obtain a suboptimal solution using a DC algorithm. Finally, numerical results demonstrate the importance of effective exploitation of transcoding-enabled multicast opportunities in the case with user transcoding.
