A Joint Asymmetric Graphics Rendering and Video Encoding Approach for Optimizing Cloud Mobile 3D Display Gaming User Experience

摘要

With the development and deployment of ubiquitous wireless network together with the growing popularity of mobile auto-stereoscopic 3D displays, more and more applications have been developed to enable rich 3D mobile multimedia experiences, including 3D display gaming. Simultaneously, with the emergence of cloud computing, more mobile applications are being developed to take advantage of the elastic cloud resources. In this paper, we explore the possibility of developing Cloud Mobile 3D Display Gaming, where the 3D video rendering and encoding are performed on cloud servers, with the resulting 3D video streamed to mobile devices with 3D displays through wireless network. However, with the significantly higher bitrate requirement for 3D videos, ensuring user experience may be a challenge considering the bandwidth constraints of mobile networks. In order to address this challenge, different techniques have been proposed including asymmetric graphics rendering and asymmetric video encoding. In this paper, for the first time, we propose a joint asymmetric graphics rendering and video encoding approach, where both the encoding quality and rendering richness of left view and right view are asymmetric, to enhance the user experience of the cloud mobile 3D display gaming system. Specifically, we first conduct extensive user studies to develop a user experience model that takes into account both video encoding impairment and graphics rendering impairment. We also develop a model to relate the bitrate of the resulting video with the video encoding settings and graphics rendering settings. Finally we propose an optimization algorithm that can automatically choose the video encoding settings and graphics rendering settings for left view and right view to ensure the best user experience given the network conditions. Experiments conducted using real 4G-LTE network profiles on commercial cloud service demonstrate the improvement in user experience when the proposed optimization a- gorithm is applied.