三维视频带给用户沉浸式的视觉体验，因此受到学术界和工业界的广为关注。然而，目前已有的三维视频在视点切换和网络传输过程中还存在较大问题。已有三维视频的传输研究都是基于传统的UDP/RTP框架。使用DASH进行视频传输具有多码率编码，以及根据网络情况和缓存状况自适应调整视频传输码率和防止视频播放卡顿等优点。目前，国内外基于DASH系统的三维视频交互式传输的研究还是空缺的。本课题将结合三维视频交互式传输和DASH系统的内在特点，研究基于DASH的三维视频交互式传输模型。主要包括三个方面的工作：基于DASH系统多码率编码的特点和交互式传输中DASH客户端视角选择的不确定性，研究DASH服务器中三维视频的最佳表示方法；研究DASH客户端用户视角切换模型和对系统性能的影响；研究三维视频交互式DASH系统中的缓存机制。课题的研究将直接推动三维视频在互联网中的应用。

3-D video enables viewers with immersive vision experience, and hence attracts a lot of attentions both from industry and academia. However, for the current 3-D video format, there are many problems in view switching during video streaming. Most existing 3-D video streaming methods are based on the conventional UDP/RTP protocols. Dynamic Adaptive Video Streaming over HTTP (DASH) has many advantages over UDP/RTP, such as multiple rate choices, video quality adaptation based on the network and buffer conditions, and video smooth playback (avoiding buffer starvation). However, there is little research effort on 3-D interactive video streaming over DASH. In this research project, the characteristics of 3-D interactive streaming and the nature of the DASH system will be jointly exploited, and the DASH-based 3-D interactive video streaming system will be studied. Bearing in mind that video contents are stored in the DASH server with multiple rates, and the uncertainty nature of user viewpoint switching for 3-D interactive video streaming, in this project, we are going to investigate how to store the 3-D video data in the DASH server, how the user viewpoint switching model affects the system design, and how to design the 3-D video buffer mechanism in such a system. The research output of this project will help to foster the Internet 3-D video applications.