The Design And Implementation Of Smart-TV-based Network Projection System

With the development of mobile Internet media and the technical innovation of intelligent devices,smart TVs have become the center of family entertainment.People have various ways to watch videos,listen to musics and play games,e.g.using smartphones and using PCs.However,the smartphones usually have small screens and quite simple sound playing units.PCs usually have fixed positions and they need messy cables to connect different components.Neither smartphones nor PCs can provide the best watching and playing experience.In view of this,this thesis designs and implements a smart TV based network projection system.This system can not only project the multimedias in PCs or smartphones into the smart TVs,but also project the games running on PCs into the smart TVs.This system can utilize the advantage of different devices and make them concentrate on a single function.The system can be divided into three subsystems,they are multimedia projection subsystem,game projection subsystem and fundamental service subsystem.The fundamental service subsystem is developed to provide the command of discovery,authentication,command interaction and so on.The multimedia projection subsystem contains the multimedia player component,the proprietary projection component and the general projection component.The proprietary projection component can receive the projection of user's video,audio and photo by calling the multimedia player module,the discovery module,the authentication module and the command interaction module.Users can project videos,musics and pictures into it.The general projection component is the implementation of the DLNA protocal on TVs.It can not only receive the projection of offline multimedia resources,but also receive the projection of online multimedia resources.Compared with the proprietary projection component,the general projection component have a better compatibility with the third party software,but it will consume much more time in the device discovery phase.Therefore,they achieve the functional complementarity.The game projection subsystem need cooperate with the Geforce Experience software on PC.First,the Geforce Experience can capture and encode the graphics of games runnig on PC.Then,the game projection subsystem can receive the bitstream of the encoded graphics and decode it.Finally,the game projection subsystem renders the graphics into the screen of the smart TV.This thesis firstly analyzes the need of projecting multimedias of PC and smartphones onto the smart TVs in the era of mobile Internet.Then,the key technologies and their principles used in this system are introduced.Next,this thesis makes a demand analysis according to the usage scenarios,which helps to define the required functions of the two subsystems and the requirements of these different funcitions.In the phase of designing and implementation,this thesis builds the framework of the whole system firstly.Then,the roles of different components and their relationships are defined.In addition,the working processes of different components are provided.Finally,the implementation of different components are introduced.In the phase of testing,this thesis not only make functional tests on different components,but also tests the performance of this system.Experiments on the sixth chapter show that all of the functions of this system can work well,and the design goals have been achieved.