Investigation On Multi-screen Interactive System Of Public Display Based On Android Platform

Aimed at the existing problems of public display control system:control procedures are cumbersome,low flexibility,can not play resources selectively and can not update content in real time.In this paper,we design a multi-screen interactive system of public display based on Android platform.The system combines the Wi-Fi Display technology and DLNA standard,through the design of Wi-Fi Display module,DLNA module,and on this basis,design the Wi-Fi Display and DLNA integrated module,realize the multi-screen interaction between the mobile intelligent terminal and the public display,so as to achieve the purposes of mobile intelligent terminal control public display in real time and edit rapidly.And it is a new control way for public display that not only enhances the overall performance of public display control the system,but also operate conveniently for users and has obvious theoretical and practical significance for the research and market application of public display.The system design of the three modules and methods include:(1)The design of Wi-Fi Display module:after use Wi-Fi Direct technology to search and match equipment,connect the mobile intelligent terminal with the public display,the mobile intelligent terminal intercept the screen data stream and audio stream in real time.Then,the data stream is compressed through H.264 also encapsulated by RTP/RTCP protocol and send to the public display,which is decoded by the public display to reduce screen data.Next,the mobile intelligent terminal based on Wi-Fi Display is used to mirror the public display.Finally,achieves the mirror control of the mobile intelligent terminal and public display based on Wi-Fi Display.(2)The design of DLNA module:Set the mobile smart terminal as digital media controller(DMC)and digital media server(DMS)while setting the public display as a digital media renderer(DMR).Firstly,the DMS provides services that such as browsing multimedia content,multimedia content format,URI and so on;and then,DMC through the SOAP protocol to coordinate that DMS transfers media streams to DMR and sends a control command message to the DMR for playback control.Finally,achieves the content stream push and play control based on DLNA standard.(3)The design of Wi-Fi Display and DLNA integrated module:On the basis of completing the design of Wi-Fi Display module and DLNA module,through WfdThead,DlnaThead to call the background services of DLNA and Wi-Fi Display to achvice the interaction with UI thread.And set the definition of the content as the benchmark to complete the switch of control mode.Finally,it integrates the Wi-Fi Display screen mirroring faction and the DLNA content stream push function in the system,which enhances the control flexibility and convenience of the whole system.The test results show that:compared with the typical control system of public display,multi-screen interactive system of public display based on Android platform can update the the contents of public display in real time.Also,the mirror control and content push of mobile intelligent terminal to public display are realized.At the same time,the wireless control distance is fifteen meters,the setting time is one-sixth of typical control system and the control method is out of the way of the past.