Research Of Wireless Video Multicast And Interaction Terminal Based On Wi-Fi

With the limitation of network bandwidth nowadays, traditional media need to playonly after the task has been complete download. In order to solve this problem, streamingmedia technology emerged which can let the video broadcast while it is downloading. In theapplication of single point to multipoint of IP network, multicast technology has moreadvantages, which can make the media sever send a continuous data stream to multipleclients at the same time without delay. In addition, this technology does not produce abroadcast storm and greatly improve the utilization rate of network. Embedded system is ahotspot research currently, which has the characters of low power consumption, highintegration, strongly specificity, smart, portable, etc.Nowadays, with the rapid development of wireless networks, among many wirelessstandards of which won the favour of people with the advantages of its low constructioncosts, high transmission rate and the far distance transmission. Wi-Fi as the currentmainstream wireless access standards, with its strong scalability and high mobility, isgetting more and more attention.Therefore, this paper put together the H.264video compression standard, streamingmedia transmission technology and Wi-Fi communication module to design wireless LANvideo multicast and interactive terminals based on Wi-Fi. For the application background ofmultimedia teaching, this system was designed and implemented four main functions: theroll call, video multicast, video interaction, video storage and playback. With the limitationof space, just concretely introduce two main functions: video multicast and video interaction.This paper introduced the system implementation from two aspects of hardware design andsoftware design, the hardware design mainly involved the selection of embedded ARMprocessor and cameras, wireless CARDS, LCD, hardware module selection; the softwaredesign mainly included the construction of the system development environment, hardwaremodule driver under Linux system, the transplantation of kernel, function development ofapplicant software and Qt4.7user interface design. Aiming at the implementation of mainfunctions of the system, the paper emphasized on the statement of cmos camera OV9650video data acquisition method, the working principle and realization of multiple formatcodec MFC H.264hardware encoding and decoding, the realization and announcements of the H.264data streaming media transmission, and the transportation of Qt4.7browser.This article also gave a depth narration and analysis about the problem the author met in thepractice and the method how to solve it, finally tested the function and performance of thesystem, made a summary and put forward the improvement opinion.