Research And Development Of Wireless Audio And Video Teaching Terminal Based On Android System

As we all know, intelligent mobile terminals have become necessity in people’s daily life and study,such as mobile phones, tablet PCs and others.They have create many intelligent applications replacing man’s labor and providing convenience for life and study,as same as computers.The traditional teaching mode has been changed and improved with the development of multimedia technology.But there is still no mature technology to design the teaching mode by using the mobile intelligent terminal.In view of the above situation,this study will design teaching application based on wireless audio and video technology on the mobile intelligent terminal platform.This study has realized the function of teaching and learning through audio and video interaction for teachers and students,taking Android as the development environment which had been launched by Google with the SDK for Android and wireless local area network technology.This study uses the advanced mobile intelligent terminal as the hardware,with the underlying environment based on the mature ARM processor equipped with Linux system,and it chooses Android as system which is open source and increasingly sophisticated.The hardware integrates a high performance camera module and audio module.It has driven the wireless network card by hardware which can be connected to the network directly.The LCD touch screen that has high resolution can meet the needs of video system.The software takes Android as the basic development framework,using C/C++ to realize the function of the underlying module and Java to develop the application. In terms of key technologies,this study implements the video coding and decoding based on H.264,the audio coding and decoding based on AAC and realizes the audio and video synchronization mechanism by calling the local FFmpeg dynamic library using JNI technology which uses the FFmpeg audio and video processing system as the research foundation. This study realizes the control to the network transmission of audio and video using the RTP/RTCP streaming media transmission protocol based on UDP which uses the wireless network technology as the data transmission channel based on WiFi.This study collects teaching audio and video information in real time by the hardware device with built-in camera and sound system,and then realizes the compression coding by the audio and video processing technology based on FFmpeg through program design. The teaching stream media data is sent to the student receiving end from the local server through the RTP/RTCP real time transmission protocol. Then the audio and video information can be restored by decoding and processing the streaming media data synchronously completing the function of the wireless teaching.The focus of this design is the realization of the core function of mobile teaching terminal: audio and video transmission by wireless WiFi based on Android in real time.This design makes module division and in-depth study on the object.Not only has it meet the design requirements on the application layer by Java programming,but also it has analyzed and discussed the principle of the underlying C/C++ implementation.Finally,this study matches the key technology to the design of the teaching terminal functions, and then carries on the software test analysis,achieving the goal of this study.