Android-based Real-time Video Monitoring Client Design And Implementation

With the rapid development of technologies of network and smart phone, the number of smart deviceusers has been growing and more and more affairs have also been dealt on the little device. Therefore,video monitoring has become increasingly important. The traditional video monitoring has already beenapplied in many areas such as safe city construction, electric and hydraulic observation, forest fireprevention and automated production. Now people pay more attention on flexibility and the traditionaltechnologies which use PC to monitor cannot meet demands. Under this background, this thesis proposed adesign and implement of a real-time video monitoring based on Android smart phones in order to realisethe real-time monitoring. This scheme has a very high real and commercial values.The scheme proposes a layer-divided plan based on FFmpeg. The plan divides client into three layers,namely data reciveing layer, data decoding layer and UI display layer. The data receiving sets up the linkwith remote server in order to receive RTP data packages. The data decoding layer calls FFmpeg decodinglibrary to decode the packages. The UI display layer calls SDL to decode frames and draw the picture.Android media library opencore can only be used to play videos in3pg and mp4. However, FFmpegexpands opencore and let opencore to play more formats.This thesis analyzes reltated video monitoring technologies and protocols such as RTSP, RTP andRTCP. Then the thesis introduces the mainstreaming video encoding technology H.26. The thesis choosesAndroid as developing platform because of its openness and a large user number after compared with othersmart phone operating systems. FFmpeg is an open source media solution for PC and its codes are Clanguage. Android smart phone’s memory is small and its apps are developed with java language. Thereforethe thesis uses Android NDK to realize the cut and transplant of FFmpeg. The thesis contains how to useJNI to call c codes with java codes and how to call dynamic library when FFmpeg is compiled so as todecode the data packages. The thesis also contains how to use SDL to complete picture drawing and how touse layout files to improve the interface. After completing client, tests have been done. The results showthat the software can play monitoring videos and local videos.