Design And Realization Of Audio And Video Synchronous Surveillance System

With the development of large scale integrated circuits,technology of hardware in embedded-system has also been rapidly improved.Embedded video surveillance system combined with Internet technology,wireless communication technology,audio and video codec technology as well as smart algorithm can provide in addition to pictures,such as voice,target detection,tracking a full range of information,it has become a new application direction in the field of security now.This thesis firstly summarizes the background and significance of the video surveillance system and analyzes the current research status and development trends of video surveillance system.In this context,This thesis embarks from the practical application of design has realized a wireless audio and video synchronous surveillance system based on ARM and Linux.Surveillance system consists of server and client components,server-side implementation of audio and video data collection,coding,and synchronous transmission,and client-side achieve synchronization of audio and video monitoring,the system can fully meet the people's demand for video surveillance.This design first install the CentOS operating system on the virtual machine VMware Workstation to complete cross-compile environment set up.Design and realization of surveillance system server-side in ARM development board,including bootloader,the Linux kernel and a root file system configurations and transplantation.Transplantation and configuration of cameras,microphones,wireless LAN driver,Set up RTMP(Real Time Messaging Protocol)server.On this basis,through V4L2(Video for Linux two)interface under Linux for video data acquisition and use FFmpeg complete H.264 compression of video data.Through the ALSA(Advanced Linux Sound Architecture)interface under Linux for audio data acquisition and use FFmpeg complete AAC(Advanced Audio Coding)compression of audio data,the server push out the compression of audio and video data after an RTMP packet.Last PC,mobile phone and other client use FFmpeg and VLC play audio and video.In addition to audio and video synchronous surveillance,this design also uses open source Motion algorithm to achieve a dynamic image monitoring.Tests showed that the system design is reasonable,stable operation,at the same time,it has the advantages of low complexity,flexible networking,easy expansion and high cost performance.Effectively meets the growing needs of the video surveillance system,it can be extended to multiple applications such as safe city,safe school smart city,smart home.