The Design And Realization Of Full Digitalization Of Video Door Phone System Based On ARM And Linux

As the booming revolution of informationization, Smart Home System has been universally accepted by more and more people. Many devices, such as video intercom, emergency call and long-distance control of home appliances, have been playing very important roles in people's daily life. Traditional video intercom system is based on the analog audio-video signal through dedicated bus (usually RS485) which demands not only large amount of video cables, audio cables and some other cables, but also large amount of work for maintaining. What's more, it is easy for a residential area with a huge consumer capacity to be involved in a busy line for the imitated audio-video system can only transport a single audio-video signal. When it comes to digital video door-phone system, one needs not take such problems into consideration for it can get rid of the limitation of region with a more convenient upgrading process; the quality of audio-video transported by digital audio-video system is much better than the traditional one; it can achieve functional integration, such as family alarm, control of home appliances, remote monitoring and community service; and it can save up the expenditure of engineering by shortening project circle and making the installing and debugging more convenient. Selecting from the issue The Design and Realization of Full Digitalization of Video Door Phone System Based on ARM and Linux, this paper mainly focuses on the implement method of the realization of full digitalization of Video Door Phone System.In research contents, this paper discusses the Computer Architecture of ARM S3C6410 and introduces the internal resource and the relevant interfaces of CPU, and further studies how to construct a framework of embedded Linux system, and how to transplant and compile corresponding device drivers. Based on these soft wares and hard wares, this paper also studies the principles of coder and decoder of both JPEG and goes further about the extraction, transmission and synchronization of Audio-Visual system. Meanwhile, it goes deep into the solution to the problem of audio-intercom's echo and further researches the issue of adaptive signal processing.In discussion content, this paper introduces hardware design and software design of the digitalization of Video Door Phone System. The hardware design includes the selection of CPU and the constitution of the peripheral circuit. The soft ware design analyses the concept and method of constructing the framework of embedded software based on hardware platform. Then based on this hardware platform, the paper expounds the process and method of the gather, transmission and playing of Audio-Video System and mainly analyses how to achieve synchronization and to solve the problem of echo cancellation of the Audio-Video System.