The Research Of Embedded Multimedia Event Recorder

Event recorder is an electronic equipment which can record events of the importantinformation, and has been widely applied in the military, transport, public security, fire control,industiral production supervision and so on many domains.Firstly, this paper combines the recorder industry’s development status and developingtrends，and then puts forward research direction of the recorder. The recorder uses embeddedtechnology, and has good portability. It records according to events happened, thus it savesstorage space because it only records effective information, so it can save the energy ofinvestigators. Because of storage space’s reduction, the hardware cost reduces. The record fileincludes pre-record before alarm and record atfer alarm, so it is comprehensive to restore theoirginal situation.Then, the paper divides the recorder by function modules, and introduces thedevelopment platform of hardware and sotfware. In hardware, the development of eventrecorder is based on embedded hardware platform, whose kernel is Z228high performanceprocessor. For integrated with MPEG-4hardware encoder and decoder, Z228provides highcapability for multimedia process and network transmission. In sotfware, the system isdeveloped in Browser/Server module. The server side uses embedded Linux operate system todevelop application sotfware; the client side uses web pages embedded ActiveX control.The final part of the paper is the highlight of the paper. It compares different softwareimplement pl’ans of the recorders important function modules, and then makes detaileddescirption in its realization. It mainly includes the realization of video compression encode,the realization of pre-record, motion detection algorithm, standard storage of record file，design of ActiveX control, design of communication protocol and so on.The recorder system has reached the predetermined function requirements. It canmonitor the scene in real time. When there are motion detection abnormal events or otherevents, it can record the video data before and atfer the alarm. And the record file can beplayed successfully. The functions can also be extended according to the concrete need.