Research And Implement On A New Type Home Alarm System Based On STM32

With the improvement of people’s living standard, the problem of home security has been concerned by more and more people. This paper firstly analyzes the development of home safety system and intelligent monitoring alarms that already exist, then designs a home alarm by combining image processing technology and embedded technology. This alarm can real-time monitor the house and realize remote alarm through GPRS and mobile phone.Firstly, this paper formulates design goals and design rules by analyzing the domestic and foreign market. After that, this paper introduces related knowledge about the hardware platform of STM32 and other technologies, such as embedded technology, GPRS technology and image processing technology.Secondly, this paper divide the embedded hardware system into three modules according to modular thought.They are master control module, OV7725 image capture module and GPRS wireless communication module. After that, this paper introduces the chip’s characteristics which used by each module and the interface between STM32 and chips.Thirdly, this paper researchs monitoring algorithm and image coding algorithm of JPEG. This paper not only design a algorithm that use for motion detection base on background subtraction and frame difference, but also improved the method of two times that use for image connected area labeling. After moving objects is detected, this paper extract shape features of moving objects and judge according to the features of area and length-width ratio.Finally, this paper realizes the driver of each hardware peripheral, transplantesμC/OS-II operating system and FAT file system to STM32. After that, this paper realizesthe program of send and receive MMS(SMS). The whole embedded software system is divided into four tasks base on μC/OS-II.