Design And Implementation Of Video Acquisition And Wireless Transmission System In Barley Field

Barley is not only an important crop in the northwest of China,but an essential ingredient in the production of beer.The timely field management,such as diseases and insects control in barley growth,has a direct impact on the final yield and quality of barley.In recently years,with the rapid development of information science and computer network technology,video monitoring systems have also got constant improvement and innovation from the early to the digital surveillance.With the advantages of low cost,small volume,high reliability,good extensibilitye and high flexibility,the embedded networking video surveillance system has gradually become a main digital monitoring system with broad application prospects.This paper presents a new design implementation of image acquisition and wireless transmission system in barley field,which is based on embedded controller and image sensor and wireless communication technology.The system architecture which a modular design method was adopted in mainly composed of the video capture module,wireless transmission device and monitoring network terminal.The final realization of hardware and software in barley field image acquisition and wireless transmission are discussed in detail.This paper mainly completed the following research works in requirements analysis,design and development.(1)The overall design Under the analyses of system requirements and comparison,based on the priority of economic and technical performance,the main module components and parameter specifications such as embedded processor,Zig Bee network node device,image sensor,wireless communication protocol,wireless bridge which was used to connect wireless LAN(Local Area Network)to wired LAN,Linux operating system and so on were determined one after another,after the overall technical scheme design of the system was completed.(2)The selection and design of system hardware In order to adapt to the barley image acquisition and reliable video transmission on the field,with reference to new technology and previous research results of the project,the hardware system equipments as to S3C6410 processor,OV9650 CMOS image sensor,wireless network card 88w8686 and solar photovoltaic power supply system were chosen,and the hardware platform of the system was constructed or fabricated.(3)The design and development of embedded system First the environment of Linuxoperating system was set up for the program of micro controller,including the installation of cross compiler and the selection of virtual machine,before the C language was used to the software design in the embedded system.Then the integration of engineering programs for file sharing between virtual machine and the host,bootloader transplantation,Linux kernel transplantation and root file system transplant were separately programed.(4)Video acquisition and processing software development In this system Video4 Linux program was used to capture barley video images,then H.264 standard was applied for video coding and ffmpeg H.264 for majorization decoding,and where RTP / RTCP protocol was selected and used in video transmission.(5)The system performance experiment After the several rounds of barley image acquisition and transmission experiments were carried out,the experimental results showed that the system performance met the design requirements,and the data compression rate was between93% and 98%,and the transmission error rate within 2%.Therefore,this new barley field image acquisition and transmission system had some reference significance for the development of similar agricultural surveillance facilities.