Remote Real-time Sale Exhibition System Of Agricultural Products Based On DM643

The agricultural products network sales exhibition is an Intemet-based new marketing concept.Using its cross-sectional,high efficiency,interactive and integrated features to expand the marketing space of agricultural products so as to reduce its intermediate links in circulation, speeding up the velocity of circulation,as well as solving agricultural products "even slower sales",and enhancing the farmer's income in an effective way.This paper used the combination of digital image processing technology,the computer network communication technology,the DSP control and development technology to build up the remote real-time sale exhibition system of agricultural products.First of all,this paper made a detail introduction to the H.264 video codec standard, RTP/RTCP real-time transport protocol,TMS320DM643 multimedia processors and the related DSP development technology.The real-time video data network transmission platform was set up based on the NDK.The client-server software architecture model was divided into server systems and client systems.The server systems were embedded into hardware platform and set up an embedded Web server which provided services for the system,whereas the client systems provided the visits to server systems and controlled the camera by IE browser.Secondly,the real-time video data transmission came true after adopting the technique of RTP/RTCP.Based on the property of H.264 NAL unit and the packaging rule of RTP,this paper designed the packaging strategies for RTP/RTCP on DSP.In order to meet the demands of quality of service(QoS) in video,a FEC(forward error correction) grouping-protection technique for QoS of H.264 video delivery was proposed in this paper,in which the traditional tornado(TN) and RTP/RTCP were improved,and the NAL header and tornado(TN) code grouping-protection field was employed.Performances analysis and experimental results showed that with extra little overhead,the FEC grouping-protection for H.264 video stream could improve the quality of image better under the packet drop environment.It was easier and more flexible as compared to the traditional FEC,in which it helped to prevent missing of grouping video data,enhancing the QoS for H.264 real-time video communication.Finally,this paper discussed about the realization of network communication and embedded Web server and control function.The system has passed the test in LAN.It can realize video communication over IP and meet actual application need preferabley.