Research And Design Of The Cable Surface Image Acquisition And Transmission System Based On DSP

Cable as the main bearing member of the cable-stayed bridge, the surface damage to the bridge led to great insecurity. So, its detection must be accurate and efficient. Image capture and transmission technology based on image recognition has become a research hotspot to replace the traditional manual inspection. Compared with traditional manual inspection, it has low cost and high safety with a wide range of applications.Therefore, the cable surface image acquisition and transmission system development has an important research significance.Through analysis background and research status of the issues, a new type of DM642-based image acquisition of the cable defect and transmission system was presented, and the system design and development was completed. The system consists of both client and server components. Client constitutes of DM642 platform, three-way CCD camera, CPLD, Ethernet and GPRS wireless modem,and it is in charge of the surface of the cable image acquisition, storage, processing and transmission. Server consists of a PC accessed of the internet network,and it is responsible for receiving image data, decoding, real-time display and preservation.This paper introduces the GPRS network technology and DSP technology associated with the system and then the overall design of the system and block diagram of the hardware is made.Based on this, this paper focuses on transmission of the image via web and wireless transmission implementation based on GPRS technology is extended. Network transmission system is divided into hardware and software design two parts. In hardware design part, it introduces hardware interface design in image acquisition, Ethernet transmission and the principle of implement in CPLD control module. In software part, it introduces the client and server programming.Clients-side include image capture, JPEG compression and network transmission programming.Server-side include image reception, decoding, real-time display and preservation programming.The wireless transmission section introduces the wireless module interface design, GPRS modem access GPRS web and data transceiver through a wireless modem.Finally, it introduces the whole system experimental conditions. The experiment results show that the system can capture images and transmit to the server in the ground in real time, and the intended target of this subject is achieved.