The Design Of The Industrial Image Acquisition And Pre-processing System Based On FPGA

In recent years, FPGA has been widely used in the monitoring of the industrial production process, ultra high speed signal processing and real-time control because of its super-large scale and ultra high-speed. The paper takes the industrial image which is easily affected by optoelectronic noise and has a simple edge in civilian industrial equipment field as the research object, according to advantage of the FPGA when it is applied in real-time industrial image acquisition and pre-processing field, presents a design project of the industrial image acquisition and pre-processing system based on FPGA. The paper describes the design idea and implementation process of system, its main contents are as follows:Firstly, studies the designing scheme of the hardware platform.Designs the drive circuit of the CMOS image sensor in the image acquisition terminal; Finishes the model selection of FPGA, SRAM, SDRAM and FLASH in main board control model in system control terminal. Designs the drive circuit of LCD in image display terminal.Secondly, expounds the implementation of the memory interface. Takes a 8Mbits SRAM as the cache in image preprocessing stage, implements the ping-pong operation in single SRAM with the control of FPGA; Takes a 256Mbits SDRAM:as the video memory, implements the ping-pang operation in single SDRAM with the control to the L-BANK in SDRAM.Thirdly, describes the image preprocessing algorithm in detail.Improves the medianflltering algorithm and edge detection algorithm according to the characteristics of industrial image. Presents a method to get the median quickly, reduces the consumption of hardware resources and improves the speed of the median filtering, presents a simple edge detection algorithm according to the characteristics of the industrial image to be edge detected, can detect the edge of industrial image in special industrial situation with simple logic and fewer hardware resources. Both algorithms are designed by pipeline design method, gives full play to the advantage of FPGA.Fourthly, implements the SOPC platform. Designs the SOPC with NIOSII processor, configures the parameters of each module during the system design process, improves the flexibility of system.In the end, the paper presents the performance optimization scheme of the overall system and the system is actually tested, the results show that the system designed in paper can realize the acquisition and display of industrial image and can be used for a simple image preprocessing, has reached the desired research purpose.