Design Of Real-time Image Defogging System Based On FPGA

In foggy weather,the scattering effect of particles in the atmosphere will lead to a significant decline in the quality of the image,and the details of the image are seriously covered.Image degradation will seriously affect the development of video surveillance,camera,navigation control,target tracking and other work.Therefore,it is necessary to study image defogging.At present,most of the algorithms are based on the algorithm and use software for image defogging.These algorithms need some specific prior conditions,and the processing speed is slow,so they are not suitable for the scene that needs real-time defogging.In order to solve this problem,this paper designs a real-time image defogging system based on FPGA.Firstly,the framework of the real-time defogging system is designed.The original fog image acquisition module is designed on FPGA development board,the cache image module is designed by using SDRAM controller,and the Ethernet module is designed to complete the transmission of fog image.Secondly,this paper studies the current image defogging algorithm.Through analysis and comparison,the dark channel prior algorithm is finally selected.In view of the high complexity of the algorithm and the characteristics of FPGA,the algorithm is improved and optimized: fast minimum filtering for the original image,improving the speed of the algorithm,using a new method to quickly calculate the atmospheric light value,using guided filtering for transmittance thinning.On the premise of ensuring the effect of defogging,the algorithm is more simple and efficient.Finally,the hardware logic design of dark channel acquisition,transmittance calculation,large phosgene value calculation and other modules is completed.The improved image defogging algorithm is implemented on FPGA.Finally,the system performance is tested and verified.The correctness of Ethernet transmission is tested,and the effect of real-time image defogging system is tested.The results show that the real-time defogging system designed in this paper has good defogging effect,and can meet the requirements of real-time.It has a certain application value.