Hardware Implementation Of Dark Channel Perior Defogging Algorithm Based-on FPGA

With the rapid development of image processing technology and the computer vision, more and more outdoor video systems had been applied to people’s daily life. The poor visibility in foggy environment has brought many problems to the images got by the video system, such as low contrast, indistinct and color distortion, which affects the stability of the video system seriously. So it is very necessary to realize the video defogging to get clear images.In order to solve this situation, the paper designed a video defogger based-on FPGA. The core of the system design is using the method of modular design and the pipe-line technology to implement the dark channel prior algorithm, the guided filter and the image restoration model in FPGA. Because of the traditional algorithm is complex in calculation, large in computing capacity, low real-time and hard to implement in hardware, the paper had optimized the algorithm, and the algorithm optimization scheme is shown as follows:1) For the minimum filter, the paper proposed a fast minimum value calculation method which improved the parallel degree of the calculation process;2) For the binary division, the paper proposed a method that transformed the division operation process to once multiplication process and once value addressing process. The transformation simplified the computational complexity of binary division;3) For the signed numbers operation, the paper designed the status discrimination that improved the analysis and the intelligent of data processing.Through the experiment, the results show that the video defogger possess has advantages like fast operation speed and good real-time performance. It has important engineering application value.