Research On Improved Dark Channel Prior Defog Algorithm

In the mist environment,image captured by outdoor imaging devices,especially fog image containing sky bright region,the image defogged by the classic single image defog algorithm emerges problems of color distortion and detail lost,halo etc.To solve the above problems,puts forward an improved dark channel prior defog algorithm,named IDCPDA.The algorithm firstly makes use of weighted quad tree to obtain more accurate the global atmospheric value,then exploits multiple-structure element morphological open and close filter towards the minimum channel map to obtain a rough scattering map by dark channel prior,makes use of variogram to correct the transmittance map,and uses bilateral filtering for the smooth operation,finally gets recovery images by image degradation model,and makes contrast adjustment to get bright,clear and no fog image.A large number of experimental results show that the proposed defog method in this paper can be good to remove the fog,recover color and definition of the fog image containing close range image,image perspective,the image including the bright areas very well,compared with other image defog algorithms,obtain more clear and natural fog free images with details of higher visibility,what's more,the relationship between the time complexity of IDCPDA algorithm and the number of image pixels is a linear correlation.