An improved image dehazing algorithm based on dark channel prior is proposed to overcome the color distortion of sky and halo effects.The guided filter is utilized to segment the sky area finely to avoid the sky color distortion

since the defect of the classical dark channel prior theory.The global atmospheric light of image in sky region is estimated accurately.In addition

the detailed edge information can be got by taking advantage of median filter technique.So more effective transmission map estimation will be achieved which effectively inhibited the halo.Last

because the brightness of image after haze removal is lower than the actual scene

histogram equalization is used for channel V of the HSV color space.The experiment results show that.the proposed method can not only restore the clean scene from hazy images effectively

but also avoid color distortion of the sky region and halo artifacts.