In order to avoid the problem that the color distortion and the details are not obvious, this paper presents an improved defogging algorithm. It uses the dark channel prior to estimate the atmospheric light and the transmission and proposes a new gradient domain filtering to refine the transmission. Then, the intensity compensation is used to enhance the image color information. At the same time, the atmospheric light value is estimated and boundary constrains is used to roughly estimate the transmission, and, weights is added to define the transmission. So the scene transmission of both is re...