Abstract: Aiming at the disadvantages of low image quality and long response time in the existed image defogging methods,we propose a fast image defogging algorithm based on luminance contrast enhancement and saturation compensation.Firstly,a color cast detection method based on color distortion factor is put forward,and correction of the images with color cast is realized through a white balance method on the basis of perfect reflection.Then,in the luminance channel of Lab color space,a luminance contrast enhancement method based on atmospheric scattering model is raised by the combination of the sky detection based atmospheric light estimation as well as the dark channel prior based transmission estimation.Finally,to improve the image quality and get color-bright and haze-free effects,we design a new saturation compensation method based on the atmospheric scattering model in the saturation channel of HSV color space,to compensate the saturation of the preliminary defogging results.Compared with the state-of-the-art defogging methods,our algorithm can effectively improve the defogging speed.Moreover,high-contrast,and clear restoration results can be obtained without color distortion.