Aiming at the quality loss problems such as degradation in contrast and color distortion of image captured in haze and fog weather conditions, a single image in-depth dehazing algorithm based on optimization of the guided image was proposed. The local mean and standard deviation of the image were adopted to optimize the guided image on the basis of analysing the character of atmospheric veil. Then, the guided image was further filtered by using the dual zone filtering to get smooth and sharp-edged guided image. The atmospheric veil was estimated through the fast guided filtering. At last, a clear image would be recovered based on the atmospheric scattering physical model. The experimental results show that the recovered image is clear and natural, and rich in details. Its close view is dehazed completely, while the dehazing of its distant view is improved greatly. The proposed algorithm achieves good results where the depth of the field has a sudden saltation and improved the visibility and robustness of outdoor vision system.