Underwater image restoration based on secondary guided transmission map.

The color distortion and low contrast of underwater images are caused by the absorption of light by water and the scattering of suspended particles. So, we propose an underwater image restoration method based on secondary guided transmission map, which can effectively restore the color, visibility and natural appearance of underwater image. We use improved guided filter to refine the transmission map. Firstly, the rough transmission map is decomposed into the basic image and the detail image by the guided filter. And then refined transmission map is reconstructed after processing the images respectively. Finally, auto level processing is conducted on the restored image to improve the contrast of the image. In order to evaluate the effectiveness of our method, qualitative and quantitative comparisons and application test are carried out. Experimental results demonstrate that compared with several state-of-the-art methods, the proposed method can get genuine color, natural appearance, and the improvement of visibility and contrast. [ABSTRACT FROM AUTHOR]