Underwater image enhancement based on color-line model and homomorphic filtering

The underwater images suffer from low contrast, low visibility and color deviation which caused by scattering and absorption. In this paper, the method based on color-line model and homomorphic filtering is proposed to enhance the underwater image. First of all, the homomorphic filtering is used to remove the color deviation in the underwater image and the obtained image will be used for subsequent processes. Then, the transmission of the underwater image is estimated through the solution of the offsets that the color lines along the background-light vector from the origin. We develop a non-convex optimization function to obtain the transmission of the underwater image. Finally, the color correction is added in the underwater image which obtained by the color-line method. The simulation experiments results show that the proposed method is superior to the current state-of-the-art methods in the four aspects of quantitative analysis, qualitative analysis, color accuracy analysis, and restoring synthesized underwater images.