Underwater image enhancement via multi-scale fusion and adaptive color-gamma correction in low-light conditions

In dark underwater areas, existing single-model underwater image enhancement methods have poor enhancement effects. We propose an underwater image enhancement method based on color correction and multi-scale fusion (CCMF). Specifically, we first design a color correction method with red channel compensation, which compensates for the red channel according to light attenuation and removes color bias. We propose a contrast enhancement method based on guided filtering to enhance edge texture details. The image is decomposed into a base layer and a detail layer in the logarithmic domain, with layered enhancement. Secondly, we propose an adaptive gamma correction method that dynamically adjusts correction parameters based on the gray image values. This approach prevents over-enhancement and effectively enhances the exposure in dark areas. We extract weight maps that represent different features from the input images and employ a multi-scale pyramid fusion technique to integrate the aforementioned feature information. This approach enables the mutual complementarity of various features and enhances the overall visual effect. Experimental results show that our method can effectively integrate the advantages of different enhancement methods, and the objective indicators of UCIQE, UIQM, and EG are better than other related state-of-the-art methods.