I. Introduction
The underwater research based on the extreme environment plays a vital role in the study of the ocean. The Underwater Internet of Things (Underwater IoT) system forms a crucial foundation for humanity’s exploration of the enigmatic depths of the ocean, offering a wealth of possibilities in areas, such as the collection of marine mineral resources, monitoring of the marine ecological environment, and various military applications. Nonetheless, owing to the light’s absorption and scattering in the aquatic medium, underwater images captured by Underwater IoT systems in extreme conditions frequently contend with issues like color distortion, blurred details, and inadequate contrast. This is because of the color distortion caused by the attenuation of the wavelength of light underwater, which increases with distance. Red light with longer wavelengths decays the fastest and is most affected compared to green and blue light. In addition, the scattering effect increases with distance, reducing the contrast of underwater images and causing blurring [1]. Therefore, finding an effective imaging method in Underwater IoT systems is of great significance for the perception of Marine information.