Underwater image restoration based on improved dark channel prior

Underwater image restoration has attracted the attention of many experts due to the demand of underwater rescue, archaeology, resource exploration et al. Water scattering and absorption hinder the linear propagation of light in water, resulting the image degradation. The degraded image visibility can be improved by the image restoration method. Many image restoration methods have been proposed by the experts for underwater images restoration. The dark channel prior method is a classical method for image dehazing, and it also can be used for underwater image restoration. However, the underwater image restored by this method still has the color distortion problem due to the water absorption, and the less visibility due to the inaccuracy transmission estimation. To overcome this problems, we propose an image restoration method based on improved dark channel prior to repair the image degraded by underwater scattering media. The quadtree decomposition is used to find the high intensity region for waterlight estimation. The transmission is estimated by the improved dark channel prior. The underwater degraded image can be restored by our proposed method without color distortion. This method will be helpful to the underwater rescue and resource exploration et al.