DMML: Deep Multi-Prior and Multi-Discriminator Learning for Underwater Image Enhancement

Enhancing the quality of the images acquired under the water environments is crucial in many broadcast technologies. As the richness of the features generated by deep underwater image enhancement networks improves, the visual signals with higher qualities can be yielded. In view of this, in this paper, we propose a new deep network for the task of underwater image enhancement, in which the network feature generation process is guided by the prior information obtained from various underwater medium transmission map and atmospheric light estimation methods. Further, in order to obtain high values for different image quality assessment metrics associated with the images produced by the proposed network, we introduce a multi-stage training process for our network. In the first stage, the proposed network is trained with the conventional supervised learning technique, whereas, in the second stage, the training process of the network is carried out by the adversarial learning technique. Finally, in the third stage, the training of the network obtained by the conventional supervised learning is continued by the guidance of the one trained by the adversarial learning technique. In the development of the adversarial learning-based stage of our network, we propose a novel multi-discriminator generative adversarial network, which is able to produce images with more realistic textures and structures. The proposed multi-discriminator generative adversarial network employs the discrimination process between the real and fake data in various underwater environment color spaces. The results of different experimentations show the effectiveness of the proposed scheme in restoring the high-quality images compared to the other state-of-the-art deep underwater image enhancement networks.