Depth-Aware Unpaired Video Dehazing.

This paper investigates a novel unpaired video dehazing framework, which can be a good candidate in practice by relieving pressure from collecting paired data. In such a paradigm, two key issues including 1) temporal consistency uninvolved in single image dehazing, and 2) better dehazing ability need to be considered for satisfied performance. To handle the mentioned problems, we alternatively resort to introducing depth information to construct additional regularization and supervision. Specifically, we attempt to synthesize realistic motions with depth information to improve the effectiveness and applicability of traditional temporal losses, and thus better regularizing the spatiotemporal consistency. Moreover, the depth information is also considered in terms of adversarial learning. For haze removal, the depth information guides the local discriminator to focus on regions where haze residuals are more likely to exist. The dehazing performance is consequently improved by more pertinent guidance from our depth-aware local discriminator. Extensive experiments are conducted to validate our effectiveness and superiority over other competitors. To the best of our knowledge, this study is the initial foray into the task of unpaired video dehazing. Our code is available at https://github.com/YaN9-Y/DUVD.

PUGAN: Physical Model-Guided Underwater Image Enhancement Using GAN With Dual-Discriminators.

Due to the light absorption and scattering induced by the water medium, underwater images usually suffer from some degradation problems, such as low contrast, color distortion, and blurring details, which aggravate the difficulty of downstream underwater understanding tasks. Therefore, how to obtain clear and visually pleasant images has become a common concern of people, and the task of underwater image enhancement (UIE) has also emerged as the times require. Among existing UIE methods, Generative Adversarial Networks (GANs) based methods perform well in visual aesthetics, while the physical model-based methods have better scene adaptability. Inheriting the advantages of the above two types of models, we propose a physical model-guided GAN model for UIE in this paper, referred to as PUGAN. The entire network is under the GAN architecture. On the one hand, we design a Parameters Estimation subnetwork (Par-subnet) to learn the parameters for physical model inversion, and use the generated color enhancement image as auxiliary information for the Two-Stream Interaction Enhancement sub-network (TSIE-subnet). Meanwhile, we design a Degradation Quantization (DQ) module in TSIE-subnet to quantize scene degradation, thereby achieving reinforcing enhancement of key regions. On the other hand, we design the Dual-Discriminators for the style-content adversarial constraint, promoting the authenticity and visual aesthetics of the results. Extensive experiments on three benchmark datasets demonstrate that our PUGAN outperforms state-of-the-art methods in both qualitative and quantitative metrics. The code and results can be found from the link of https://rmcong.github.io/proj_PUGAN.html.

Designing an Illumination-Aware Network for Deep Image Relighting.

Lighting is a determining factor in photography that affects the style, expression of emotion, and even quality of images. Creating or finding satisfying lighting conditions, in reality, is laborious and time-consuming, so it is of great value to develop a technology to manipulate illumination in an image as post-processing. Although previous works have explored techniques based on the physical viewpoint for relighting images, extensive supervisions and prior knowledge are necessary to generate reasonable images, restricting the generalization ability of these works. In contrast, we take the viewpoint of image-to-image translation and implicitly merge ideas of the conventional physical viewpoint. In this paper, we present an Illumination-Aware Network (IAN) which follows the guidance from hierarchical sampling to progressively relight a scene from a single image with high efficiency. In addition, an Illumination-Aware Residual Block (IARB) is designed to approximate the physical rendering process and to extract precise descriptors of light sources for further manipulations. We also introduce a depth-guided geometry encoder for acquiring valuable geometry- and structure-related representations once the depth information is available. Experimental results show that our proposed method produces better quantitative and qualitative relighting results than previous state-of-the-art methods. The code and models are publicly available on https://github.com/NK-CS-ZZL/IAN.