Feature Dense Relevance Network for Single Image Dehazing

Abstract

Existing learning-based dehazing methods do not fully use non-local information, which makes the restoration of seriously degraded region very tough. We propose a novel dehazing network by defining the Feature Dense Relevance module (FDR) and the Shallow Feature Mapping module (SFM). The FDR is defined based on multi-head attention to construct the dense relationship between different local features in the whole image. It enables the network to restore the degraded local regions by non-local information in complex scenes. In addition, the raw distant skip-connection easily leads to artifacts while it cannot deal with the shallow features effectively. Therefore, we define the SFM by combining the atmospheric scattering model and the distant skip-connection to effectively deal with the shallow features in different scales. It not only maps the degraded textures into clear textures by distant dependence, but also reduces artifacts and color distortions effectively. We introduce contrastive loss and focal frequency loss in the network to obtain a realitic and clear image. The extensive experiments on several synthetic and real-world datasets demonstrate that our network surpasses most of the state-of-the-art methods.