Spatio-Spectral Feature Fusion for Low-Light Image Enhancement

Low-light image enhancement aims to improve an image's visual quality, which is essential for many downstream computer vision and multimedia tasks. Existing spatial-domain enhancement methods barely focus on the regions containing object boundaries, which take the most informative characteristics. However, solely focusing on enhancing high-frequency details not only causes over-sharpening of an image but also leads to color distortion. In this letter, we propose a novel spatio-spectral feature fusion network (S2F2N), that involves a frequency-feature representation branch (FRB) and a spatial-feature representation branch (SRB) to learn the domain-specific representation individually. Moreover, a spatial-channel mixed attention block (MAB) is introduced to learn the joint representation of spatio-spectral features for final image relighting. Extensive experiments on several benchmark datasets demonstrate that our method can produce high fidelity results for low-light images.