A Deep Retinex Framework for Light Field Restoration under Low-light Conditions

Abstract

Light field (LF) images can record the scene from multiple directions and have many applications, such as refocusing and depth estimation. However, these applications can be heavily influenced by poor light condition and noise. This work aims to recover the high-quality LF images from their lowlight detection. First, a decomposition network is employed to decompose each LF image into its reflectance and illumination with the Retinex theory. Then, two enhancement networks are designed to denoise the reflectance and enhance the illumination, respectively. They adopt alternate spatial-angular feature extractions and process all the views synchronously with high efficiency. A parallel dual attention mechanism is integrated to both the spatial and angular feature extractions, to encode more important information. Moreover, a discriminator is introduced during the training to generate more realistic LF images by making judgment according to both the spatial and angular characteristics. Experimental results have demonstrated the superior performance of our method, which can restore the content, luminance, color and geometric structures of LF images effectively.