Low-Light Image Enhancement Under Non-uniform Dark

Authors: Li, Y., Cai, F., Tu, Y. and Ding, Y.

Conference: International Conference on Multimedia Modeling

Dates: 9-12 January 2023

Abstract:

The low visibility of low-light images due to lack of exposure poses a significant challenge for vision tasks such as image fusion, detection and segmentation in low-light conditions. Real-world situations such as backlighting and shadow occlusion mostly exist with non-uniform low-light, while existing enhancement methods tend to brighten both low-light and normal-light regions, we actually prefer to enhance dark regions but suppress overexposed regions. To address this problem, we propose a new non-uniform dark visual network (NDVN) that uses the attention mechanism to enhance regions with different levels of illumination separately. Since deep-learning needs strong data-driven, for this purpose we carefully construct a non-uniform dark synthetic dataset (UDL) that is larger and more diverse than existing datasets, and more importantly it contains more non-uniform light states. We use the manually annotated luminance domain mask (LD-mask) in the dataset to drive the network to distinguish between low-light and extremely dark regions in the image. Guided by the LD-mask and the attention mechanism, the NDVN adaptively illuminates different light regions while enhancing the color and contrast of the image. More importantly, we introduce a new region loss function to constrain the network, resulting in better quality enhancement results. Extensive experiments show that our proposed network outperforms other state-of-the-art methods both qualitatively and quantitatively.

Source: Manual