Simplifying Low-Light Image Enhancement Networks with Relative Loss Functions

TL;DR

This paper introduces FLW-Net, a lightweight network with relative loss functions, to simplify low-light image enhancement while effectively addressing issues like noise, low contrast, and color deviation.

Contribution

The paper proposes a novel, efficient global feature extraction module and relative loss functions to reduce network complexity and improve low-light image enhancement performance.

Findings

Significantly reduces network complexity

Improves enhancement quality in low-light images

Demonstrates effectiveness through comparative experiments

Abstract

Image enhancement is a common technique used to mitigate issues such as severe noise, low brightness, low contrast, and color deviation in low-light images. However, providing an optimal high-light image as a reference for low-light image enhancement tasks is impossible, which makes the learning process more difficult than other image processing tasks. As a result, although several low-light image enhancement methods have been proposed, most of them are either too complex or insufficient in addressing all the issues in low-light images. In this paper, to make the learning easier in low-light image enhancement, we introduce FLW-Net (Fast and LightWeight Network) and two relative loss functions. Specifically, we first recognize the challenges of the need for a large receptive field to obtain global contrast and the lack of an absolute reference, which limits the simplification of network structures in this task. Then, we propose an efficient global feature information extraction component and two loss functions based on relative information to overcome these challenges. Finally, we conducted comparative experiments to demonstrate the effectiveness of the proposed method, and the results confirm that the proposed method can significantly reduce the complexity of supervised low-light image enhancement networks while improving processing effect. The code is available at \url{https://github.com/hitzhangyu/FLW-Net}.