In this paper, we propose a 2-stage low-light image enhancement method called
Self-Reference Deep Adaptive Curve Estimation (Self-DACE). In the first stage,
we present an intuitive, lightweight, fast, and unsupervised luminance
enhancement algorithm. The algorithm is based on a novel low-light enhancement
curve that can be used to locally boost image brightness. We also propose a new
loss function with a simplified physical model designed to preserve natural
images' color, structure, and fidelity. We use a vanilla CNN to map each pixel
through deep Adaptive Adjustment Curves (AAC) while preserving the local image
structure. Secondly, we introduce the corresponding denoising scheme to remove
the latent noise in the darkness. We approximately model the noise in the dark
and deploy a Denoising-Net to estimate and remove the noise after the first
stage. Exhaustive qualitative and quantitative analysis shows that our method
outperforms existing state-of-the-art algorithms on multiple real-world
datasets.

本文提出了一种称为自参考深度自适应曲线估计（Self-DACE）的两阶段低光图像增强方法。第一阶段介绍了一种直观、轻量级、快速和无监督的亮度增强算法，该算法基于一种新颖的低光增强曲线，可用于本地增强图像亮度。同时，我们提出了一个新的损失函数，配备了一个简化的物理模型，旨在保留自然图像的颜色、结构和保真度。我们使用一个普通的 CNN 通过深度自适应调整曲线（AAC）对每个像素进行映射，同时保留局部图像结构。其次，我们引入相应的降噪方案来去除图像中存在的噪声。我们对暗部噪声进行了近似建模，并使用降噪网络在第一阶段后估计和去除噪声。全面的定性和定量分析显示，我们的方法在多个实际数据集上优于现有的最先进算法。