LIVENet
Low-light Image Denoising and Enhancement

WACV 2024

(1) Independent Researcher (2) IIT Roorkee (3) Green PMU Semi Pvt Ltd
† Work done while the author was an intern at IIT Roorkee

Overview

LIVENet is a low-light image enhancement approach (a) that restores realistic colors while reducing noise and (b) recover texture with realistic colours. The values in parenthesis are (PSNR/SSIM) metrics.

Abstract

Low-light image enhancement (LLIE) is the process of improving the quality of images taken in low-light conditions while striking a balance between enhancing image illumination and maintaining their natural appearance. This involves reducing noise, enhancing details, and correcting colors, all while avoiding unwanted artifacts such as halo effects or color distortions. We propose LIVENet, a novel deep neural network that jointly performs noise reduction on low-light images and enhances illumination and texture details. LIVENet has two stages: the image enhancement stage and the refinement stage. We propose a Latent Subspace Denoising Block (LSDB) that uses a low-rank representation of low-light features to suppress the noise and predict a noise-free grayscale image. We propose enhancing an RGB image by eliminating noise. This is done by converting it into YCbCr color space and then replacing the noisy luminance (Y) channel with the predicted noisefree grayscale image. LIVENet also predicts the transmission map and atmospheric light in the image enhancement stage. By feeding them to an atmospheric scattering model, LIVENet produces an enhanced image with rich color and illumination. In the refinement stage, we propose an enhancement approach where texture information from the grayscale image is incorporated into the improved image using a Spatial Feature Transform (SFT) layer. Experiments on different datasets demonstrate that LIVENet's enhanced images consistently outperform previous techniques across various quality metrics.

Method

Architecture diagraam and outputs of various modules in LIVENet. The blue values are (PSNR/SSIM/MAE/LPIPS) metrics. A transmission map and a grayscale image are single-channel; hence, these metrics are not shown. The improvement in PSNR and SSIM from [Noisy] coarse map (19.94/0.66) to the Denoised coarse map (27.35/0.75) demonstrates the usefulness of the GSIP and LSDB modules. The improvement in SSIM and LPIPS from the denoised coarse map (0.75/0.18) to Inormal (0.93/0.11) shows the efficacy of the refinement stage and SFT layers.

Qualitative results

Results on the LOLv1 dataset

For each example, we show (from left to right) (i) the input low light image (ii) normal light output of proposed method


Results on the LOLv2 dataset

For each example, we show (from left to right) (i) the input low light image (ii) normal light output of proposed method

Using LIVENet

A novel network for real-world low-light image denoising and enhancement.

You can try LIVENet using the pretrained weights and test code. We provide a test code for running LIVENet on low light image in the github repository.

BibTeX

@inproceedings{makwana2024livenet,
    title={LIVENet: A novel network for real-world low-light image denoising and enhancement},
    author={Makwana, Dhruv and Deshmukh, Gayatri and Susladkar, Onkar and Mittal, Sparsh and Teja, R},
    booktitle={Proceedings of the IEEE/CVF Winter Conference on Applications of Computer Vision},
    year={2024}
  } 

Acknowledgements

This work was Supported by Science and Engineering Research Board, India under the project CRG/2022/003821.