Abstract

Due to the cost limitation of camera sensors, images captured in low-light environments often suffer from low contrast and multiple types of noise. A number of algorithms have been proposed to improve contrast and suppress noise in the input low-light images. In this paper, a deep refinement network, LL-RefineNet, is built to learn from the synthetical dark and noisy training images, and perform image enhancement for natural low-light images in symmetric—forward and backward—pathways. The proposed network utilizes all the useful information from the down-sampling path to produce the high-resolution enhancement result, where global features captured from deeper layers are gradually refined using local features generated by earlier convolutions. We further design the training loss for mixed noise reduction. The experimental results show that the proposed LL-RefineNet outperforms the comparative methods both qualitatively and quantitatively with fast processing speed on both synthetic and natural low-light image datasets.

Highlights

  • Video surveillance is of vital importance for various automated decision-making tasks including security application and medical care [1,2,3]

  • Guo et al [37] proposed a low-light image enhancement (LIME) method, which estimated the illumination of each pixel and utilized illumination map estimation

  • In contrast to most traditional image enhancement methods which only deal with the single type of Gaussian noise using L2 loss, we further introduce L1 loss for sparse impulse noise, which is closer to the enhancement of real low-light images

Read more

Summary

Introduction

Video surveillance is of vital importance for various automated decision-making tasks including security application and medical care [1,2,3]. It is very important to design effective algorithms to process and enhance the low-light images in video surveillance systems. Methods based on deep learning framework have drawn enormous interest due to their effectiveness [9,10,11,12,13,14,15,16,17,18,19,20,21] These approaches are superior to previous traditional algorithms in multiple areas of computer vision, including object recognition [22], object detection [23], semantic segmentation [3], super resolution [24], and image denoising [25]. The content of the paper is organized as: related work is reviewed, which introduces recent algorithms for low-light image improvement and deep learning based image processing tasks.

Traditional Low-Light Image Enhancement Methods
Deep Learning Methods in Image Process Applications
Deep Learning Methods for Low-Light Image Enhancement
Refinement in Symmetric Pathways
LL-RefineNet
Loss for Mixed Noise
Network Training and Training Data Generation
Experiments and Results Analysis
Compared Methods
Quantitative Evaluation
Qualitative Evaluation
Running Time
Conclusions
Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.