The 16th European Conference on Computer Vision 2020.

Global and Local Enhancement Networks for Paired and Unpaired Image Enhancement

Han-Ul Kim
hanulkim@mcl.korea.ac.kr
Korea University

Young Jun Koh
yjkoh@cnu.ac.kr
Chungnam National University.

Chang-Su Kim
changsukim@korea.ac.kr
Korea University

Abstract

A novel approach for paired and unpaired image enhancement is proposed in this work. First, we develop global enhancement network (GEN) and local enhancement network (LEN), which can faithfully enhance images. The proposed GEN performs the channel-wise intensity transforms that can be trained easier than the pixel-wise prediction. The proposed LEN refines GEN results based on spatial filtering. Second, we propose different training schemes for paired learning and unpaired learning to train GEN and LEN. Especially, we propose a two-stage training scheme based on generative adversarial networks for unpaired learning. Experimental results demonstrate that the proposed algorithm outperforms the state-of-the-arts in paired and unpaired image enhancement. Notably, the proposed unpaired image enhancement algorithm provides better results than recent state-of-the-art paired image enhancement algorithms. The source codes and trained models are available at https://github.com/hukim1124/GleNet.

Overview of the proposed method

Paired image enhancement on the MIT Adobe 5K dataset.

Input
DUPE
Proposed
Photographer C

Unpaired image enhancement on the MIT Adobe 5K dataset.

Input
FRL
Proposed
Photographer C

Cite

@inproceedings{kim2020global,
    title = {Global and Local Enhancement Networks for Paired and Unpaired Image Enhancement},
    author = {Kim, Han-Ul and Koh, Young Jun and Kim, Chang-Su},
    booktitle = {European Conference on Computer Vision},
    year = {2020}
}

Links

Paper and Github