Papers › Auto-Exposure Fusion for Single-Image Shadow Removal

Auto-Exposure Fusion for Single-Image Shadow Removal

1 Mar 2021CVPR 2021 1arXiv:2103.01255archive 2025-07-28

Lan Fu, Changqing Zhou, Qing Guo, Felix Juefei-Xu, Hongkai Yu, Wei Feng, Yang Liu, Song Wang

Shadow removal is still a challenging task due to its inherent background-dependent and spatial-variant properties, leading to unknown and diverse shadow patterns. Even powerful state-of-the-art deep neural networks could hardly recover traceless shadow-removed background. This paper proposes a new solution for this task by formulating it as an exposure fusion problem to address the challenges. Intuitively, we can first estimate multiple over-exposure images w.r.t. the input image to let the shadow regions in these images have the same color with shadow-free areas in the input image. Then, we fuse the original input with the over-exposure images to generate the final shadow-free counterpart. Nevertheless, the spatial-variant property of the shadow requires the fusion to be sufficiently `smart', that is, it should automatically select proper over-exposure pixels from different images to make the final output natural. To address this challenge, we propose the shadow-aware FusionNet that takes the shadow image as input to generate fusion weight maps across all the over-exposure images. Moreover, we propose the boundary-aware RefineNet to eliminate the remaining shadow trace further. We conduct extensive experiments on the ISTD, ISTD+, and SRD datasets to validate our method's effectiveness and show better performance in shadow regions and comparable performance in non-shadow regions over the state-of-the-art methods. We release the model and code in https://github.com/tsingqguo/exposure-fusion-shadow-removal.

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GradientLoss CV-Reimplementation/AEFNet-Reimplementation/models/Fusion_model.py community (archive-listed) ran · metamorphic tier: deterministic no licence file found · pointer only · 973bfc25e8f16d63 · report
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FusionModel CV-Reimplementation/AEFNet-Reimplementation/models/Fusion_model.py community (archive-listed) unverified no licence file found · pointer only · ffad6ea71a6ce1ff · report
PoissonGradientLoss CV-Reimplementation/AEFNet-Reimplementation/models/Fusion_model.py community (archive-listed) unverified no licence file found · pointer only · 5162d854ad287b25 · report

Tasks

Image Shadow RemovalShadow Removal

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Shadow Removal ISTD+ Auto (CVPR 2021) (512x512) LPIPS 0.189 #6 of 26 Archive leaderboard report
Shadow Removal ISTD+ Auto (CVPR 2021) (512x512) PSNR 28.07 #6 of 26 Archive leaderboard report
Shadow Removal ISTD+ Auto (CVPR 2021) (512x512) RMSE 2.99 #6 of 26 Archive leaderboard report
Shadow Removal ISTD+ Auto (CVPR 2021) (512x512) SSIM 0.853 #6 of 26 Archive leaderboard report
Shadow Removal ISTD+ Auto (CVPR 2021) (256x256) LPIPS 0.365 #21 of 26 Archive leaderboard report
Shadow Removal ISTD+ Auto (CVPR 2021) (256x256) PSNR 26.1 #21 of 26 Archive leaderboard report
Shadow Removal ISTD+ Auto (CVPR 2021) (256x256) RMSE 3.53 #21 of 26 Archive leaderboard report
Shadow Removal ISTD+ Auto (CVPR 2021) (256x256) SSIM 0.718 #21 of 26 Archive leaderboard report
Shadow Removal SRD Auto (CVPR 2021) (512x512) LPIPS 0.247 #19 of 25 Archive leaderboard report
Shadow Removal SRD Auto (CVPR 2021) (512x512) PSNR 24.32 #19 of 25 Archive leaderboard report
Shadow Removal SRD Auto (CVPR 2021) (512x512) RMSE 4.71 #19 of 25 Archive leaderboard report
Shadow Removal SRD Auto (CVPR 2021) (512x512) SSIM 0.8 #19 of 25 Archive leaderboard report
Shadow Removal SRD Auto (CVPR 2021) (256x256) LPIPS 0.37 #22 of 25 Archive leaderboard report
Shadow Removal SRD Auto (CVPR 2021) (256x256) PSNR 23.2 #22 of 25 Archive leaderboard report
Shadow Removal SRD Auto (CVPR 2021) (256x256) RMSE 5.37 #22 of 25 Archive leaderboard report
Shadow Removal SRD Auto (CVPR 2021) (256x256) SSIM 0.694 #22 of 25 Archive leaderboard report

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