Papers › Shadow Removal via Shadow Image Decomposition

Shadow Removal via Shadow Image Decomposition

23 Aug 2019ICCV 2019 10arXiv:1908.08628archive 2025-07-28

Hieu Le, Dimitris Samaras

We propose a novel deep learning method for shadow removal. Inspired by physical models of shadow formation, we use a linear illumination transformation to model the shadow effects in the image that allows the shadow image to be expressed as a combination of the shadow-free image, the shadow parameters, and a matte layer. We use two deep networks, namely SP-Net and M-Net, to predict the shadow parameters and the shadow matte respectively. This system allows us to remove the shadow effects on the images. We train and test our framework on the most challenging shadow removal dataset (ISTD). Compared to the state-of-the-art method, our model achieves a 40% error reduction in terms of root mean square error (RMSE) for the shadow area, reducing RMSE from 13.3 to 7.9. Moreover, we create an augmented ISTD dataset based on an image decomposition system by modifying the shadow parameters to generate new synthetic shadow images. Training our model on this new augmented ISTD dataset further lowers the RMSE on the shadow area to 7.4.

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lmhieu612/SID officialmentioned on GitHubpytorchMIT report
cvlab-stonybrook/SID mentioned on GitHubpytorchMIT report
naoto0804/SynShadow mentioned on GitHubpytorchMIT report

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im_darken lmhieu612/SID/data_processing/dataset_augmentation.py official repository unverified MIT (permissive) · 16bd26484cba3e49 · report
im_relit lmhieu612/SID/data_processing/compute_params.py official repository unverified MIT (permissive) · c0d7139178892d99 · report
relit lmhieu612/SID/data_processing/compute_params.py official repository unverified MIT (permissive) · d61e18f527623b40 · report
apply_tone_curve naoto0804/SynShadow/src/util/illum_affine_model.py community (archive-listed) unverified MIT (permissive) · 7b6ac2089343d3c3 · report
copyconf naoto0804/SynShadow/src/util/util.py community (archive-listed) unverified MIT (permissive) · 700b6c26b9f820a8 · report
find_image naoto0804/SynShadow/src/util/image.py community (archive-listed) unverified MIT (permissive) · 063e4397662f061e · report
load naoto0804/SynShadow/src/util/image.py community (archive-listed) unverified MIT (permissive) · 5a112feba8f53b0c · report
load_obj naoto0804/SynShadow/src/util/util.py community (archive-listed) unverified MIT (permissive) · 30d56fdfbf93d0d3 · report
rgb_to_srgb naoto0804/SynShadow/src/util/illum_affine_model.py community (archive-listed) unverified MIT (permissive) · c1ebd10caa104c75 · report
srgb_to_rgb naoto0804/SynShadow/src/util/illum_affine_model.py community (archive-listed) unverified MIT (permissive) · ea2359b6d27138f3 · report
tile_images naoto0804/SynShadow/src/util/util.py community (archive-listed) unverified MIT (permissive) · 3e5e64c86e05a9f1 · report

Tasks

Shadow Removal

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Shadow Removal ISTD+ SP+M-Net (ICCV 2019) (512x512) LPIPS 0.183 #4 of 26 Archive leaderboard report
Shadow Removal ISTD+ SP+M-Net (ICCV 2019) (512x512) PSNR 28.31 #4 of 26 Archive leaderboard report
Shadow Removal ISTD+ SP+M-Net (ICCV 2019) (512x512) RMSE 2.96 #4 of 26 Archive leaderboard report
Shadow Removal ISTD+ SP+M-Net (ICCV 2019) (512x512) SSIM 0.866 #4 of 26 Archive leaderboard report
Shadow Removal ISTD+ SP+M-Net (ICCV 2019) (256x256) LPIPS 0.373 #15 of 26 Archive leaderboard report
Shadow Removal ISTD+ SP+M-Net (ICCV 2019) (256x256) PSNR 26.58 #15 of 26 Archive leaderboard report
Shadow Removal ISTD+ SP+M-Net (ICCV 2019) (256x256) RMSE 3.37 #15 of 26 Archive leaderboard report
Shadow Removal ISTD+ SP+M-Net (ICCV 2019) (256x256) SSIM 0.717 #15 of 26 Archive leaderboard report
Shadow Removal SRD SP+M-Net (ICCV 2019) (512x512) LPIPS 0.269 #14 of 25 Archive leaderboard report
Shadow Removal SRD SP+M-Net (ICCV 2019) (512x512) PSNR 24.89 #14 of 25 Archive leaderboard report
Shadow Removal SRD SP+M-Net (ICCV 2019) (512x512) RMSE 4.35 #14 of 25 Archive leaderboard report
Shadow Removal SRD SP+M-Net (ICCV 2019) (512x512) SSIM 0.792 #14 of 25 Archive leaderboard report
Shadow Removal SRD SP+M-Net (ICCV 2019) (256x256) LPIPS 0.444 #23 of 25 Archive leaderboard report
Shadow Removal SRD SP+M-Net (ICCV 2019) (256x256) PSNR 22.25 #23 of 25 Archive leaderboard report
Shadow Removal SRD SP+M-Net (ICCV 2019) (256x256) RMSE 5.68 #23 of 25 Archive leaderboard report
Shadow Removal SRD SP+M-Net (ICCV 2019) (256x256) SSIM 0.636 #23 of 25 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

Methods

1x1 ConvolutionAverage PoolingBatch NormalizationConvolutionGlobal Average PoolingGrouped ConvolutionKaiming InitializationReLUResNeXtResNeXt BlockResidual Connection

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