Papers › Shadow Removal via Shadow Image Decomposition
Shadow Removal via Shadow Image Decomposition
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.
In Syntology Open this paper in Syntology's Atlas, the map of the papers in Syntology's graph and their citations.
For agents, Syntology's MCP tool lists every function and class Syntology harvested from this paper and whether it ran (how to connect): get_harvested_code_for_paper(arxiv_id="1908.08628")
Code
Syntology Ran 0 of 11 code samples harvested from 2 repositories linked to this paper; 11 have no recorded run.
By repository: official repository: 3 samples from 1 repository, 0 ran; community (archive-listed): 8 samples from 1 repository, 0 ran. The run record, sample by sample. “Ran” means executed on a synthesized input, not that the code is correct or reproduces the paper.
Repository list and official/mentioned flags are the archive's, frozen 2025-07-28. Reachability, where shown, is from one Syntology probe window (2026-09-16 to 2026-09-18); repositories not probed show nothing. GitHub stars are not tracked.
Code Syntology ran Syntology
11 samples harvested; 0 ran; 0 honoured the contract we drafted; 11 have no recorded run. Read from Syntology's graph 2026-09-24; that is when this build read the record, not when the samples ran.
Licence: 0 of the 11 samples are pointer only, meaning Syntology does not serve that copy's text. This page shows no code text for any sample; each one links to its file in the repository.
Harvested from 2 repositories linked to this paper, official or community; each sample names its own and says which. “Ran” means the sample executed on a synthesized input. It does not mean the output is correct, and nothing here reproduces the paper's results. “Honoured” and “violated” refer to a contract Syntology drafted from the code itself; “our draft was wrong” and “fixture could not drive it” are failures of Syntology's instrument, not of the code.
Each sample ends with its code_sha256, Syntology's identity for that exact code. An agent fetches the stored sample with Syntology's MCP tool get_code(code_sha256="…") (how to connect); click an identity to copy that call.
Repository labels, per sample. official repository: The archive marks this repository official for the paper. named in the paper: The archive records that the paper mentions this repository; it is not marked official. community (archive-listed): In the archive's code links for this paper, not marked official and not recorded as mentioned in the paper. found in paper text by Syntology: Syntology found this repository in the paper's own text; whether it is the authors' implementation is not asserted. community: Not in the archive's code links for this paper; a community repository Syntology harvested. Samples from a repository marked official are listed first. Licence labels name the repository's licence as recorded at harvest. “Pointer only” means Syntology does not serve that copy's text, for one of four reasons: no licence file was found; the licence was not identified; the licence is recorded as permissive but that copy's record is not marked cleared; or the licence is outside the permissive list Syntology serves text under (MIT, Apache-2.0, BSD and similar). Some licences outside that list permit redistribution, such as WTFPL, and GPL-3.0 under its conditions; they are simply not on the list. Hover a licence label for the reason. File links open the file on GitHub at the default branch, which may have changed since the harvest.
16bd26484cba3e49 · report
c0d7139178892d99 · report
d61e18f527623b40 · report
7b6ac2089343d3c3 · report
700b6c26b9f820a8 · report
063e4397662f061e · report
5a112feba8f53b0c · report
30d56fdfbf93d0d3 · report
c1ebd10caa104c75 · report
ea2359b6d27138f3 · report
3e5e64c86e05a9f1 · report
Tasks
Results from the paper archive 2025-07-28
| Task | Dataset | Model | Metric | Value | Rank at snapshot | Leaderboard | Report |
|---|---|---|---|---|---|---|---|
| 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
Report a problem or propose a change · a person checks every report against the paper or source before anything changes; decisions are listed on /corrections