Papers › Zero-Shot Image Restoration Using Denoising Diffusion Null-Space Model

Zero-Shot Image Restoration Using Denoising Diffusion Null-Space Model

1 Dec 2022arXiv:2212.00490archive 2025-07-28

Yinhuai Wang, Jiwen Yu, Jian Zhang

Most existing Image Restoration (IR) models are task-specific, which can not be generalized to different degradation operators. In this work, we propose the Denoising Diffusion Null-Space Model (DDNM), a novel zero-shot framework for arbitrary linear IR problems, including but not limited to image super-resolution, colorization, inpainting, compressed sensing, and deblurring. DDNM only needs a pre-trained off-the-shelf diffusion model as the generative prior, without any extra training or network modifications. By refining only the null-space contents during the reverse diffusion process, we can yield diverse results satisfying both data consistency and realness. We further propose an enhanced and robust version, dubbed DDNM+, to support noisy restoration and improve restoration quality for hard tasks. Our experiments on several IR tasks reveal that DDNM outperforms other state-of-the-art zero-shot IR methods. We also demonstrate that DDNM+ can solve complex real-world applications, e.g., old photo restoration.

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wyhuai/ddnm officialmentioned in papermentioned on GitHubpytorchMIT report
andreamazzitelli/ProjectNN mentioned on GitHub report
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Tasks

ColorizationDeblurringDenoisingImage ColorizationImage Compressed SensingImage DeblurringImage InpaintingImage RestorationImage Super-ResolutionSuper-Resolutioncompressed sensing

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Image Colorization CelebA DDRM Consistency 455.9 #1 of 3 Archive leaderboard report
Image Colorization CelebA DDRM FID 31.26 #1 of 3 Archive leaderboard report
Image Colorization CelebA DDNM Consistency 26.25 #2 of 3 Archive leaderboard report
Image Colorization CelebA DDNM FID 26.44 #2 of 3 Archive leaderboard report
Image Colorization CelebA A+y Consistency 0 #3 of 3 Archive leaderboard report
Image Colorization CelebA A+y FID 68.81 #3 of 3 Archive leaderboard report
Image Colorization ImageNet DDRM Consistency 260.4 #1 of 4 Archive leaderboard report
Image Colorization ImageNet DDRM FID 36.56 #1 of 4 Archive leaderboard report
Image Colorization ImageNet DDNM Consistency 42.32 #2 of 4 Archive leaderboard report
Image Colorization ImageNet DDNM FID 36.32 #2 of 4 Archive leaderboard report
Image Colorization ImageNet A+y Consistency 0 #3 of 4 Archive leaderboard report
Image Colorization ImageNet A+y FID 43.37 #3 of 4 Archive leaderboard report
Image Colorization ImageNet DGP FID 69.54 #4 of 4 Archive leaderboard report
Image Deblurring CelebA DDNM FID 1.41 #1 of 3 Archive leaderboard report
Image Deblurring CelebA DDNM PSNR 46.72 #1 of 3 Archive leaderboard report
Image Deblurring CelebA DDNM SSIM 0.996 #1 of 3 Archive leaderboard report
Image Deblurring CelebA DDRM FID 6.24 #2 of 3 Archive leaderboard report
Image Deblurring CelebA DDRM PSNR 43.07 #2 of 3 Archive leaderboard report
Image Deblurring CelebA DDRM SSIM 0.993 #2 of 3 Archive leaderboard report
Image Deblurring CelebA A+y FID 54.31 #3 of 3 Archive leaderboard report
Image Deblurring CelebA A+y PSNR 18.85 #3 of 3 Archive leaderboard report
Image Deblurring CelebA A+y SSIM 0.741 #3 of 3 Archive leaderboard report
Image Deblurring ImageNet DDNM FID 1.15 #1 of 3 Archive leaderboard report
Image Deblurring ImageNet DDNM PSNR 44.93 #1 of 3 Archive leaderboard report
Image Deblurring ImageNet DDNM SSIM 0.994 #1 of 3 Archive leaderboard report
Image Deblurring ImageNet DDRM FID 1.48 #2 of 3 Archive leaderboard report
Image Deblurring ImageNet DDRM PSNR 43.01 #2 of 3 Archive leaderboard report
Image Deblurring ImageNet DDRM SSIM 0.992 #2 of 3 Archive leaderboard report
Image Deblurring ImageNet A+y FID 55.42 #3 of 3 Archive leaderboard report
Image Deblurring ImageNet A+y PSNR 18.56 #3 of 3 Archive leaderboard report
Image Deblurring ImageNet A+y SSIM 0.6616 #3 of 3 Archive leaderboard report
Image Inpainting CelebA DDNM FID 4.54 #1 of 5 Archive leaderboard report
Image Inpainting CelebA DDNM PSNR 35.64 #1 of 5 Archive leaderboard report
Image Inpainting CelebA DDNM SSIM 0.982 #1 of 5 Archive leaderboard report
Image Inpainting CelebA DDRM FID 12.53 #2 of 5 Archive leaderboard report
Image Inpainting CelebA DDRM PSNR 34.79 #2 of 5 Archive leaderboard report
Image Inpainting CelebA DDRM SSIM 0.978 #2 of 5 Archive leaderboard report
Image Inpainting CelebA RePaint FID 14.19 #3 of 5 Archive leaderboard report
Image Inpainting CelebA RePaint PSNR 35.2 #3 of 5 Archive leaderboard report
Image Inpainting CelebA RePaint SSIM 0.981 #3 of 5 Archive leaderboard report
Image Inpainting CelebA A+y FID 181.56 #4 of 5 Archive leaderboard report
Image Inpainting CelebA A+y PSNR 15.57 #4 of 5 Archive leaderboard report
Image Inpainting CelebA A+y SSIM 0.809 #4 of 5 Archive leaderboard report
Image Inpainting ImageNet DDNM FID 3.89 #2 of 5 Archive leaderboard report
Image Inpainting ImageNet DDNM PSNR 32.06 #2 of 5 Archive leaderboard report
Image Inpainting ImageNet DDNM SSIM 0.968 #2 of 5 Archive leaderboard report
Image Inpainting ImageNet DDRM FID 4.82 #3 of 5 Archive leaderboard report
Image Inpainting ImageNet DDRM PSNR 31.73 #3 of 5 Archive leaderboard report
Image Inpainting ImageNet DDRM SSIM 0.966 #3 of 5 Archive leaderboard report
Image Inpainting ImageNet RePaint FID 12.31 #4 of 5 Archive leaderboard report
Image Inpainting ImageNet RePaint PSNR 31.87 #4 of 5 Archive leaderboard report
Image Inpainting ImageNet RePaint SSIM 0.963 #4 of 5 Archive leaderboard report
Image Inpainting ImageNet A+y FID 72.71 #5 of 5 Archive leaderboard report
Image Inpainting ImageNet A+y PSNR 14.52 #5 of 5 Archive leaderboard report
Image Inpainting ImageNet A+y SSIM 0.799 #5 of 5 Archive leaderboard report
Image Super-Resolution CelebA DDNM FID 22.27 #1 of 5 Archive leaderboard report
Image Super-Resolution CelebA DDNM PSNR 31.63 #1 of 5 Archive leaderboard report
Image Super-Resolution CelebA DDNM SSIM 0.945 #1 of 5 Archive leaderboard report
Image Super-Resolution CelebA ILVR FID 29.82 #2 of 5 Archive leaderboard report
Image Super-Resolution CelebA ILVR PSNR 31.59 #2 of 5 Archive leaderboard report
Image Super-Resolution CelebA ILVR SSIM 0.945 #2 of 5 Archive leaderboard report
Image Super-Resolution CelebA DDRM FID 31.04 #3 of 5 Archive leaderboard report
Image Super-Resolution CelebA DDRM PSNR 31.63 #3 of 5 Archive leaderboard report
Image Super-Resolution CelebA DDRM SSIM 0.945 #3 of 5 Archive leaderboard report
Image Super-Resolution CelebA PULSE FID 40.33 #4 of 5 Archive leaderboard report
Image Super-Resolution CelebA PULSE PSNR 22.74 #4 of 5 Archive leaderboard report
Image Super-Resolution CelebA PULSE SSIM 0.623 #4 of 5 Archive leaderboard report
Image Super-Resolution CelebA A+y FID 103.3 #5 of 5 Archive leaderboard report
Image Super-Resolution CelebA A+y PSNR 27.27 #5 of 5 Archive leaderboard report
Image Super-Resolution CelebA A+y SSIM 0.782 #5 of 5 Archive leaderboard report
Image Super-Resolution ImageNet DDNM FID 39.26 #2 of 6 Archive leaderboard report
Image Super-Resolution ImageNet DDNM PSNR 27.46 #2 of 6 Archive leaderboard report
Image Super-Resolution ImageNet DDNM SSIM 0.87 #2 of 6 Archive leaderboard report
Image Super-Resolution ImageNet DDRM FID 43.15 #3 of 6 Archive leaderboard report
Image Super-Resolution ImageNet DDRM PSNR 27.38 #3 of 6 Archive leaderboard report
Image Super-Resolution ImageNet DDRM SSIM 0.869 #3 of 6 Archive leaderboard report
Image Super-Resolution ImageNet ILVR FID 43.66 #4 of 6 Archive leaderboard report
Image Super-Resolution ImageNet ILVR PSNR 27.4 #4 of 6 Archive leaderboard report
Image Super-Resolution ImageNet ILVR SSIM 0.87 #4 of 6 Archive leaderboard report
Image Super-Resolution ImageNet DGP FID 64.34 #5 of 6 Archive leaderboard report
Image Super-Resolution ImageNet DGP PSNR 23.18 #5 of 6 Archive leaderboard report
Image Super-Resolution ImageNet DGP SSIM 0.798 #5 of 6 Archive leaderboard report
Image Super-Resolution ImageNet A+y FID 134.4 #6 of 6 Archive leaderboard report
Image Super-Resolution ImageNet A+y PSNR 24.26 #6 of 6 Archive leaderboard report
Image Super-Resolution ImageNet A+y SSIM 0.684 #6 of 6 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

Diffusion

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