Papers › Stochastic Conditional Diffusion Models for Robust Semantic Image Synthesis

Stochastic Conditional Diffusion Models for Robust Semantic Image Synthesis

26 Feb 2024arXiv:2402.16506archive 2025-07-28

Juyeon Ko, Inho Kong, Dogyun Park, Hyunwoo J. Kim

Semantic image synthesis (SIS) is a task to generate realistic images corresponding to semantic maps (labels). However, in real-world applications, SIS often encounters noisy user inputs. To address this, we propose Stochastic Conditional Diffusion Model (SCDM), which is a robust conditional diffusion model that features novel forward and generation processes tailored for SIS with noisy labels. It enhances robustness by stochastically perturbing the semantic label maps through Label Diffusion, which diffuses the labels with discrete diffusion. Through the diffusion of labels, the noisy and clean semantic maps become similar as the timestep increases, eventually becoming identical at t=T. This facilitates the generation of an image close to a clean image, enabling robust generation. Furthermore, we propose a class-wise noise schedule to differentially diffuse the labels depending on the class. We demonstrate that the proposed method generates high-quality samples through extensive experiments and analyses on benchmark datasets, including a novel experimental setup simulating human errors during real-world applications. Code is available at https://github.com/mlvlab/SCDM.

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SPADEGroupNorm mlvlab/scdm/guided_diffusion/unet.py official repository ran MIT (permissive) · 2093f8abdf7b5c3e · report
CondTimestepBlock mlvlab/scdm/guided_diffusion/unet.py official repository unverified MIT (permissive) · f857d1d316bcb04b · report
SCDResBlock mlvlab/scdm/guided_diffusion/unet.py official repository unverified MIT (permissive) · 5823d8bc8de0e785 · report
calculate_frechet_distance mlvlab/SCDM/evaluations/fid/tests_with_FID.py official repository unverified MIT (permissive) · 0def50a351111624 · report

Tasks

Conditional Image GenerationImage GenerationImage-to-Image TranslationNoisy Semantic Image Synthesis

Datasets

Introduced by this paper, per the archive.

noisy-ADE20K-DSnoisy-ADE20K-Edgenoisy-ADE20K-Random

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Conditional Image Generation CelebAMask-HQ SCDM FID 17.4 #1 of 1 Archive leaderboard report
Conditional Image Generation CelebAMask-HQ SCDM LPIPS 0.418 #1 of 1 Archive leaderboard report
Conditional Image Generation CelebAMask-HQ SCDM mIoU 77.2 #1 of 1 Archive leaderboard report
Image-to-Image Translation ADE20K Labels-to-Photos SCDM FID 26.9 #3 of 16 Archive leaderboard report
Image-to-Image Translation ADE20K Labels-to-Photos SCDM LPIPS 0.530 #3 of 16 Archive leaderboard report
Image-to-Image Translation ADE20K Labels-to-Photos SCDM mIoU 49.4 #3 of 16 Archive leaderboard report
Image-to-Image Translation COCO-Stuff Labels-to-Photos SCDM FID 15.3 #3 of 15 Archive leaderboard report
Image-to-Image Translation COCO-Stuff Labels-to-Photos SCDM LPIPS 0.519 #3 of 15 Archive leaderboard report
Image-to-Image Translation COCO-Stuff Labels-to-Photos SCDM mIoU 38.1 #3 of 15 Archive leaderboard report
Noisy Semantic Image Synthesis noisy-ADE20K-DS SCDM FID 32.4 #1 of 1 Archive leaderboard report
Noisy Semantic Image Synthesis noisy-ADE20K-DS SCDM mIoU 44.7 #1 of 1 Archive leaderboard report
Noisy Semantic Image Synthesis noisy-ADE20K-Edge SCDM FID 31.2 #1 of 1 Archive leaderboard report
Noisy Semantic Image Synthesis noisy-ADE20K-Edge SCDM mIoU 40.1 #1 of 1 Archive leaderboard report
Noisy Semantic Image Synthesis noisy-ADE20K-Random SCDM FID 28.1 #1 of 1 Archive leaderboard report
Noisy Semantic Image Synthesis noisy-ADE20K-Random SCDM mIoU 45.1 #1 of 1 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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