Papers › Dream the Impossible: Outlier Imagination with Diffusion Models

Dream the Impossible: Outlier Imagination with Diffusion Models

23 Sep 2023NeurIPS 2023 11arXiv:2309.13415archive 2025-07-28

Xuefeng Du, Yiyou Sun, Xiaojin Zhu, Yixuan Li

Utilizing auxiliary outlier datasets to regularize the machine learning model has demonstrated promise for out-of-distribution (OOD) detection and safe prediction. Due to the labor intensity in data collection and cleaning, automating outlier data generation has been a long-desired alternative. Despite the appeal, generating photo-realistic outliers in the high dimensional pixel space has been an open challenge for the field. To tackle the problem, this paper proposes a new framework DREAM-OOD, which enables imagining photo-realistic outliers by way of diffusion models, provided with only the in-distribution (ID) data and classes. Specifically, DREAM-OOD learns a text-conditioned latent space based on ID data, and then samples outliers in the low-likelihood region via the latent, which can be decoded into images by the diffusion model. Different from prior works, DREAM-OOD enables visualizing and understanding the imagined outliers, directly in the pixel space. We conduct comprehensive quantitative and qualitative studies to understand the efficacy of DREAM-OOD, and show that training with the samples generated by DREAM-OOD can benefit OOD detection performance. Code is publicly available at https://github.com/deeplearning-wisc/dream-ood.

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deeplearning-wisc/dream-ood officialmentioned in papermentioned on GitHubpytorch report

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2ran · violated contract
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get_class_names deeplearning-wisc/dream-ood/scripts/dream_ood.py official repository ran · our draft was wrong licence not identified · pointer only · 10dfa7de61b0b5db · report
rand_bbox deeplearning-wisc/dream-ood/scripts/train_gene_in100.py official repository unverified licence not identified · pointer only · d34a085d71b8f4b5 · report
recursion_change_bn deeplearning-wisc/dream-ood/scripts/train_ood_det_in100.py official repository unverified licence not identified · pointer only · 0cc8a17c73df40ee · report
cosine_annealing identical code first harvested elsewhere ran · violated contract fingerprinted licence of this copy not recorded · 05eda95f9800a1e9 · report
chunk identical code first harvested elsewhere ran · our draft was wrong licence of this copy not recorded · 8241c0562bc710fd · report
numpy_to_pil identical code first harvested elsewhere ran · violated contract licence of this copy not recorded · 1e63d588563eb90a · report

Tasks

Out of Distribution (OOD) Detection

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Methods

Diffusion

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