Papers › Unpaired Image-to-Image Translation via Neural Schrödinger Bridge

Unpaired Image-to-Image Translation via Neural Schrödinger Bridge

24 May 2023arXiv:2305.15086archive 2025-07-28

Beomsu Kim, Gihyun Kwon, Kwanyoung Kim, Jong Chul Ye

Diffusion models are a powerful class of generative models which simulate stochastic differential equations (SDEs) to generate data from noise. While diffusion models have achieved remarkable progress, they have limitations in unpaired image-to-image (I2I) translation tasks due to the Gaussian prior assumption. Schr\"{o}dinger Bridge (SB), which learns an SDE to translate between two arbitrary distributions, have risen as an attractive solution to this problem. Yet, to our best knowledge, none of SB models so far have been successful at unpaired translation between high-resolution images. In this work, we propose Unpaired Neural Schr\"{o}dinger Bridge (UNSB), which expresses the SB problem as a sequence of adversarial learning problems. This allows us to incorporate advanced discriminators and regularization to learn a SB between unpaired data. We show that UNSB is scalable and successfully solves various unpaired I2I translation tasks. Code: \url{https://github.com/cyclomon/UNSB}

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PatchNCELoss cyclomon/unsb/models/sb_model.py official repository ran fingerprinted MIT (permissive) · ae8b241e01fcddc6 · report
cal_gradient_penalty cyclomon/UNSB/models/losses_sesim.py official repository ran MIT (permissive) · 37a68ec0a708024d · report
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get_timestep_embedding cyclomon/UNSB/models/ncsn_networks.py official repository ran fingerprinted MIT (permissive) · 4f8e8738883964be · report
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BaseModel cyclomon/unsb/models/sb_model.py official repository unverified MIT (permissive) · 2f1eaf0eb0587b5f · report
SBModel cyclomon/unsb/models/sb_model.py official repository unverified MIT (permissive) · d9415f0546e4093d · report
get_file_paths cyclomon/UNSB/datasets/detect_cat_face.py official repository unverified MIT (permissive) · cefa735e77f924d4 · report
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Tasks

Image-to-Image TranslationTranslation

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Methods

Diffusion

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