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arXiv · 2408.13868

Particle-Filtering-based Latent Diffusion for Inverse Problems

Amir Nazemi·Mohammad Hadi Sepanj·Nicholas Pellegrino·Chris Czarnecki·Paul Fieguth
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Abstract

Current strategies for solving image-based inverse problems apply latent diffusion models to perform posterior sampling.However, almost all approaches make no explicit attempt to explore the solution space, instead drawing only a single sample from a Gaussian distribution from which to generate their solution. In this paper, we introduce a particle-filtering-based framework for a nonlinear exploration of the solution space in the initial stages of reverse SDE methods. Our proposed particle-filtering-based latent diffusion (PFLD) method and proposed problem formulation and framework can be applied to any diffusion-based solution for linear or nonlinear inverse problems. Our experimental results show that PFLD outperforms the SoTA solver PSLD on the FFHQ-1K and ImageNet-1K datasets on inverse problem tasks of super resolution, Gaussian debluring and inpainting.

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Amir Nazemi, Mohammad Hadi Sepanj, Nicholas Pellegrino, Chris Czarnecki, Paul Fieguth. 2026-07-29. Particle-Filtering-based Latent Diffusion for Inverse Problems. https://arxiv.org/abs/2408.13868

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