Automated Tuning for Diffusion Inverse Problem Solvers without Generative Prior Retraining

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Alçalar, Yaşar Utku, Yun, Junno, Akçakaya, Mehmet
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866912584599339008
author Alçalar, Yaşar Utku
Yun, Junno
Akçakaya, Mehmet
author_facet Alçalar, Yaşar Utku
Yun, Junno
Akçakaya, Mehmet
contents Diffusion/score-based models have recently emerged as powerful generative priors for solving inverse problems, including accelerated MRI reconstruction. While their flexibility allows decoupling the measurement model from the learned prior, their performance heavily depends on carefully tuned data fidelity weights, especially under fast sampling schedules with few denoising steps. Existing approaches often rely on heuristics or fixed weights, which fail to generalize across varying measurement conditions and irregular timestep schedules. In this work, we propose Zero-shot Adaptive Diffusion Sampling (ZADS), a test-time optimization method that adaptively tunes fidelity weights across arbitrary noise schedules without requiring retraining of the diffusion prior. ZADS treats the denoising process as a fixed unrolled sampler and optimizes fidelity weights in a self-supervised manner using only undersampled measurements. Experiments on the fastMRI knee dataset demonstrate that ZADS consistently outperforms both traditional compressed sensing and recent diffusion-based methods, showcasing its ability to deliver high-fidelity reconstructions across varying noise schedules and acquisition settings.
format Preprint
id arxiv_https___arxiv_org_abs_2509_09880
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Automated Tuning for Diffusion Inverse Problem Solvers without Generative Prior Retraining
Alçalar, Yaşar Utku
Yun, Junno
Akçakaya, Mehmet
Image and Video Processing
Artificial Intelligence
Computer Vision and Pattern Recognition
Machine Learning
Medical Physics
Diffusion/score-based models have recently emerged as powerful generative priors for solving inverse problems, including accelerated MRI reconstruction. While their flexibility allows decoupling the measurement model from the learned prior, their performance heavily depends on carefully tuned data fidelity weights, especially under fast sampling schedules with few denoising steps. Existing approaches often rely on heuristics or fixed weights, which fail to generalize across varying measurement conditions and irregular timestep schedules. In this work, we propose Zero-shot Adaptive Diffusion Sampling (ZADS), a test-time optimization method that adaptively tunes fidelity weights across arbitrary noise schedules without requiring retraining of the diffusion prior. ZADS treats the denoising process as a fixed unrolled sampler and optimizes fidelity weights in a self-supervised manner using only undersampled measurements. Experiments on the fastMRI knee dataset demonstrate that ZADS consistently outperforms both traditional compressed sensing and recent diffusion-based methods, showcasing its ability to deliver high-fidelity reconstructions across varying noise schedules and acquisition settings.
title Automated Tuning for Diffusion Inverse Problem Solvers without Generative Prior Retraining
topic Image and Video Processing
Artificial Intelligence
Computer Vision and Pattern Recognition
Machine Learning
Medical Physics
url https://arxiv.org/abs/2509.09880