Gaussian is All You Need: A Unified Framework for Solving Inverse Problems via Diffusion Posterior Sampling

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Yismaw, Nebiyou, Kamilov, Ulugbek S., Asif, M. Salman
Format: Preprint
Publié: 2024
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866916923960197120
author Yismaw, Nebiyou
Kamilov, Ulugbek S.
Asif, M. Salman
author_facet Yismaw, Nebiyou
Kamilov, Ulugbek S.
Asif, M. Salman
contents Diffusion models can generate a variety of high-quality images by modeling complex data distributions. Trained diffusion models can also be very effective image priors for solving inverse problems. Most of the existing diffusion-based methods integrate data consistency steps by approximating the likelihood function within the diffusion reverse sampling process. In this paper, we show that the existing approximations are either insufficient or computationally inefficient. To address these issues, we propose a unified likelihood approximation method that incorporates a covariance correction term to enhance the performance and avoids propagating gradients through the diffusion model. The correction term, when integrated into the reverse diffusion sampling process, achieves better convergence towards the true data posterior for selected distributions and improves performance on real-world natural image datasets. Furthermore, we present an efficient way to factorize and invert the covariance matrix of the likelihood function for several inverse problems. Our comprehensive experiments demonstrate the effectiveness of our method over several existing approaches. Code available at https://github.com/CSIPlab/CoDPS.
format Preprint
id arxiv_https___arxiv_org_abs_2409_08906
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Gaussian is All You Need: A Unified Framework for Solving Inverse Problems via Diffusion Posterior Sampling
Yismaw, Nebiyou
Kamilov, Ulugbek S.
Asif, M. Salman
Image and Video Processing
Computer Vision and Pattern Recognition
Diffusion models can generate a variety of high-quality images by modeling complex data distributions. Trained diffusion models can also be very effective image priors for solving inverse problems. Most of the existing diffusion-based methods integrate data consistency steps by approximating the likelihood function within the diffusion reverse sampling process. In this paper, we show that the existing approximations are either insufficient or computationally inefficient. To address these issues, we propose a unified likelihood approximation method that incorporates a covariance correction term to enhance the performance and avoids propagating gradients through the diffusion model. The correction term, when integrated into the reverse diffusion sampling process, achieves better convergence towards the true data posterior for selected distributions and improves performance on real-world natural image datasets. Furthermore, we present an efficient way to factorize and invert the covariance matrix of the likelihood function for several inverse problems. Our comprehensive experiments demonstrate the effectiveness of our method over several existing approaches. Code available at https://github.com/CSIPlab/CoDPS.
title Gaussian is All You Need: A Unified Framework for Solving Inverse Problems via Diffusion Posterior Sampling
topic Image and Video Processing
Computer Vision and Pattern Recognition
url https://arxiv.org/abs/2409.08906