no code implementations • 8 Apr 2024 • Hong Ye Tan, Ziruo Cai, Marcelo Pereyra, Subhadip Mukherjee, Junqi Tang, Carola-Bibiane Schönlieb
Unsupervised learning is a training approach in the situation where ground truth data is unavailable, such as inverse imaging problems.
1 code implementation • 30 Nov 2023 • Tobías I. Liaudat, Matthijs Mars, Matthew A. Price, Marcelo Pereyra, Marta M. Betcke, Jason D. McEwen
This work proposes a method coined QuantifAI to address UQ in radio-interferometric imaging with data-driven (learned) priors for high-dimensional settings.
1 code implementation • 18 Oct 2023 • Julian Tachella, Marcelo Pereyra
Scientific imaging problems are often severely ill-posed, and hence have significant intrinsic uncertainty.
1 code implementation • 18 Aug 2023 • Teresa Klatzer, Paul Dobson, Yoann Altmann, Marcelo Pereyra, Jesús María Sanz-Serna, Konstantinos C. Zygalakis
This discretisation is asymptotically unbiased for Gaussian targets and shown to converge in an accelerated manner for any target that is $\kappa$-strongly log-concave (i. e., requiring in the order of $\sqrt{\kappa}$ iterations to converge, similarly to accelerated optimisation schemes), comparing favorably to [M. Pereyra, L. Vargas Mieles, K. C.
1 code implementation • 30 Jun 2023 • Jason D. McEwen, Tobías I. Liaudat, Matthew A. Price, Xiaohao Cai, Marcelo Pereyra
Proximal nested sampling was introduced recently to open up Bayesian model selection for high-dimensional problems such as computational imaging.
1 code implementation • 28 Jun 2022 • Marcelo Pereyra, Luis A. Vargas-Mieles, Konstantinos C. Zygalakis
Additionally, instead of viewing the augmented posterior distribution as an approximation of the original model, we propose to consider it as a generalisation of this model.
no code implementations • 11 Jun 2022 • Subhadip Mukherjee, Andreas Hauptmann, Ozan Öktem, Marcelo Pereyra, Carola-Bibiane Schönlieb
In recent years, deep learning has achieved remarkable empirical success for image reconstruction.
no code implementations • 16 Jan 2022 • Rémi Laumont, Valentin De Bortoli, Andrés Almansa, Julie Delon, Alain Durmus, Marcelo Pereyra
Bayesian methods to solve imaging inverse problems usually combine an explicit data likelihood function with a prior distribution that explicitly models expected properties of the solution.
no code implementations • 18 Mar 2021 • Matthew Holden, Marcelo Pereyra, Konstantinos C. Zygalakis
Bayesian computation is performed by using a parallel tempered version of the preconditioned Crank-Nicolson algorithm on the manifold, which is shown to be ergodic and robust to the non-convex nature of these data-driven models.
no code implementations • 8 Mar 2021 • Rémi Laumont, Valentin De Bortoli, Andrés Almansa, Julie Delon, Alain Durmus, Marcelo Pereyra
The proposed algorithms are demonstrated on several canonical problems such as image deblurring, inpainting, and denoising, where they are used for point estimation as well as for uncertainty visualisation and quantification.
no code implementations • 11 Feb 2020 • Kelvin Shuangjian Zhang, Gabriel Peyré, Jalal Fadili, Marcelo Pereyra
In this paper, we consider Langevin diffusions on a Hessian-type manifold and study a discretization that is closely related to the mirror-descent scheme.
1 code implementation • 26 Nov 2019 • Ana F. Vidal, Valentin De Bortoli, Marcelo Pereyra, Alain Durmus
In this work, we propose a general empirical Bayesian method for setting regularisation parameters in imaging problems that are convex w. r. t.
Methodology Computation 62C12, 65C40, 68U10, 62F15, 65J20, 65C60, 65J22
no code implementations • 5 Feb 2015 • Marcelo Pereyra, Steve McLaughlin
This paper presents a new Bayesian estimation technique for hidden Potts-Markov random fields with unknown regularisation parameters, with application to fast unsupervised K-class image segmentation.