Marginal multi-object multi-frame blind deconvolution

TL;DR

This paper introduces a marginal estimator for multi-object multi-frame blind deconvolution in solar imaging, improving robustness, regularization, and ease of implementation over traditional joint estimation methods.

Contribution

A novel marginal estimator that enhances regularization, contrast control, and simplifies implementation for blind deconvolution in solar imaging.

Findings

The method prevents noise from being misattributed to aberrations.

It is less sensitive to hyperparameters, enabling automatic tuning.

The approach is easily integrated into existing pipelines and open-source.

Abstract

High-resolution ground-based solar imaging relies heavily on multi-object multi-frame blind deconvolution to correct for atmospheric turbulence. However, the traditional joint maximum likelihood estimation methods in which object and the atmospheric aberrations are estimated together face some problems. In this paper, we introduce a marginal estimator for the multi-object multi-frame blind deconvolution problem. By employing a framework to marginalize over the observed objects, we develop a reconstruction method that offers several distinct advantages over joint estimation. First, the marginalization provides enhanced regularization that naturally accounts for object uncertainty, successfully preventing the reconstruction algorithm from erroneously assigning noise to high-order aberrations. Second, the marginal estimator yields more contrast control, as it is much less sensitive to the hyperparameters dictating the power spectral density (PSD) of the object. This robustness allows these hyperparameters to be optimized, enabling a ``plug-and-play'' deployment that removes the need for manual tuning. Finally, we demonstrate that the proposed method is accessible and simple to implement, requiring only the addition of a log-determinant term to the traditional merit function. With minimal modifications required for existing blind deconvolution pipelines, the estimator has been fully integrated into the open-source torchmfbd package for its use by the solar physics community.