Paper ID | IMT-1.11 | ||
Paper Title | PROVABLE CONVERGENCE OF PLUG-AND-PLAY PRIORS WITH MMSE DENOISERS | ||
Authors | Xiaojian Xu, Yu Sun, Jiaming Liu, Washington University in St. Louis, United States; Brendt Wohlberg, Los Alamos National Laboratory, United States; Ulugbek S. Kamilov, Washington University in St. Louis, United States | ||
Session | IMT-1: Computational Imaging Learning-based Models | ||
Location | Area J | ||
Session Time: | Tuesday, 21 September, 08:00 - 09:30 | ||
Presentation Time: | Tuesday, 21 September, 08:00 - 09:30 | ||
Presentation | Poster | ||
Topic | Computational Imaging Methods and Models: Learning-Based Models | ||
Abstract | Plug-and-play priors (PnP) is a methodology for regularized image reconstruction that specifies the prior through an image denoiser. While PnP algorithms are well understood for denoisers performing maximum a posteriori probability (MAP) estimation, they have not been analyzed for the minimum mean squared error (MMSE) denoisers. This letter addresses this gap by establishing the first theoretical convergence result for the iterative shrinkage/thresholding algorithm (ISTA) variant of PnP for MMSE denoisers. We show that the iterates produced by PnP-ISTA with an MMSE denoiser converge to a stationary point of some global cost function. We validate our analysis on sparse signal recovery in compressive sensing by comparing two types of denoisers, namely the exact MMSE denoiser and the approximate MMSE denoiser obtained by training a deep neural net. |