Suyash P. Awate


 
Feature-Preserving Patch-Based MRI Denoising :
A Nonparametric Empirical-Bayes Approach
 
Suyash P. Awate, Ross T. Whitaker
Feature-Preserving MRI Denoising: A Nonparametric Empirical Bayes Approach
IEEE Trans. Med. Imaging 2007, 26(9):1242-1255
 
 
Bayesian Image Denoising: The Key Problem
(1) How to model the prior (i.e. Markov statistics of noiseless signal) ?
(2) How to estimate the prior ?
 
Challenges Using Pre-Tuned Parametric Priors
(1) Strong models on signal
(2) Parameters of the model tuned (incorrectly) by hand or via training
mri denoising, image denoising
 
Key Idea : Nonparametric Empirical-Bayes Estimation
(1) Model the prior, i.e. Markov statistics of the noiseless signal, using nonparametric statistical schemes
(2) Estimate the prior from the image that is to be denoised, knowing the noise model
(3) Use this estimate of the prior for optimal Bayesian denoising
 
 
Estimating the Prior
mri denoising, image denoising
 
 
Bayesian Denoising by Iterated Conditional Entropy Reduction (ICER)
mri denoising, image denoising
 
Denoised Images
mri denoising, image denoising
 
 
Residual Images
= difference between denoised image and noiseless image
mri denoising, image denoising
 
Validation : Quantitative (BrainWeb repository)
mri denoising, image denoising
 
Denoised a Real MR Image
mri denoising, image denoising
 
 
Related Work
 
Recent Trends in Denoising
 

Iterative Nonlocal Means, or UINTA

 
T. Weissman, E. Ordentlich, G. Seroussi, S. Verdu, and M. Weinberger
Universal discrete denoising: Known channel
IEEE Trans. Information Theory 2005, 51(1):5-28
DUDE and Extensions
 
H. Robbins
The empirical Bayes approach to statistical decision problems
Annals of Mathematical Statistics 1964, 35(1):1-20
 
H. Robbins
An empirical Bayes approach to statistics
In Proc. Third Berkeley Symp. Math. Stat. Prob. 1964, pp.157-164