Title
A modified multi-grid algorithm for a novel variational model to remove multiplicative noise.
Abstract
This paper proposes a novel variational model and a fast algorithm for its numerical approximation to remove multiplicative noise from digital images.By applying a maximum a posteriori (MAP), we obtained a strictly convex objective functional whose minimization leads to non-linear PDEs.To this end, we develop an efficient non-linear multi-grid algorithm with an improved smoother and also discuss a local Fourier analysis of the associated smoothers which leads to a new and more effective smoother.Experimental results using both synthetic and realistic images, illustrate advantages of our proposed model in visual improvement as well as an increase in the PSNR over comparing to related recent corresponding PDE methods.We compare numerical results of new multi-grid algorithm via modified smoother with traditional time marching schemes and with multi-grid method via (local and global) fixed point smoother as well. This paper proposes a novel variational model and a fast algorithm for its numerical approximation to remove multiplicative noise from digital images. By applying a maximum a posteriori (MAP), we obtained a strictly convex objective functional whose minimization leads to non-linear partial differential equations. As a result, developing a fast numerical scheme is difficult because of the high nonlinearity and stiffness of the associated Euler-Lagrange equation and standard unilevel iterative methods are not appropriate. To this end, we develop an efficient non-linear multi-grid algorithm with an improved smoother. We also discuss a local Fourier analysis of the associated smoothers which leads to a new and more effective smoother. Experimental results using both synthetic and realistic images, illustrate advantages of our proposed model in visual improvement as well as an increase in the peak signal-to-noise ratio over comparing to related recent corresponding PDE methods. We compare numerical results of new multigrid algorithm via modified smoother with traditional time marching schemes and with multigrid method via (local and global) fixed point smoother as well.
Year
DOI
Venue
2016
10.1016/j.jvcir.2016.07.016
J. Visual Communication and Image Representation
Keywords
Field
DocType
Maximum a posteriori (MAP),Total variation,Additive operator splitting,Multi-grid,Multiplicative noise,Convex function
Nonlinear system,Iterative method,Algorithm,Convex function,Maximum a posteriori estimation,Fixed point,Partial differential equation,Multigrid method,Multiplicative noise,Mathematics
Journal
Volume
Issue
ISSN
40
PB
1047-3203
Citations 
PageRank 
References 
1
0.35
27
Authors
4
Name
Order
Citations
PageRank
Asmat Ullah151.45
W. Chen231049.17
Hongguang Sun317420.60
Mushtaq Ahmad Khan451.79