ADJWINDOWONPPGRID
Adjoint W operator, adjoint subband windowing with 2D FFT
Contents
Description
Y = ADJWINDOWONPPGRID(Y,N,R,BETA)
x: array (2,(R*n)+1,n+1) : (sector,radial,slope) 2 sectors.
beta: 2 or 4; scaling factor 2^j or 4^j.
R: oversampling rate
y: digital shearlet coefficients which is a cell array:
each y{sector,scale,tile} is a complex-valued matrix, 2D FFT
sector runs through 4 values
scale runs through J approx log(N)/log(beta/2) values
tile runs through Ntile approx beta^scale values [OUCH!]Examples
R = 4; beta = 4;
img = imread('barbara.gif');
img = double(img);
N = size(img,1);
pimg = ppFT(img,R);
shX = WindowOnPPGrid(pimg,beta,0);
size(shX)
tpimg= AdjWindowOnPPGrid(shX,N,R,beta);
size(tpimg)
norm(squeeze(tpimg(1,:,:)-pimg(1,:,:)),inf)
norm(squeeze(tpimg(2,:,:)-pimg(2,:,:)),inf)
Decomposition of high-frequency part...
scale = 5, Number of Tiles = 65
scale = 4, Number of Tiles = 33
scale = 3, Number of Tiles = 17
scale = 2, Number of Tiles = 9
scale = 1, Number of Tiles = 5
scale = 0, Number of Tiles = 3
scale = -1, Number of Tiles = 1
Decomposition of low frequency part...
Done!
ans =
4 8 65
Reconstruction from high-frequency part...
scale = 5, Number of Tiles = 65
scale = 4, Number of Tiles = 33
scale = 3, Number of Tiles = 17
scale = 2, Number of Tiles = 9
scale = 1, Number of Tiles = 5
scale = 0, Number of Tiles = 3
scale = -1, Number of Tiles = 1
Reconstrucion from low frequency part...
Done!
ans =
2 2049 513
ans =
2.0511e-009
ans =
1.4006e-009
See also
MEYER, BUMPV, NV, PARASCALE, WINDOWONPPGRID.
Copyright
Copyright (C) 2011. Xiaosheng Zhuang, University of Osnabrueck