wave_space_varThresh_inter
Purpose:
This WAIR command is used to obtain the wavelet space thresholded
representation of the volumetric data. This routine is employed
as an automatic shell command and does not require any user interaction,
as opposed to the corresponding wave_space_varThresh.
Usage:
wave_space_varThresh_inter
Num_Dims
x_1_Dim_Size
[ [x_k_Dim_Size] ]
noise_level
Thresh_Scheme
alpha
- where the following definitions are used:
-
- Num_Dims
- the number of dimensions of the data
- x_1_Dim_Size
- matrix-size of dimension 1
- x_k_Dim_Size
- matrix-size of dimensions 2 through Num_Dims
- noise_level
- the noise level (sigma) of the signals
- Thresh_Scheme
- the Wavelet-Space thresholding scheme: 1 is used for
simple thresholding at level alpha, see below, 2 is
used for Donoho-Johnston (DJ), and 3 for Dinov-Sumners (DS)
thresholding approaches, respectively
- alpha
- the thresholding level (for simple thresholding approach),
e.g., a thresholding level of alpha = 0.05 guarantees that only
the top 5% of the largest in magnitude wavelet coefficients pass
the filtering, all others are set to zero
Examples:
./wave_space_varThresh_inter ./WT_data.img ./WT_DS_data.img 3 256 256 256 10 3 0.0
- This will employ DS thresholding approach to analyze the data
"./WT_data.img" of dimensions 256x256y256z in wavelet space, assuming
random noise of level 10 has been convolved with the data.
The result will be saved as "./WT_DS_data.img".
© 1997 Ivo D. Dinov,
