| Wavelet Toolbox | ![]() |
Syntax
Description
THR = wthrmngr(OPTION,METHOD,VARARGIN) returns a global threshold or level dependent thresholds depending on OPTION. The inputs, VARARGIN, depend on the OPTION and METHOD values.
This M-file returns the thresholds used throughout the MATLAB Wavelet Toolbox for de-noising and compression tools (command line M-files or GUI tools).
Valid options for the METHOD parameter are listed in the table below.
METHOD |
Description |
'scarcehi' |
See wdcbm or wdcbm2 when used with 'high' predefined value of parameter M. |
'scarceme' |
See wdcbm or wdcbm2 when used with 'medium' predefined value of parameter M. |
'scarcelo' |
See wdcbm or wdcbm2 when used with 'low' predefined value of parameter M. |
'sqtwolog' |
See 'sqtwolog' option in thselect, and see also wden. |
'sqtwologuwn' |
See 'sqtwolog' option in thselect, and see also wden when used with 'sln' option. |
'sqtwologswn' |
See 'sqtwolog' option in thselect, and see also wden when used with 'mln' option. |
'rigsure' |
See 'rigsure' option in thselect, and see also wden. |
'heursure' |
See 'heursure' option in thselect, and see also wden. |
'minimaxi' |
See 'minimaxi' option in thselect, and see also wden. |
'penalhi' |
See wbmpen or wpbmpen when used with 'high' value of parameter ALPHA. |
'penalme' |
See wbmpen or wpbmpen when used with 'medium' value of parameter ALPHA. |
'penallo' |
See wbmpen or wpbmpen when used with 'low' value of parameter ALPHA. |
'rem_n0' |
This option returns a threshold close to 0. A typical THR value is median(abs(coefficients)). |
'bal_sn' |
This option returns a threshold such that the percentages of retained energy and number of zeros are the same. |
'sqrtbal_sn' |
This option returns a threshold equal to the square root of the value such that the percentages of retained energy and number of zeros are the same. |
Discrete Wavelet 1-D Options
Compression using a global threshold.. X is the signal to be compressed and [C,L] is the wavelet decomposition structure of the signal to be compressed.
THR = wthrmngr('dw1dcompGBL','rem_n0',X)
THR = wthrmngr('dw1dcompGBL','bal_sn',X)
Compression using level dependent thresholds.. X is the signal to be compressed and [C,L] is the wavelet decomposition structure of the signal to be compressed.
ALFA is a sparsity parameter (see wdcbm for more information).
THR = wthrmngr('dw1dcompLVL','scarcehi',C,L,ALFA)
ALFA must be such that 2.5 < ALFA < 10
THR = wthrmngr('dw1dcompLVL','scarceme',C,L,ALFA)
ALFA must be such that 1.5 < ALFA < 2.5
THR = wthrmngr('dw1dcompLVL','scarcelo',C,L,ALFA)
ALFA must be such that 1 < ALFA < 2
De-noising using level dependent thresholds.. [C,L] is the wavelet decomposition structure of the signal to be de-noised, SCAL defines the multiplicative threshold rescaling (see wden for more information) and ALFA is a sparsity parameter (see wbmpen for more information).
THR = wthrmngr('dw1ddenoLVL','sqtwolog',C,L,SCAL)
THR = wthrmngr('dw1ddenoLVL','rigrsure',C,L,SCAL)
THR = wthrmngr('dw1ddenoLVL','heursure',C,L,SCAL)
THR = wthrmngr('dw1ddenoLVL','minimaxi',C,L,SCAL)
THR = wthrmngr('dw1ddenoLVL','penalhi',C,L,ALFA)
ALFA must be such that 2.5 < ALFA < 10
THR = wthrmngr('dw1ddenoLVL','penalme',C,L,ALFA)
ALFA must be such that 1.5 < ALFA < 2.5
THR = wthrmngr('dw1ddenoLVL','penallo',C,L,ALFA)
ALFA must be such that 1 < ALFA < 2
Discrete Stationary Wavelet 1-D Options
De-noising using level dependent thresholds.. SWTDEC is the stationary wavelet decomposition structure of the signal to be de-noised, SCAL defines the multiplicative threshold rescaling (see wden for more information) and ALFA is a sparsity parameter (see wbmpen for more information).
THR = wthrmngr('sw1ddenoLVL',METHOD,SWTDEC,SCAL)
THR = wthrmngr('sw1ddenoLVL',METHOD,SWTDEC,ALFA)
The options for METHOD are the same as in the 'dw1ddenoLVL'case.
Discrete Wavelet 2-D Options
Compression using a global threshold.. X is the image to be compressed and [C,S] is the wavelet decomposition structure of the image to be compressed.
THR = wthrmngr('dw2dcompGBL','rem_n0',X)
THR = wthrmngr('dw2dcompGBL','bal_sn',C,S)
THR = wthrmngr('dw2dcompGBL','sqrtbal_sn',C,S)
Compression using level dependent thresholds.. X is the image to be compressed and [C,S] is the wavelet decomposition structure of the image to be compressed. ALFA is a sparsity parameter (see wdcbm2 for more information).
THR = wthrmngr('dw2dcompLVL','scarcehi',C,L,ALFA)
ALFA must be such that 2.5 < ALFA < 10
THR = wthrmngr('dw2dcompLVL','scarceme',C,L,ALFA)
ALFA must be such that 1.5 < ALFA < 2.5
THR = wthrmngr('dw2dcompLVL','scarcelo',C,L,ALFA)
ALFA must be such that 1 < ALFA < 2
De-noising using level dependent thresholds.. [C,S] is the wavelet decomposition structure of the image to be de-noised, SCAL defines the multiplicative threshold rescaling (see wden for more information) and ALFA is a sparsity parameter (see wbmpen for more information).
THR = wthrmngr('dw2ddenoLVL','penalhi',C,S,ALFA)
ALFA must be such that 2.5 < ALFA < 10
THR = wthrmngr('dw2ddenoLVL','penalme',C,L,ALFA)
ALFA must be such that 1.5 < ALFA < 2.5
THR = wthrmngr('dw2ddenoLVL','penallo',C,L,ALFA)
ALFA must be such that 1 < ALFA < 2
THR = wthrmngr('dw2ddenoLVL','sqtwolog',C,S,SCAL)
THR = wthrmngr('dw2ddenoLVL','sqrtbal_sn',C,S)
Discrete Stationary Wavelet 2-D Options
De-noising using level dependent thresholds.. SWTDEC is the stationary wavelet decomposition structure of the image to be de-noised, SCAL defines the multiplicative threshold rescaling (see wden for more information) and ALFA is a sparsity parameter (see wbmpen for more information).
THR = wthrmngr('sw2ddenoLVL',METHOD,SWTDEC,SCAL)
THR = wthrmngr('sw2ddenoLVL',METHOD,SWTDEC,ALFA)
The options for METHOD are the same as in the 'dw2ddenoLVL' case.
Discrete Wavelet Packet 1-D Options
Compression using a global threshold.. X is the signal to be compressed and WPT is the wavelet packet decomposition structure of the signal to be compressed.
THR = wthrmngr('wp1dcompGBL','bal_sn',WPT)
THR = wthrmngr('wp1dcompGBL','rem_n0',X)
De-noising using a global threshold.. WPT is the wavelet packet decomposition structure of the signal to be de-noised.
THR = wthrmngr('wp1ddenoGBL','sqtwologuwn',WPT)
THR = wthrmngr('wp1ddenoGBL','sqtwologswn',WPT)
THR = wthrmngr('wp1ddenoGBL','bal_sn',WPT)
THR = wthrmngr('wp1ddenoGBL','penalhi',WPT)
see wbmpen with ALFA = 6.25
THR = wthrmngr('wp1ddenoGBL','penalme',WPT)
see wbmpen with ALFA = 2
THR = wthrmngr('wp1ddenoGBL','penallo',WPT)
see wbmpen with ALFA = 1.5
Discrete Wavelet Packet 2-D Options
Compression using a global threshold.. X is the image to be compressed and WPT is the wavelet packet decomposition structure of the image to be compressed.
THR = wthrmngr('wp2dcompGBL','bal_sn',WPT)
THR = wthrmngr('wp2dcompGBL','rem_n0',X)
THR = wthrmngr('wp2dcompGBL','sqrtbal_sn',WPT)
De-noising using a global threshold.. WPT is the wavelet packet decomposition structure of the image to be de-noised.
THR = wthrmngr('wp2ddenoGBL','sqtwologuwn',WPT)
THR = wthrmngr('wp2ddenoGBL','sqtwologswn',WPT)
THR = wthrmngr('wp2ddenoGBL','sqrtbal_sn',WPT)
THR = wthrmngr('wp2ddenoGBL','penalhi',WPT)
see wbmpen with ALFA = 6.25
THR = wthrmngr('wp2ddenoGBL','penalme',WPT)
see wbmpen with ALFA = 2
THR = wthrmngr('wp2ddenoGBL','penallo',WPT)
see wbmpen with ALFA = 1.5
| wthresh | wtreemgr | ![]() |