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 . |
'sqtwolog uwn' |
See 'sqtwolog ' option in thselect , and see also wden when used with 'sln ' option. |
'sqtwolog swn' |
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 | ![]() |