Wavelet Toolbox |
Wavelet coefficient thresholding 2-D
Syntax
NC = wthcoef2('type
',C,S,N,T,SORH) NC = wthcoef2('type
',C,S,N) NC = wthcoef2('a',C,S) NC = wthcoef2('t',C,S,N,T,SORH)
Description
wthcoef2
is a two-dimensional de-noising and compression oriented function.
For 'type
' = 'h'
( 'v'
or 'd'
), NC = wthcoef2(
'type
',C,S,N,T,SORH)
returns the horizontal (vertical or diagonal, respectively) coefficients obtained from the wavelet decomposition structure [C,S]
(see wavedec2
for more information), by soft (if SORH
='s'
) or hard (if SORH
='h'
) thresholding defined in vectors N
and T
. N
contains the detail levels to be thresholded and T
the corresponding thresholds. N
and T
must be of the same length. The vector N
must be such that 1
N(i)
size(S,1)-2
.
For 'type
' = 'h'
('v'
or 'd'
), NC = wthcoef2(
'type
',C,S,N)
returns the horizontal (vertical or diagonal, respectively) coefficients obtained from [C,S]
by setting all the coefficients of detail levels defined in N
to zero.
NC = wthcoef2('a',C,S)
returns the coefficients obtained by setting approximation coefficients to zero.
NC = wthcoef2('t',C,S,N,T,SORH)
returns the detail coefficients obtained from the wavelet decomposition structure [C,S]
by soft (if SORH
='s'
) or hard (if SORH
='h'
) thresholding (see wthresh
for more information) defined in vectors N
and T
. N
contains the detail levels to be thresholded and T
the corresponding thresholds which are applied in the three detail orientations. N
and T
must be of the same length.
[NC,S]
is the modified wavelet decomposition structure.
wthcoef | wthresh |
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