Wavelet coefficient thresholding 2-D
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)
wthcoef2 is a two-dimensional
de-noising and compression oriented function.
For 'type' = 'h' ( 'v' or 'd'), NC
= wthcoef2( returns
the horizontal (vertical or diagonal, respectively) coefficients obtained
from the wavelet decomposition structure 'type',C,S,N,T,SORH)[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( returns
the horizontal (vertical or diagonal, respectively) coefficients obtained
from 'type',C,S,N)[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.