Inverse discrete stationary wavelet transform 1-D
uses the scaling filter
x = iswt(
LoR and wavelet filter
HiR. The filters are expected to be the reconstruction
filters associated with the wavelet used to create the
structure. For more information, see
iswt(swa(end,:),swd,LoR,HiR) is equivalent to
Demonstrate perfect reconstruction using
iswt with a biorthogonal wavelet.
load noisbloc [Lo_D,Hi_D,Lo_R,Hi_R] = wfilters('bior3.5'); [swa,swd] = swt(noisbloc,3,Lo_D,Hi_D); recon = iswt(swa,swd,Lo_R,Hi_R); norm(noisbloc-recon)
ans = 1.0818e-13
swc— Multilevel stationary wavelet decomposition
Multilevel stationary wavelet decomposition, specified as a real-valued
swc is the output of
Wavelet, specified as a character vector or string scalar.
iswt supports only Type 1 (orthogonal) or Type 2
(biorthogonal) wavelets. See
wfilters for a list of
orthogonal and biorthogonal wavelets.
swa— Approximation coefficients
Approximation coefficients, specified as a real-valued matrix.
swa is the output of
swd— Detail coefficients
Detail coefficients, specified as a real-valued matrix.
swd is the output of
LoR,HiR— Wavelet reconstruction filters
Wavelet reconstruction filters, specified as a pair of even-length
LoR is the scaling (lowpass)
reconstruction filter, and
HiR is the wavelet (highpass)
reconstruction filter. The lengths of
HiR must be equal. See
wfilters for additional
 Nason, G. P., and B. W. Silverman. “The Stationary Wavelet Transform and Some Statistical Applications.” In Wavelets and Statistics, edited by Anestis Antoniadis and Georges Oppenheim, 103:281–99. New York, NY: Springer New York, 1995. https://doi.org/10.1007/978-1-4612-2544-7_17.
 Coifman, R. R., and D. L. Donoho. “Translation-Invariant De-Noising.” In Wavelets and Statistics, edited by Anestis Antoniadis and Georges Oppenheim, 103:125–50. New York, NY: Springer New York, 1995. https://doi.org/10.1007/978-1-4612-2544-7_9.
 Pesquet, J.-C., H. Krim, and H. Carfantan. “Time-Invariant Orthonormal Wavelet Representations.” IEEE Transactions on Signal Processing 44, no. 8 (August 1996): 1964–70. https://doi.org/10.1109/78.533717.
Usage notes and limitations:
wname must be constant.