pylops.signalprocessing.DWT2D¶
-
class
pylops.signalprocessing.
DWT2D
(dims, dirs=(0, 1), wavelet='haar', level=1, dtype='float64')[source]¶ Two dimensional Wavelet operator.
Apply 2D-Wavelet Transform along two directions
dirs
of a multi-dimensional array of sizedims
.Note that the Wavelet operator is an overload of the
pywt
implementation of the wavelet transform. Refer to https://pywavelets.readthedocs.io for a detailed description of the input parameters.Parameters: - dims :
tuple
Number of samples for each dimension
- dirs :
tuple
, optional Direction along which DWT2D is applied.
- wavelet :
str
, optional Name of wavelet type. Use
pywt.wavelist(kind='discrete')
for a list of available wavelets.- level :
int
, optional Number of scaling levels (must be >=0).
- dtype :
str
, optional Type of elements in input array.
Raises: - ModuleNotFoundError
If
pywt
is not installed- ValueError
If
wavelet
does not belong topywt.families
Notes
The Wavelet operator applies the 2-dimensional multilevel Discrete Wavelet Transform (DWT2) in forward mode and the 2-dimensional multilevel Inverse Discrete Wavelet Transform (IDWT2) in adjoint mode.
Attributes: Methods
__init__
(dims[, dirs, wavelet, level, dtype])Initialize this LinearOperator. adjoint
()Hermitian adjoint. apply_columns
(cols)Apply subset of columns of operator cond
([uselobpcg])Condition number of linear operator. conj
()Complex conjugate operator div
(y[, niter, densesolver])Solve the linear problem \(\mathbf{y}=\mathbf{A}\mathbf{x}\). dot
(x)Matrix-matrix or matrix-vector multiplication. eigs
([neigs, symmetric, niter, uselobpcg])Most significant eigenvalues of linear operator. matmat
(X)Matrix-matrix multiplication. matvec
(x)Matrix-vector multiplication. rmatmat
(X)Matrix-matrix multiplication. rmatvec
(x)Adjoint matrix-vector multiplication. todense
([backend])Return dense matrix. toimag
([forw, adj])Imag operator toreal
([forw, adj])Real operator tosparse
()Return sparse matrix. trace
([neval, method, backend])Trace of linear operator. transpose
()Transpose this linear operator. - dims :