pylops.signalprocessing.Sliding3D

pylops.signalprocessing.Sliding3D(Op, dims, dimsd, nwin, nover, nop, tapertype='hanning', nproc=1, name='S')[source]

3D Sliding transform operator.w

Apply a transform operator Op repeatedly to patches of the model vector in forward mode and patches of the data vector in adjoint mode. More specifically, in forward mode the model vector is divided into patches each patch is transformed, and patches are then recombined in a sliding window fashion. Both model and data should be 3-dimensional arrays in nature as they are internally reshaped and interpreted as 3-dimensional arrays. Each patch contains in fact a portion of the array in the first and second dimensions (and the entire third dimension).

This operator can be used to perform local, overlapping transforms (e.g., pylops.signalprocessing.FFTND or pylops.signalprocessing.Radon3D) of 3-dimensional arrays.

Note

The shape of the model has to be consistent with the number of windows for this operator not to return an error. As the number of windows depends directly on the choice of nwin and nover, it is recommended to first run sliding3d_design to obtain the corresponding dims and number of windows.

Warning

Depending on the choice of nwin and nover as well as the size of the data, sliding windows may not cover the entire data. The start and end indices of each window will be displayed and returned with running sliding3d_design.

Parameters:
Op : pylops.LinearOperator

Transform operator

dims : tuple

Shape of 3-dimensional model. Note that dims[0] and dims[1] should be multiple of the model sizes of the transform in the first and second dimensions

dimsd : tuple

Shape of 3-dimensional data

nwin : tuple

Number of samples of window

nover : tuple

Number of samples of overlapping part of window

nop : tuple

Number of samples in axes of transformed domain associated to spatial axes in the data

tapertype : str, optional

Type of taper (hanning, cosine, cosinesquare or None)

nproc : int, optional

Number of processes used to evaluate the N operators in parallel using multiprocessing. If nproc=1, work in serial mode.

name : str, optional

New in version 2.0.0.

Name of operator (to be used by pylops.utils.describe.describe)

Returns:
Sop : pylops.LinearOperator

Sliding operator

Raises:
ValueError

Identified number of windows is not consistent with provided model shape (dims).

Examples using pylops.signalprocessing.Sliding3D