pylops.signalprocessing.Sliding2D

pylops.signalprocessing.Sliding2D(Op, dims, dimsd, nwin, nover, tapertype='hanning', design=False)[source]

2D Sliding transform operator.

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 2-dimensional arrays in nature as they are internally reshaped and interpreted as 2-dimensional arrays. Each patch contains in fact a portion of the array in the first dimension (and the entire second dimension).

This operator can be used to perform local, overlapping transforms (e.g., pylops.signalprocessing.FFT2 or pylops.signalprocessing.Radon2D) of 2-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 use design=True if unsure about the choice dims and use the number of windows printed on screen to define such input parameter.

Parameters:
Op : pylops.LinearOperator

Transform operator

dims : tuple

Shape of 2-dimensional model. Note that dims[0] should be multiple of the model size of the transform in the first dimension

dimsd : tuple

Shape of 2-dimensional data

nwin : int

Number of samples of window

nover : int

Number of samples of overlapping part of window

tapertype : str, optional

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

design : bool, optional

Print number of sliding window (True) or not (False)
Returns:
Sop : pylops.LinearOperator

Sliding operator
Raises:
ValueError

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

Examples using pylops.signalprocessing.Sliding2D