FourierFilter

class hcipy.fourier.FourierFilter(input_grid, transfer_function, q=1)

Bases: object

A filter in the Fourier domain.

The filtering is performed by Fast Fourier Transforms, but is quicker than the equivalent multiplication in the Fourier domain using the FastFourierTransform classes. It does this by avoiding redundant field multiplications that limit performance.

Parameters:
input_gridGrid

The grid that is expected for the input field.

transfer_functionField generator or Field

The transfer function to use for the filter. If this is a Field, the user is responsible for checking that its grid corresponds to the internal grid used by this filter. The Grid is not checked.

qscalar

The amount of zeropadding to perform in the real domain. A value of 1 denotes no zeropadding. Zeropadding increases the resolution in the Fourier domain and therefore reduces aliasing/wrapping effects.

Methods Summary

backward(field)

Return the backward (adjoint) filtering of the input field.

forward(field)

Return the forward filtering of the input field.

Methods Documentation

backward(field)

Return the backward (adjoint) filtering of the input field.

Parameters:
fieldField

The field to filter.

Returns:
Field

The adjoint filtered field.

forward(field)

Return the forward filtering of the input field.

Parameters:
fieldField

The field to filter.

Returns:
Field

The filtered field.