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ISIS Documentation

ifft

Apply an Inverse Fourier Transform on a magnitude/phase pair of cubes

This program accepts two cubes, most likely acquired from the fft program, containing the magnitude and phase angle data of a Fourier transformed image and returns the inverse.

The output cube will contain an AlphaCube group if the input cube to the fft program contained one. For exmaple, if a cube was cropped and then run through the fft program, the output cube from this program will contain the original AlphaCube group.

Categories

Related Objects and Documents

Applications

History

Jacob Danton2005-11-28 Original version
Brendan George2006-09-28 Documentation fixes
Steven Lambright2008-05-12 Removed references to CubeInfo
Steven Lambright2008-10-16 Fixed documentation: example GUI screenshots were missing, they should now exist. The name of the GUI screenshot was incorrect, "fft" was changed to "ifft."
Steven Lambright2012-02-24 This program now takes advantage of multiple global processing threads.
Ian Humphrey2017-08-19 Now removes the AlphaCube group from the output cube if the fft input cube did not have an AlphaCube group. Fixes #4907.

Parameters

Files

The input cube containing the image magnitude data.
Type cube
File Mode input
Filter *.cub

The input cube containing the image phase angle data.
Type cube
File Mode input
Filter *.cub

The result of the inverse transform.
Type cube
File Mode output
Filter *.cub

Example 1

ifft example

Example of the inverse Fourier transform.

Command Line

Compute the inverse Fourier transform of peaks_magnitude.cub and peaks_phase.cub and store the result in peaks.cub .
ifft magnitude=peaks_magnitude.cub phase=peaks_phase.cub to=peaks.cub

GUI Screenshot

ifft GUI

Example GUI

ifft GUI

Screenshot of GUI with parameters filled in to perform the ifft application

Input Images

Magnitude image

Example magnitude output

Magnitude image

Parameter Name: MAGNITUDE

This is the magnitude output of the transform of peaks.cub.

Phase image

Example phase output

Phase image

Parameter Name: PHASE

This is the phase output of the transform of peaks.cub.

Output Image

Output image

Example output

Output image

Parameter Name: FROM

This is the output image, peaks.cub.