Visualize_FFT

fourier_transform

Purpose

This utility allows you to visualize the Fourier Transform of an image, volume or set of images and volumes. The output is a real space image or volume as only the phase or amplitudes are shown.

Usage

$ fourier_tranform ...

Parameters

• __OR__ Visualize the Fourier Transform of a single file

• __OR__ If no output file is given, then the input one is rewritten

• `` Visualize the Fourier Transform of a bunch of files

• __OR__ If no output extension neither root are given, then the input ones are rewritten

• `` Do not produce on screen information

• `` Return the phase of the Fourier transform

• `` Return the amplitudes of the Fourier transform

• `` Return thelog10 of the result (amplitudes or phase). This option is usually used with`-squared` and`-amplitudes` because the extremely wide range of amplitude values

• `` Return the squared (²) value of the result (amplitudes or phase)

• `` By default, the result is shown in such a way that thefrequency0= is in the middle of the image or volume. Using this option the result reflects the Fourier transform in the same way as Xmipp understands it internally

Examples and Notes

Looking at the amplitude of the Fourier transform

$ fourier_tranform -i g0ta00001.xmp -o g0ta00001_ampl.xmp -amplitudes -log10 -squared

Looking at the phase of the Fourier transform

$ fourier_transform -i g0ta00001.xmp -o g0ta00001_phase.xmp -phase

--Main.AlfredoSolano - 22 Jan 2007