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Install the Fourier GIMP plug-in on Debian/Ubuntu

Fourier analysis can be used to identify and eliminate particular interfering features in an image. GIMP has a FFT plug-in for doing this but it's not packaged for Debian or Ubuntu and requires manual installation as outlined below.
From the author's website "A simple plug-in to do fourier transform on your image. The major advantage of this plugin is to be able to work with the transformed image inside GIMP. You can draw or apply filters in fourier space, and get the modified image with an inverse FFT".

Installing Gimp
Naturally you are required to have GIMP installed. This will be present on most desktop orientated distros already. But if not, install normally with apt:
apt-get install gimp

Getting some required packages
With GIMP installed there are a number of packages required to build the FFT plug-in. Firstly we require the gimptool utility packaged on Debian and Ubuntu as libgimp2.0-dev.
apt-get install libgimp2.0-dev
Secondly the we need the fftw Fourier Transform library, packaged on Debian and Ubuntu as libfftw3-dev.
apt-get install libfftw3-dev

Install the plug-in
The plug-in has to be installed from source. Simply download from the author's website then install as follows (changing the version numbers where necessary):
tar xvzf fourier-0.3.2.tar.gz cd fourier-0.3.2 make make install
If all has worked properly you should now have the options FFT Forward and FFT Inverse under the Filters > Generic menu within GIMP.

These instructions were tested on Debain 5.0(Lenny) and Ubuntu 8.10(Intrepid) with GIMP 2.6.*.
Compiling the plug-in in your home directory will be fine for single-user use but on a multi-user system you may with to do so elsewhere.
If compilation fails for the plug-in the error messages should allow you to identify whatever packages are required. The gimptool package should have most of the usual build tools as dependencies however.
Also usefull are the GAP plug-ins packaged as gimp-gap (Gimp Animation Package).

Fast Fourier transform at wikipedia
FFTW C subroutine library