High-level interface to FFTW (Fast Fourier Transform) based on comfort-array

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BSD-3-Clause licensed and maintained by Henning Thielemann
This version can be pinned in stack with:comfort-fftw-,3046

FFTW claims to be the fastest Fourier Transform in the West. This is a high-level interface to libfftw. We re-use the type classes from netlib-ffi.


  • Support of one (audio), two (image), three (video) dimensional data, as well as n-dimensional one.

  • Support for batched transformations e.g. for block-wise Fourier transform.

  • No normalization like in plain fftw. This is because I see no universally best place to apply normalization.

The use of comfort-array enables to use array shapes tailored to Fourier transforms:

for data where the n-1-th element can also be accessed via index -1.
for complex data of a real-to-complex Fourier transform. It saves you from case distinction between even and odd data length and according mistakes.
for real-to-real Sine and Cosine transforms. They assert that you will always use the appropriate kind for back transformation.

For rather simple examples see the packages align-audio and morbus-meniere.

See also package fft.