FFTW" stands for "Fastest Fourier Transform in the West." FFTW is a C subroutine library for computing the discrete Fourier transform (DFT) in one or more dimensions, of arbitrary input size, and of both real and complex data, as well as of even/odd data, i.e., the discrete cosine/sine transforms, or DCT/DST.
FFTW’s speed is superior when compared to other publicly-available DFT programs and its performance is highly competitive with that of vendor-driven solutions. FFTW is also portable, so it will work well on most architectures without modification – something vendor-driven custom applications cannot match.
