KISS FFT - A mixed-radix Fast Fourier Transform

There are many great fft libraries already around. Kiss FFT is not trying
to be better than any of them. It only attempts to be a reasonably efficient,
moderately useful FFT that can use fixed or floating data types and can be
incorporated into someone's C program in a few minutes with trivial licensing.

Homepage:
https://github.com/mborgerding/kissfft
