Mammut is a program for Linux, Windows Mac OS X that does audio processing in the frequency domain.
Mammut does an FFT of the whole sound (no windows). Various operations can subsequently be done in the frequency domain, such as unlinear stretching of the spectrum, sprectrum shifting, etc.
Doing a giant FFT of the entire sound, as opposed to splitting the sound up into short windows, is unusual. Such a method implies that time-related parameters are included in the spectral coefficients in a non-intuitive manner, and changes in the frequency domain may radically change developments in the time domain.
Mammut is a fairly unpredictable program, and the user will need to get used to letting go of controlling the time axis. The sounding results are often surprising and exciting.
However, Mammut is also ideal for more normal operations such as filtering, spectrum shifting and convolution. With no windows, the sound quality is optimal.
Mammut uses a standard radix-2 FFT, but the number of points in the analysis is typically several million, and not just a few thousand which one is used to from short FFTs.
The signal processing algorithms in Mammut is mainly designed and programmed by Øyvind Hammer, while the user interface is designed by Kjetil Matheussen.