Tutorials and Topics - Peabody Computer Music

Tutorial 26Frequency domain signalprocessing using pfft~The pfft~ object takes as its argument the name of a specially designed subpatchcontaining the fftin~ and fftout~ objects (which will be discussed below), a number for theFFT size in samples, and a number for the overlap factor (these must both be integerswhich are a power of 2):A simple use of pfft~.The pfft~ subpatch fftbasic~ referenced above might look something like this:The fftbasic~ subpatch used in the previous exampleThe fftbasic~ subpatch shown above takes a signal input, performs an FFT on that signalwith a Hanning window (see below), and performs an IFFT on the FFT’d signal, also witha Hanning window. The pfft~ object communicates with its sub-patch using specialobjects for inlets and outlets. The fftin~ object receives a time-domain signal from itsparent patch and transforms it via an FFT into the frequency domain. This time-domain204