快速傅里叶变换
Pd's native objects range from the basic mathematical, logical, and bitwise operators found in every programming language to general and specialized audio-rate DSP functions (designated by a tilde (~) symbol), such as wavetable oscillators, the Fast Fourier transform (fft~), and a range of standard filters. Data can be loaded from file, read in from an audio board, MIDI, via Open Sound Control (OSC) through a FireWire, USB, or network connection, or generated on the fly, and stored in tables, which can then be read back and used as audio signals or control data.