# fftin~

## Description

The fftin~ object provides an signal input to a patcher loaded by a pfft~ object.

## Examples

## Discussion

Where the pfft~ object manages the windowing and overlap of the incoming signal, fftin~ applies the windowing function (the envelope) and performs the Fast Fourier Transform.

## Arguments

### inlet-assignment [int]

Determines the inlet number of the pfft~ which will be routed into the fftin~ object. Inlet assignment starts at one, for the leftmost inlet in the pfft~. Multiple fftin~ objects will typically have different inlet numbers.

### window-envelope-function [symbol]

Specifies the window envelope function the fftin~ object will apply to overlapping FFTs on the input signal. The options are (i.e. no window envelope), (the default), , and (Note: The Blackman window should be used with an overlap of 4 or more). If the symbol is used, then the fftin~ object will not use a windowing envelope and will not perform a Fast Fourier Transform -- it will echo the first half of its input sample window to its real output and the second half of its input sample window to its imaginary output. This can allow you to input raw control signals from outside the parent patcher through inlets in the pfft~ object, provided its overlap is set to 2. Other overlap values may not yield useful results.

## Attributes

### Common Box Attributes

## Messages

## Output

### signal

Out left outlet: This output contains the real-values resulting from the Fast Fourier transform performed on the corresponding inlet of the pfft~. This output frame is only half the size of the parent pfft~ object's FFT size because the spectrum of a real input signal is symmetrical and therefore half of it is redundant. The real and imaginary pairs for one spectrum are called a spectral frame.

Out middle outlet: This output contains the imaginary-values resulting from the Fast Fourier transform performed on the corresponding inlet of the pfft~. This output frame is only half the size of the parent pfft~ object's FFT size because the spectrum of a real input signal is symmetrical and therefore half of it is redundant. The real and imaginary pairs for one spectrum are called a spectral frame.

Out right outlet: A stream of samples corresponding to the index of the current bin whose data is being sent out the first two outlets. This is a number from 0 - (frame size - 1). The spectral frame size inside a pfft~ object's subpatch is equal to half the FFT window size.

## See Also

Name | Description |
---|---|

Spectral Processing | Spectral Processing |

Sound Processing Techniques | Sound Processing Techniques |

cartopol | |

cartopol~ | |

fft~ | |

fftinfo~ | |

fftout~ | |

frameaccum~ | |

framedelta~ | |

ifft~ | |

in | |

out | |

pfft~ | |

poltocar | |

poltocar~ | |

vectral~ | |

MSP Analysis Tutorial 4: Signal Processing with pfft~ | MSP Analysis Tutorial 4: Signal Processing with pfft~ |