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FFT

pre 1.18

Perform fourier transform on number array.



Node Data

ValuesAnimationArrayArray

Display name

FFT

Internal name

Node_FFT

Inheritances

node
node_processor
node_fft

Inputs

node_fft

float

Data

enum

Preprocess Function

Outputs

node_fft

float

Array

Fourier transformation is a process that convert series of data from time domain to frequency domain.



Data Domain


The domain describe what the x-axis represent. Array of audio data is by default in the time domain, which means each number describe the amplitude of the audio at a specific time.

After the Fourier transformation, the data is converted to frequency domain, the value now represent the amplitude of the audio at a specific frequency.




Fourier Transform


Fourier transform is a function that takes series of data in time domain and converting it to frequency domain. The formula for Fourier transform is:


$$X(f) = \int_{-\infty}^{\infty} x(t) \cdot e^{-i2\pi ft} dt$$


This may look intimidating, and it's kinda is. If you want an intuitive description please watch 3Blue1Brown video on Fourier transform here:




FFT node used an optimized version for discrete fourier Transform calls fast fourier transform. Again I'd recommend a video by Reducible on FFT which explains it way better that I could ever have done here: