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Streaming algorithms

FFTWC

Inputs

  • frame (vector_complex) - the input frame (complex)

Outputs

  • fft (vector_complex) - the FFT of the input frame

Parameters

  • size (integer ∈ [1, ∞), default = 1024) :

    the expected size of the input frame. This is purely optional and only targeted at optimizing the creation time of the FFT object

Description

This algorithm computes the positive complex STFT (Short-term Fourier transform) of an array of Reals using the FFT algorithm. The resulting fft has a size of (s/2)+1, where s is the size of the input frame. At the moment FFT can only be computed on frames which size is even and non zero, otherwise an exception is thrown.

References:

[1] Fast Fourier transform - Wikipedia, the free encyclopedia, http://en.wikipedia.org/wiki/Fft

[2] Fast Fourier Transform -- from Wolfram MathWorld, http://mathworld.wolfram.com/FastFourierTransform.html

Universitat Pompeu Fabra - Music Technology Group