ConstantQ
streaming mode | Standard category
Inputs
- frame (vector_real) - the windowed input audio frame
Outputs
- constantq (vector_complex) - the Constant Q transform
Parameters
- binsPerOctave (integer ∈ [1, ∞), default = 12) :
- number of bins per octave
- minFrequency (real ∈ [1, ∞), default = 32.7) :
- minimum frequency [Hz]
- minimumKernelSize (integer ∈ [2, ∞), default = 4) :
- minimum size allowed for frequency kernels
- numberBins (integer ∈ [1, ∞), default = 84) :
- number of frequency bins, starting at minFrequency
- sampleRate (real ∈ [0, ∞), default = 44100) :
- FFT sampling rate [Hz]
- scale (real ∈ [0, ∞), default = 1) :
- filters scale. Larger values use longer windows
- threshold (real ∈ [0, 1), default = 0.01) :
- bins whose magnitude is below this quantile are discarded
- windowType (string ∈ {hamming, hann, hannnsgcq, triangular, square, blackmanharris62, blackmanharris70, blackmanharris74, blackmanharris92}, default = hann) :
- the window type
- zeroPhase (bool ∈ {true, false}, default = true) :
- a boolean value that enables zero-phase windowing. Input audio frames should be windowed with the same phase mode
Description
This algorithm computes Constant Q Transform using the FFT for fast calculation. It transforms a windowed audio frame into the log frequency domain.
- References:
- [1] Constant Q transform - Wikipedia, the free encyclopedia, https://en.wikipedia.org/wiki/Constant_Q_transform [2] Brown, J. C., & Puckette, M. S. (1992). An efficient algorithm for the calculation of a constant Q transform. The Journal of the Acoustical Society of America, 92(5), 2698-2701. [3] Schörkhuber, C., & Klapuri, A. (2010). Constant-Q transform toolbox for music processing. In 7th Sound and Music Computing Conference, Barcelona, Spain (pp. 3-64).
See also
ConstantQ (standard) FFT (standard) FFT (streaming)