A UGen that performs a constant Q spectral analysis, using an already FFT'ed input signal.
For each input window, the output signal consists of numBands
filter output values.
These values are '''squared''', since further processing might need to decimate them again
or take the logarithm. Otherwise the caller needs to add .sqrt
to get the actual filter outputs.
The default settings specify a range of nine octaves and numBands = 432
thus being 48 bands
per octave. At 44.1 kHz, the default minimum frequency would be 35.28 Hz, the maximum would be
18063.36 Hz.
- Value parameters:
- fftSize
the fft size which corresponds with the window size of the input
- in
the input signal which has already been windowed and FFT'ed using
Real1FFT
in mode 0 or 2. The windows should have been rotated prior to the FFT so that the time signal starts in the middle of the window and then wraps around.- maxFreqN
the normalized maximum frequency (frequency in Hz, divided by the sampling rate). should be greater than zero and less than or equal to 0.5.
- minFreqN
the normalized minimum frequency (frequency in Hz, divided by the sampling rate). should be greater than zero and less than or equal to 0.5.
- numBands
the number of bands or kernels to apply, spreading them evenly (logarithmically) across the range from minimum to maximum frequency.
- Companion:
- object