getVocalFry: Subharmonics
In tatters/soundgen_beta: Parametric Voice Synthesis

Description Usage Arguments Details Value Examples

Internal soundgen function.

1 2	getVocalFry(rolloff, pitch_per_gc, subFreq = 100, subDep = 100, throwaway = -120, shortestEpoch = 300)

`rolloff`	matrix of original amplitudes of each harmonic in f0 stack returned by `getRolloff` (columns=time, rows=frequency bins)
`pitch_per_gc`	vector of the same length as ncol(rolloff)): f0 in Hz, one value per glottal cycle
`subFreq`	target frequency of subharmonics, Hz (lower than f0, adjusted dynamically so f0 is always a multiple of subFreq)
`subDep`	the width of subharmonic band, Hz. Regulates how quickly the strength of subharmonics fades as they move away from harmonics in f0 stack. Low values produce narrow sidebands, high values produce uniformly strong subharmonics
`throwaway`	discard harmonics and noise that are quieter than this number (in dB, defaults to -120) to save computational resources
`shortestEpoch`	minimum duration of each epoch with unchanging subharmonics regime, in ms

Adds subharmonics to the main (f0) harmonic stack, forming sidebands.

Returns a list consisting of a list of rolloff matrices (one matrix per epoch) and a dataframe of epochs.

pitch_per_gc = c(400, 500, 600, 700)
rolloff = getRolloff(pitch_per_gc, rolloff = -30)
# one epoch, two subharmonics
rolloff_subh = soundgen:::getVocalFry(rolloff, pitch_per_gc,
  subFreq = 200, subDep = 150, shortestEpoch = 100)
# three epochs with 2/3/4 subharmonics
rolloff_subh = soundgen:::getVocalFry(rolloff, pitch_per_gc,
  subFreq = 200, subDep = 150, shortestEpoch = 0)