generateEpoch: Generate an epoch

In soundgen: Sound Synthesis and Acoustic Analysis

Generate an epoch

Description

Internal soundgen function. Takes descriptives of a number of glottal cycles (f0, closed phase, rolloff) and creates a continuous waveform. The principle is to work with one epoch with stable regime of subharmonics at a time and create a sine wave for each harmonic, with amplitudes adjusted by rolloff.

Usage

generateEpoch(pitch_per_gc, epochs, rolloff_per_epoch, samplingRate)

Arguments

pitch_per_gc	pitch per glottal cycle, Hz
epochs	a dataframe specifying the beginning and end of each epoch
rolloff_per_epoch	a list of matrices with one matrix for each epoch; each matrix should contain one column for each glottal cycle and one row for each harmonic (linear multiplier, ie NOT in dB). Rownames specify the ratio to F0 (eg 1.5 means it's a subharmonic added between f0 and its first harmonic)
samplingRate	the sampling rate of generated sound, Hz

Value

Returns a waveform as a non-normalized numeric vector centered at zero.

Examples

pitch_per_gc = seq(100, 150, length.out = 90)
epochs = data.frame (start = c(1, 51),
                     end = c(50, 90))
m1 = matrix(rep(10 ^ (-6 * log2(1:200) / 20), 50), ncol = 50, byrow = FALSE)
m2 = matrix(rep(10 ^ (-12 * log2(1:200) / 20), 40), ncol = 40, byrow = FALSE)
rownames(m1) = 1:nrow(m1)
rownames(m2) = 1:nrow(m2)
rolloff_source = list(m1, m2)
s = soundgen:::generateEpoch(pitch_per_gc, epochs,
                             rolloff_source, samplingRate = 16000)
# plot(s, type = 'l')
# playme(s)

soundgen documentation built on Sept. 12, 2024, 6:29 a.m.