dot-segment: Internal soundgen function

In soundgen: Sound Synthesis and Acoustic Analysis

Internal soundgen function

Description

A helper function called internally by segment() for segmenting a single sound.

Usage

.segment(
  audio,
  shortestSyl = 40,
  shortestPause = 40,
  method = c("env", "spec", "mel")[3],
  propNoise = NULL,
  SNR = NULL,
  noiseLevelStabWeight = c(1, 0.25),
  windowLength = 40,
  step = NULL,
  overlap = 80,
  reverbPars = list(reverbDelay = 70, reverbSpread = 130, reverbLevel = -35,
    reverbDensity = 50),
  interburst = NULL,
  peakToTrough = SNR + 3,
  troughLocation = c("left", "right", "both", "either")[4],
  maxDur = 30,
  saveAudio = NULL,
  addSilence = 50,
  plot = FALSE,
  plotname = "",
  savePlots = NULL,
  main = NULL,
  xlab = "",
  ylab = "Signal, dB",
  showLegend = FALSE,
  width = 900,
  height = 500,
  units = "px",
  res = NA,
  maxPoints = c(1e+05, 5e+05),
  specPlot = NULL,
  contourPlot = list(lty = 1, lwd = 2, col = "green"),
  sylPlot = list(lty = 1, lwd = 2, col = "blue"),
  burstPlot = list(pch = 8, cex = 3, col = "red"),
  ...
)

Arguments

audio	a list returned by readAudio
shortestSyl	minimum acceptable length of syllables, ms
shortestPause	minimum acceptable break between syllables, ms (syllables separated by shorter pauses are merged)
method	the signal used to search for syllables: 'env' = Hilbert-transformed amplitude envelope, 'spec' = spectrogram, 'mel' = mel-transformed spectrogram (see tuneR::melfcc)
propNoise	the proportion of non-zero sound assumed to represent background noise, 0 to 1 (note that complete silence is not considered, so padding with silence won't affect the algorithm)
SNR	expected signal-to-noise ratio (dB above noise), which determines the threshold for syllable detection. The meaning of "dB" here is approximate since the "signal" may be different from sound intensity
noiseLevelStabWeight	a vector of length 2 specifying the relative weights of the overall signal level vs. stability when attempting to automatically locate the regions that represent noise. Increasing the weight of stability tends to accentuate the beginning and end of each syllable.
windowLength	length of FFT window, ms
step	you can override overlap by specifying FFT step, ms (NB: because digital audio is sampled at discrete time intervals of 1/samplingRate, the actual step and thus the time stamps of STFT frames may be slightly different, eg 24.98866 instead of 25.0 ms)
overlap	overlap between successive FFT frames, %
reverbPars	parameters passed on to reverb to attempt to cancel the effects of reverberation or echo, which otherwise tend to merge short and loud segments like rapid barks
interburst	minimum time between two consecutive bursts (ms). Defaults to the average detected (syllable + pause) / 2
peakToTrough	to qualify as a burst, a local maximum has to be at least peakToTrough dB above the left and/or right local trough(s) (controlled by troughLocation) over the analysis window (controlled by interburst). Defaults to SNR + 3 dB
troughLocation	should local maxima be compared to the trough on the left and/or right of it? Values: 'left', 'right', 'both', 'either'
maxDur	long files are split into chunks maxDur s in duration to avoid running out of RAM; the outputs for all fragments are glued together, but plotting is switched off. Note that noise profile is estimated in each chunk separately, so set it low if the background noise is highly variable
saveAudio	full path to the folder in which to save audio files (one per detected syllable)
addSilence	if syllables are saved as separate audio files, they can be padded with some silence (ms)
plot	if TRUE, produces a segmentation plot
savePlots	full path to the folder in which to save the plots (NULL = don't save, ” = same folder as audio)
xlab, ylab, main	main plotting parameters
showLegend	if TRUE, shows a legend for thresholds
width, height, units, res	parameters passed to png if the plot is saved
maxPoints	the maximum number of "pixels" in the oscillogram (if any) and spectrogram; good for quickly plotting long audio files; defaults to c(1e5, 5e5)
specPlot	a list of graphical parameters for displaying the spectrogram (if method = 'spec' or 'mel'); set to NULL to hide the spectrogram
contourPlot	a list of graphical parameters for displaying the signal contour used to detect syllables (see details)
sylPlot	a list of graphical parameters for displaying the syllables
burstPlot	a list of graphical parameters for displaying the bursts
...	other graphical parameters passed to graphics::plot

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