dot-modulationSpectrum: Modulation spectrum per sound

In soundgen: Sound Synthesis and Acoustic Analysis

Modulation spectrum per sound

Description

Internal soundgen function.

Usage

.modulationSpectrum(
  audio,
  specSource = c("STFT", "audSpec")[1],
  windowLength = 15,
  step = 1,
  wn = "hanning",
  zp = 0,
  audSpec_pars = list(filterType = "butterworth", nFilters = 32, bandwidth = 1/24, yScale
    = "bark", dynamicRange = 120),
  msType = c("1D", "2D")[2],
  amRes = 5,
  maxDur = 5,
  specMethod = c("spec", "meanspec")[2],
  logSpec = FALSE,
  logMPS = FALSE,
  power = 1,
  normalize = TRUE,
  roughRange = c(30, 150),
  roughMean = NULL,
  roughSD = NULL,
  roughMinFreq = 1,
  amRange = c(10, 200),
  returnMS = TRUE,
  returnComplex = FALSE,
  plot = TRUE,
  savePlots = NULL,
  logWarpX = NULL,
  logWarpY = NULL,
  quantiles = c(0.5, 0.8, 0.9),
  kernelSize = 5,
  kernelSD = 0.5,
  colorTheme = c("bw", "seewave", "heat.colors", "...")[1],
  col = NULL,
  main = NULL,
  xlab = "Hz",
  ylab = "1/kHz",
  xlim = NULL,
  ylim = NULL,
  width = 900,
  height = 500,
  units = "px",
  res = NA,
  ...
)

Arguments

audio	a list returned by readAudio
specSource	'STFT' = Short-Time Fourier Transform; 'audSpec' = a bank of bandpass filters (see audSpectrogram)
windowLength, step, wn, zp	parameters for extracting a spectrogram if specType = 'STFT'. Window length and step are specified in ms (see spectrogram). If specType = 'audSpec', these settings have no effect
audSpec_pars	parameters for extracting an auditory spectrogram if specType = 'audSpec'. If specType = 'STFT', these settings have no effect
msType	'2D' = two-dimensional Fourier transform of a spectrogram; '1D' = separately calculated spectrum of each frequency band
amRes	target resolution of amplitude modulation, Hz. If NULL, the entire sound is analyzed at once, resulting in a single roughness value (unless it is longer than maxDur, in which case it is analyzed in chunks maxDur s long). If amRes is set, roughness is calculated for windows ~1000/amRes ms long (but at least 3 STFT frames). amRes also affects the amount of smoothing when calculating amMsFreq and amMsPurity
maxDur	sounds longer than maxDur s are split into fragments, and the modulation spectra of all fragments are averaged
specMethod	the function to call when calculating the spectrum of each frequency band (only used when msType = '1D'); 'meanspec' is faster and less noisy, whereas 'spec' produces higher resolution
logSpec	if TRUE, the spectrogram is log-transformed prior to taking 2D FFT
logMPS	if TRUE, the modulation spectrum is log-transformed prior to calculating roughness
power	raise modulation spectrum to this power (eg power = 2 for ^2, or "power spectrum")
normalize	if TRUE, the modulation spectrum of each analyzed fragment maxDur in duration is separately normalized to have max = 1
roughRange	the range of temporal modulation frequencies that constitute the "roughness" zone, Hz
roughMean, roughSD	the mean (Hz) and standard deviation (semitones) of a lognormal distribution used to weight roughness estimates. If either is null, roughness is calculated simply as the proportion of spectrum within roughRange. If both roughMean and roughRange are defined, weights outside roughRange are set to 0; a very large SD (a flat weighting function) gives the same result as just roughRange without any weighting (see examples)
roughMinFreq	frequencies below roughMinFreq (Hz) are ignored when calculating roughness (ie the estimated roughness increases if we disregard very low-frequency modulation, which is often strong)
amRange	the range of temporal modulation frequencies that we are interested in as "amplitude modulation" (AM), Hz
returnMS	if FALSE, only roughness is returned (much faster). Careful with exporting the modulation spectra of a lot of sounds at once as this requires a lot of RAM
returnComplex	if TRUE, returns a complex modulation spectrum (without normalization and warping)
plot	if TRUE, plots the modulation spectrum of each sound (see plotMS)
savePlots	if a valid path is specified, a plot is saved in this folder (defaults to NA)
logWarpX, logWarpY	numeric vector of length 2: c(sigma, base) of pseudolog-warping the modulation spectrum, as in function pseudo_log_trans() from the "scales" package
quantiles	labeled contour values, % (e.g., "50" marks regions that contain 50% of the sum total of the entire modulation spectrum)
kernelSize	the size of Gaussian kernel used for smoothing (1 = no smoothing)
kernelSD	the SD of Gaussian kernel used for smoothing, relative to its size
colorTheme	black and white ('bw'), as in seewave package ('seewave'), matlab-type palette ('matlab'), or any palette from palette such as 'heat.colors', 'cm.colors', etc
col	actual colors, eg rev(rainbow(100)) - see ?hcl.colors for colors in base R (overrides colorTheme)
xlab, ylab, main, xlim, ylim	graphical parameters
width, height, units, res	parameters passed to png if the plot is saved
...	other graphical parameters passed on to filled.contour.mod and contour (see spectrogram)

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