plotMS: Plot modulation spectrum

In soundgen: Sound Synthesis and Acoustic Analysis

Plot modulation spectrum

Description

Plots a single modulation spectrum returned by modulationSpectrum. The result is the same as the plot produced by modulationSpectrum, but calling plotMS is handy for processed modulation spectra - for instance, for plotting the difference between the modulation spectra of two sounds or groups of sounds.

Usage

plotMS(
  ms,
  X = as.numeric(colnames(ms)),
  Y = as.numeric(rownames(ms)),
  quantiles = c(0.5, 0.8, 0.9),
  colorTheme = "bw",
  col = NULL,
  logWarpX = NULL,
  logWarpY = NULL,
  main = NULL,
  xlab = "Hz",
  ylab = "1/kHz",
  xlim = NULL,
  ylim = NULL,
  audio = NULL,
  extraY = TRUE,
  ...
)

Arguments

ms	modulation spectrum - a matrix with temporal modulation in columns and spectral modulation in rows, as returned by modulationSpectrum
X, Y	colnames and rownames of ms, respectively
quantiles	numeric vector of cumulative contours in (0, 1). For example, 0.5 marks a region that contains 50% of the total modulation-spectrum amplitude. Set to NULL to omit contour lines
colorTheme	plot color theme
col	custom color palette; if supplied, overrides colorTheme
logWarpX, logWarpY	numeric vector of length 2: c(sigma, base) for pseudolog-warping the modulation spectrum in the plot, as in pseudo_log_trans() from the scales package. These arguments affect plotting only; the returned matrices are not log-warped
main, xlab, ylab, xlim, ylim	graphical parameters
audio	(internal) a list of audio attributes
extraY	if TRUE, another Y-axis is plotted on the right showing 1 / (Y-axis value) as a frequency in Hz (assuming that ms is derived from an ordinary STFT with linearly spaced frequency bins)
...	other graphical parameters passed on to filled.contour.mod and contour (see spectrogram)

Value

Does not return anything, just plots the MS.

Examples

ms1 = modulationSpectrum(runif(4000), samplingRate = 16000, plot = TRUE)
plotMS(ms1$detailed$processed)  # identical to above

# compare two modulation spectra
ms2 = modulationSpectrum(soundgen(sylLen = 100, addSilence = 0),
                         samplingRate = 16000)
# ensure the two matrices have the same dimensions
ms2_resized = soundgen:::interpolMatrix(ms2$detailed$original,
  nr = nrow(ms1$detailed$original), nc = ncol(ms1$detailed$original))
# plot the difference
plotMS(log(ms1$detailed$original / ms2_resized), quantiles = NULL,
  col = colorRampPalette(c('blue', 'yellow')) (50))

soundgen documentation built on Sept. 20, 2026, 5:07 p.m.