.getRMS: RMS amplitude per sound

Description

Internal soundgen function called by getRMS.

Usage

.getRMS(
  audio,
  windowLength = 50,
  step = NULL,
  overlap = 75,
  stereo = c("left", "right", "average", "both")[1],
  killDC = FALSE,
  normalize = TRUE,
  windowDC = 200,
  plot = TRUE,
  main = NULL,
  xlab = "",
  ylab = "",
  type = "b",
  col = "green",
  lwd = 2,
  width = 900,
  height = 500,
  units = "px",
  res = NA,
  ...
)

Arguments

audio: a list returned by readAudio
windowLength: length of FFT window, ms (multiple values in a vector produce a multi-resolution spectrogram)
step: you can override overlap by specifying FFT step, ms - a vector of the same length as windowLength (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, %
stereo: 'left' = only left channel, 'right' = only right channel, 'average' = take the mean of the two channels, 'both' = return RMS for both channels separately
killDC: if TRUE, removed DC offset (see also flatEnv)
normalize: if TRUE, the RMS amplitude is returned as proportion of the maximum possible amplitude as given by scale
windowDC: the window for calculating DC offset, ms
plot: if TRUE, plot a contour of RMS amplitude
xlab, ylab, main: general graphical parameters
type, col, lwd: graphical parameters pertaining to the RMS envelope
width, height, units, res: graphical parameters for saving plots passed to png
...: other graphical parameters