This function plots dynamically a sliding spectrum along a time wave. This basically corresponds to a short-term Fourier transform.
dynspec(wave, f, channel = 1, wl = 512, wn = "hanning", zp = 0,
ovlp = 0, fftw = FALSE, norm = FALSE, dB = NULL, dBref = NULL, plot = TRUE,
title = TRUE, osc = FALSE,
tlab = "Time (s)", flab = "Frequency (kHz)",
alab = "Amplitude", alim = NULL, flim = c(0, f/2000),
type = "l", from = NULL, to = NULL, envt = NULL,
msmooth = NULL, ksmooth = NULL, colspec = "black",
coltitle = "black", colbg = "white", colline = "black",
colaxis = "black", collab = "black", cexlab = 1,
fontlab = 1, colwave = "black",
coly0 = "lightgrey", colcursor = "red", bty = "l")an R object.
sampling frequency of wave (in Hz). Does not need to
be specified if embedded in wave.
channel of the R object, by default left channel (1).
if at is not null, length of the window for the analysis
(even number of points, by defaults = 512).
window name, see ftwindow (by default "hanning").
zero-padding (even number of points), see Details.
overlap between two successive windows (in % ).
if TRUE calls the function FFT of the
library fftw. See Notes of the spectro.
logical, if TRUE compute a normalised sliding spectrum.
a character string specifying the type dB to return: "max0" for a maximum dB value at 0, "A", "B", "C", "D", and "ITU" for common dB weights.
a dB reference value when dB is not NULL. NULL by default
but should be set to 2*10e-5 for a 20 microPa reference (SPL).
logical, if TRUE plots in an ew graphics device the successive
spectra sliding along the time wave (by default TRUE).
logical, if TRUE adds a title with the time position of the current
spectrum along the time wave.
logical, if TRUE plots an oscillogram beneath
the sliding spectrum with a cursor showing the position of the
current spectrum (by default FALSE).
title of the time axis.
title of the frequency axis.
title of the amplitude axis.
range of frequency axis.
range of amplitude axis.
type of plot that should be drawn for the sliding spectrum.
See plot for details (by default "l" for lines).
start mark where to compute the sliding spectrum (in s).
end mark where to compute the sliding spectrum (in s).
the type of envelope to be plooted:
either "abs" for absolute amplitude envelope or "hil" for Hilbert amplitude envelope.
See env.
when env is not NULL,
a vector of length 2 to smooth the amplitude envelope with a
mean sliding window. The first component is the window length
(in number of points). The second component is the overlap between
successive windows (in %). See env.
colour of the sliding spectrum.
if title is TRUE, colour of the title.
background colour.
colour of axes line.
colour of the axes.
colour of axes title.
character size for axes title.
font for axes title.
colour of the oscillogram or of the envelope (only when osc is TRUE).
colour of the y=0 line (only when osc is TRUE).
colour of oscillogram cursor (only when osc is TRUE).
the type of box to be drawn around the oscillogram (only
when osc is TRUE).
This function returns a list of three items:
a numeric vector corresponding to the time axis.
a numeric vector corresponding to the frequency axis.
a numeric matrix corresponding to the amplitude values.
Each column is a Fourier transform of length wl/2.
Use the slider panel to move along the time wave.
Use the argument norm if you wish to have each spectrum normalised, i.e.
with values between 0 and 1 or maximised to 0 dB when dB is TRUE.
The function requires the package rpanel that is based on the package tcltk.
spectro, spectro3D,
wf, spec, dynspectro,
fft, oscillo, env.
# NOT RUN {
data(sheep)
require(rpanel)
dynspec(sheep,f=8000,wl=1024,ovlp=50,osc=TRUE)
# }
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