dynspec: Dynamic sliding spectrum

In seewave: Sound Analysis and Synthesis

Dynamic sliding spectrum

Description

This function plots dynamically a sliding spectrum along a time wave. This basically corresponds to a short-term Fourier transform.

Usage

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")

Arguments

wave	an R object.
f	sampling frequency of wave (in Hz). Does not need to be specified if embedded in wave.
channel	channel of the R object, by default left channel (1).
wl	if at is not null, length of the window for the analysis (even number of points, by defaults = 512).
wn	window name, see ftwindow (by default "hanning").
zp	zero-padding (even number of points), see Details.
ovlp	overlap between two successive windows (in % ).
fftw	if TRUE calls the function FFT of the library fftw. See Notes of the spectro.
norm	logical, if TRUE compute a normalised sliding spectrum.
dB	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.
dBref	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).
plot	logical, if TRUE plots in an ew graphics device the successive spectra sliding along the time wave (by default TRUE).
title	logical, if TRUE adds a title with the time position of the current spectrum along the time wave.
osc	logical, if TRUE plots an oscillogram beneath the sliding spectrum with a cursor showing the position of the current spectrum (by default FALSE).
tlab	title of the time axis.
flab	title of the frequency axis.
alab	title of the amplitude axis.
flim	range of frequency axis.
alim	range of amplitude axis.
type	type of plot that should be drawn for the sliding spectrum. See plot for details (by default "l" for lines).
from	start mark where to compute the sliding spectrum (in s).
to	end mark where to compute the sliding spectrum (in s).
envt	the type of envelope to be plooted: either "abs" for absolute amplitude envelope or "hil" for Hilbert amplitude envelope. See env.
msmooth	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.
ksmooth	when env is not NULL, kernel smooth via kernel. See env.
colspec	colour of the sliding spectrum.
coltitle	if title is TRUE, colour of the title.
colbg	background colour.
colline	colour of axes line.
colaxis	colour of the axes.
collab	colour of axes title.
cexlab	character size for axes title.
fontlab	font for axes title.
colwave	colour of the oscillogram or of the envelope (only when osc is TRUE).
coly0	colour of the y=0 line (only when osc is TRUE).
colcursor	colour of oscillogram cursor (only when osc is TRUE).
bty	the type of box to be drawn around the oscillogram (only when osc is TRUE).

Details

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.

Value

This function returns a list of three items:

time	a numeric vector corresponding to the time axis.
freq	a numeric vector corresponding to the frequency axis.
amp	a numeric matrix corresponding to the amplitude values. Each column is a Fourier transform of length wl/2.

Note

This function is very similar to a spectrogram. See the Details of spectro for some information regarding the short term Fourier transform.

Author(s)

Jerome Sueur and Caroline Simonis

See Also

spectro, spectro3D, wf, spec, dynspectro, fft, oscillo, env.

Examples

## Not run: 
data(sheep)
require(rpanel)
dynspec(sheep,f=8000,wl=1024,ovlp=50,osc=TRUE)

## End(Not run)

seewave documentation built on Oct. 19, 2023, 5:07 p.m.