seewave (version 1.5.2)

dfreq: Dominant frequency of a time wave

Description

This function gives the dominant frequency (i. e. the frequency of highest amplitude) of a time wave.

Usage

dfreq(wave, f, wl = 512, wn = "hanning", ovlp = 0, threshold = NULL,
plot = TRUE, xlab = "Times (s)", ylab = "Frequency (kHz)",
ylim = c(0, f/2000), type ="l",...)

Arguments

wave

a vector, a matrix (first column), an object of class ts, Sample (left channel), or Wave (left channel).

f

sampling frequency of wave (in Hz). Does not need to be specified if wave is an object of class ts, Sample, or Wave

wl

length of the window for the analysis (even number of points, by default = 512).

wn

window name, see ftwindow (by default "hanning").

ovlp

overlap between two successive analysis windows (in % ).

threshold

amplitude threshold for signal detection (in % ).

plot

logical, if TRUE plots the dominant frequency against time (by default TRUE).

xlab

title of the x axis.

ylab

title of the y axis.

ylim

the range of y values.

type

if plot is TRUE, type of plot that should be drawn. See plot for details (by default "l" for lines).

...

other plot graphical parameters.

Value

• When plot is FALSE, dfreq returns a two-column matrix, the first column corresponding to time in seconds (x-axis) and the second column corresponding to to dominant frequency in kHz (y-axis). NA corresponds to pause sections in wave (see threshold).

See Also

spec, meanspec,spectro.

Examples

data(tico)
dfreq(tico,f=22050,ovlp=50,threshold=5)
# overlay on spectrogram
spectro(tico,f=22050,ovlp=50,zp=16,scale=FALSE,
    collevels=seq(-40,0,1),palette=rev.terrain.colors)
par(new=TRUE,las=1)
dfreq(tico,f=22050,ovlp=50,threshold=6,col="red",lwd=2,
    ann=FALSE)