seewave (version 1.5.5)

wf: Waterfall display

Description

This function returns a waterfall display of a short-term Fourier transform or of any matrix.

Usage

wf(wave, f = NULL, wl = 512, zp = 0, ovlp = 0, dB = "max0", dBref = NULL, wn = "hanning", 
x = NULL, hoff = 1, voff = 1, col = heat.colors,
xlab = "Frequency (kHz)", ylab = "Amplitude (dB)", xaxis = TRUE, yaxis =
TRUE, density = NULL, border = NULL, lines = FALSE, ...)

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

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

zp

zero-padding (even number of points), see Details.

ovlp

overlap between two successive windows (in %).

dB

a character string specifying the type dB to return: "max0" for a maximum dB value at 0, "A", "B", "C" and "D" for common dB weights.

dBref

a dB reference value when dB is TRUE. NULL by default but should be set to 2*10e-5 for a 20 microPa reference.

wn

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

x

a matrix if wave is not provided.

hoff

horizontal 'offset' which shifts actual x-values slightly per row for visibility. Fractional parts will be removed.

voff

vertical 'offset' which separates traces.

col

a color or a color palette function to be used to assign colors in the plot

xlab

title of the frequency x-axis.

ylab

title of the amplitude y-axis.

xaxis

a logical, if TRUE adds the frequency x-axis according to f.

yaxis

a logical, if TRUE adds the amplitude y-axis according.

density

argument of polygon: the density of shading lines, in lines per inch. The default value of 'NULL' means that no shading lines are drawn. A zero value of 'density' mean

border

argument of polygon: the color to draw the border. The default, 'NULL', means to use 'par("fg")'. Use 'border = NA' to omit borders.

lines

a logical, if TRUE plots lines instead of surfaces (polygons).

...

other graphical arguments to passed to plot

Details

Data input can be either a time wave (wave) or a matrix (x). In that case, if xaxis is set to TRUE the x-axis will follow the row index. To change it, turn xaxis to FALSE and use axis afterwards. See examples.

See Also

spectro, spectro3D, dynspec

Examples

data(tico)
wf(tico,f=22050)
# changing the display parameters
jet.colors <- colorRampPalette(c("blue", "green"))
wf(tico,f=22050, hoff=0, voff=2, col=jet.colors, border = NA)
# matrix input instead of a time wave and transparent lines display
m <- numeric()
for(i in seq(-pi,pi,len=40)) {m <- cbind(m,10*(sin(seq(0,2*pi,len=100)+i)))}
wf(x=m, lines=TRUE, col="#0000FF50",xlab="Time", ylab="Amplitude",
main="waterfall display")