seewave (version 1.4.3)

afilter: Amplitude filter

Description

This function deletes all signal which amplitude is below a selected threshold.

Usage

afilter(wave, f, threshold = 5, plot = TRUE, ...)

Arguments

wave

data describing the time wave or a Sample object generated loading a wav file with loadSample (package Sound).

f

sampling frequency of wave (in Hz). Does not need to be specified if wave is a Sample object.

threshold

amplitude threshold (in %).

plot

logical, if TRUE plots the new oscillogram (by default TRUE).

...

other oscillo graphical parameters.

Value

• If plot is FALSE, afilter returns a one column matrix with the new wave.

Details

The threshold value is in % relative to the maximal value of wave. Signal inferior to this value is clipped.

See Also

ffilter, oscillo

Examples

data(orni)
op<-par(mfrow=c(2,1))
afilter(orni,f=22050)
title(main = "threshold level = 5")
afilter(orni,f=22050,threshold=0.5,colwave="blue")
title(main = "threshold level = 0.5")
par(op)