afilter {seewave}R Documentation

Amplitude filter

Description

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

Usage

afilter(wave, f, threshold = 5, plot = TRUE,
listen = FALSE, output = "matrix", ...)

Arguments

wave an R object.
f sampling frequency of wave (in Hz). Does not need to be specified if embedded in wave.
threshold amplitude threshold (in %).
plot logical, if TRUE plots the new oscillogram (by default TRUE).
listen if TRUE the new sound is played back.
output character string, the class of the object to return, either "matrix", "Wave", "Sample", "audioSample" or "ts".
... other oscillo graphical parameters.

Details

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

Value

If plot is FALSE, a new wave is returned. The class of the returned object is set with the argument output.

Note

This function is used as an argument (threshold) in the following functions: autoc, csh, dfreq, timer and zc.

Author(s)

Jerome Sueur sueur@mnhn.fr

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)

[Package seewave version 1.5.6 Index]