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, Sample = FALSE,...)

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).
listen if TRUE the new sound is played back.
Sample if TRUE and plot is FALSE returns an object of class Sample
... 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 as a one-column matrix or as a Sample object if Sample is TRUE.

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 1.5.0 Index]