R: Amplitude filter

afilter {seewave}

R Documentation

Amplitude filter

Description

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

Usage

afilter(wave, f, channel = 1, 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`.
`channel`	channel of the R object, by default left channel (1).
`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

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 2.1.6 Index]