fma: Frequency modulation analysis

In seewave: Sound Analysis and Synthesis

Frequency modulation analysis

Description

This function computes the Fourier analysis of the instantaneous frequency of a time wave. This allows to detect periodicity in frequency modulation.

Usage

fma(wave, f, channel = 1, threshold = NULL, plot = TRUE, ...)

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 for signal detection (in % ).
plot	logical, if TRUE the spectrum of the instantaneous frequency (by default TRUE).
...	other spec parameters.

Details

This function is based on ifreq and spec.
The instantaneous frequency of wave is first computed and the spectrum of this frequency modulation is then processed. All env and spec arguments can be set up.

Value

If plot is FALSE, fma returns a numeric vector corresponding to the computed spectrum. If peaks is not NULL, fma returns a list with two elements:

spec	the spectrum computed
peaks	the peaks values (in kHz).

Author(s)

Jerome Sueur [e-mail]

See Also

ifreq, hilbert, spec, ama

Examples

# a sound with a 1 kHz sinusoid FM
a<-synth(d=1, f=8000, cf=1500, fm=c(1000,1000,0,0,0), output="Wave")
fma(a)

seewave documentation built on Oct. 19, 2023, 5:07 p.m.