FF: Estimation of Fundamental Frequencies from a Wspec object

Description

Estimation of Fundamental Frequencies from an object of class Wspec. Additionally, some heuristics are used to distinguish silence, noise (and breathing for singers) from real tones.

Usage

FF(object, peakheight = 0.01, silence = 0.2, minpeak = 9, diapason = 440, 
    notes = NULL, interest.frqs = seq(along = object@freq),
    search.par = c(0.8, 10, 1.3, 1.7))
    
FFpure(object, peakheight = 0.01, diapason = 440, 
    notes = NULL, interest.frqs = seq(along = object@freq),
    search.par = c(0.8, 10, 1.3, 1.7))

Arguments

object

An object of class Wspec.

peakheight

The peak's proportion of the maximal peak height to be considered for fundamental frequency detection. The default (0.01) means peaks smaller than 0.02 times the maximal peak height are omitted.

silence

The maximum proportion of periodograms to be considered as silence or noise (such as breathing). The default (0.2) means that less than 20 out of 100 periodograms represent silence or noise.

minpeak

If more than minpeak peaks are considered for detection and passed argument peakheight, such periodograms are detected to be silence or noise (if silence > 0).

diapason

Frequency of diapason a, default is 440 (Hertz).

notes

Optional, a vector of integers indicating the notes (in halftones from diapason a) that are expected. By applying this restriction, the detection error might be reduced in some cases.

interest.frqs

Optional, either a vector of integers indicating the indices of (fundamental) frequencies in object that are expected, or one of the character strings "bass", "tenor", "alto" or "sop

search.par

Parameters to look for peaks:

The first peak larger thanpeakheight * 'largest_peak'is taken.
Its frequency is multiplied by1+search.par[1]Now, any larger peak between the old peak and that value is taken,

Value

Vector of estimated fundamental frequencies (in Hertz) for each periodogram conatined in object.

concept

pitch
fundamental
frequency
tracking
f0
periodogram
Wave

Details

FFpure just estimates the fundamental frequencies for all periodograms contained in the object (of class Wspec. FF additionally uses some heuristics to distinguish silence, noise (and breathing for singers) from real tones. It is recommended to use the wrapper function FF rather than FFpure. If silence detecion can be omitted by specifying silence = 0.