fftfreqconvmx: Internal: Convert FFT frequency bins to Bark/Mel bins

In tuneR: Analysis of music and speech

Description

Generate a matrix of weights to combine FFT bins into Bark/Mel bins.

Usage

fft2barkmx(nfft, sr = 8000, nfilts = NULL, width = 1, minfreq = 0, 
    maxfreq = sr/2)
    
fft2melmx(nfft, sr = 8000, nfilts = 40, width = 1, minfreq = 0, 
    maxfreq = sr/2, htkmel = FALSE, constamp = FALSE)

Arguments

nfft	Source FFT size.
sr	Sampling rate of the signal.
nfilts	Number of desired output frequency bands. If NULL then one per Bark/Mel between minfreq and maxfreq.
width	Width of each output frequency band in Bark/Mel.
minfreq	Minimum frequency.
maxfreq	Maximum frequency.
htkmel	Use HTK- or Slaney's curve of the Melscale.
constamp	Make integration windows peak at 1 (constamp=TRUE) or sum to 1 (constamp=FALSE)

Value

wts	The weight matrix with 'nfft' columns and 'nfilts' rows.
binfreqs	Edge frequencies of the bins.

Note

While wts has nfft columns, the second half are all zero. Hence, Bark spectrum is fft2barkmx(nfft, sr) %*% abs(fft(xincols, nfft)).

Author(s)

Sebastian Krey [e-mail]

References

Daniel P. W. Ellis: http://www.ee.columbia.edu/~dpwe/resources/matlab/rastamat/, Malcolm Slaney: Auditory Toolbox http://cobweb.ecn.purdue.edu/~malcolm/interval/1998-010/

See Also

hz2bark, hz2mel

Examples

  #Mel matrix in Slaney's mfcc.m:
  #tuneR:::fft2melmx(512, 8000, 40, 1, 133.33, 6855.5, FALSE, FALSE)

Example output

tuneR documentation built on May 2, 2019, 6:15 p.m.