cLpc

Description

This component computes linear predictive coding (LPC) coefficients from PCM frames. Burg's algorithm and the standard ACF/Durbin based method are implemented for LPC coefficient computation. The output of LPC filter coefficients, reflection coefficients, residual signal, and LP spectrum is supported.

Type hierarchy

cDataProcessorcVectorProcessorcLpc

Fields

  • method (string) [default: acf]

    This option sets the lpc method to use. Choose between: 'acf' acf (autocorrelation) method with Levinson-Durbin algorithm , 'burg' Burg method (N. Anderson (1978))

  • p (numeric) [default: 8.0]

    Predictor order (= number of lpc coefficients)

  • saveLPCoeff (numeric) [default: 1.0]

    1 = save LP coefficients to output

  • lpGain (numeric) [default: 0.0]

    1 = save lpc gain (error) in output vector

  • saveRefCoeff (numeric) [default: 0.0]

    1 = save reflection coefficients to output

  • residual (numeric) [default: 0.0]

    1 = compute lpc residual signal and store in output frame

  • residualGainScale (numeric) [default: 0.0]

    1 = scale lpc residual signal by lpc gain (divides each frame by gain)

  • forwardFilter (numeric) [default: 0.0]

    1 = apply forward instead of inverse filter when computing residual

  • lpSpectrum (numeric) [default: 0.0]

    1 = compute lp spectrum using 'lpSpecDeltaF' as frequency resolution or 'lpSpecBins' bins

  • forwardLPspec (numeric) [default: 1.0]

    1 = compute forward filter transfer function as LP spectrum, instead of old default behaviour of computing spectrum of inverse filter.

  • forwardLPspecFloor (numeric) [default: 1e-13]

    Floor value to add to all spectral bins of inverse LP spectrum when inverting the spectrum (1/x) to avoid division by 0. Default: 10^-13.

  • lpSpecDeltaF (numeric) [default: 10.0]

    frequency resolution of lp spectrum (only applicable if 'lpSpectrum=1')

  • lpSpecBins (numeric) [default: 100.0]

    number of bins to compute lp spectrum for (overrides lpSpecDeltaF) (only applicable if 'lpSpectrum=1')