lpcfunc.h File Reference

Implementation of linear prediction functions, and conversion between common representations of linear predictive parameters. More...

#include <itpp/base/vec.h>
#include <itpp/itexports.h>

Go to the source code of this file.

Namespaces
namespace	itpp
	itpp namespace

Functions
ITPP_EXPORT vec	itpp::chirp (const vec &a, double factor)
	Returns a chirped version of the input vector.
ITPP_EXPORT double	itpp::sd (const vec &In1, const vec &In2)
	Spectral distortion between two vectors, in dB.
ITPP_EXPORT double	itpp::sd (const vec &In1, const vec &In2, double highestfreq)
	Spectral distortion between two vectors, in dB, up to highest frequency highestfreq.
ITPP_EXPORT vec	itpp::lerouxguegenrc (const vec &R, int order)
	Computes reflection coefficients from autocorrelation, using the Le-Roux-Guegen algorithm.
ITPP_EXPORT vec	itpp::levinson (const vec &R2, int order)
	Levinson - Levinson-Durbin recursion.
ITPP_EXPORT vec	itpp::autocorr (const vec &x, int order)
	Computes the autocorrelation function.
ITPP_EXPORT vec	itpp::lpc (const vec &x, int order)
	lpc - Linear Predictive Coefficients using autocorrelation method.
ITPP_EXPORT vec	itpp::schurrc (const vec &R, int order)
	schurrc - Schur algorithm.
ITPP_EXPORT vec	itpp::ac2rc (const vec &ac)
	ac2rc - Autocorrelation sequence to reflection coefficients conversion.
ITPP_EXPORT vec	itpp::ac2poly (const vec &ac)
	ac2poly - Autocorrelation sequence to prediction polynomial conversion.
ITPP_EXPORT vec	itpp::is2rc (const vec &is)
	is2rc - Inverse sine parameters to reflection coefficients conversion.
ITPP_EXPORT vec	itpp::lar2rc (const vec &lar)
	lar2rc - Log area ratios to reflection coefficients conversion.
ITPP_EXPORT vec	itpp::lsf2poly (const vec &lsf)
	lsf2poly - Line spectral frequencies to prediction polynomial conversion.
ITPP_EXPORT vec	itpp::poly2ac (const vec &poly)
	poly2ac - Prediction polynomial to autocorrelation sequence conversion.
ITPP_EXPORT vec	itpp::poly2lsf (const vec &poly)
	poly2lsf - Prediction polynomial to line spectral frequencies conversion.
ITPP_EXPORT vec	itpp::poly2rc (const vec &poly)
	poly2rc - Prediction polynomial to reflection coefficients conversion.
ITPP_EXPORT vec	itpp::poly2cepstrum (const vec &a)
	poly2cepstrum - Prediction polynomial to cepstrum conversion.
ITPP_EXPORT vec	itpp::poly2cepstrum (const vec &a, int num)
	poly2cepstrum - Prediction polynomial to cepstrum conversion, to the specified order.
ITPP_EXPORT vec	itpp::cepstrum2poly (const vec &c)
	cepstrum2poly - Cepstrum to prediction polynomial conversion.
ITPP_EXPORT vec	itpp::rc2ac (const vec &rc)
	rc2ac - Reflection coefficients to autocorrelation sequence conversion.
ITPP_EXPORT vec	itpp::rc2is (const vec &rc)
	rc2is - Reflection coefficients to inverse sine parameters conversion.
ITPP_EXPORT vec	itpp::rc2lar (const vec &rc)
	rc2lar - Reflection coefficients to log area ratios conversion.
ITPP_EXPORT vec	itpp::rc2poly (const vec &rc)
	rc2poly - Reflection coefficients to prediction polynomial conversion.

Detailed Description

Implementation of linear prediction functions, and conversion between common representations of linear predictive parameters.

Author

Thomas Eriksson

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Copyright (C) 1995-2010 (see AUTHORS file for a list of contributors)

This file is part of IT++ - a C++ library of mathematical, signal processing, speech processing, and communications classes and functions.

IT++ is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

IT++ is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with IT++. If not, see http://www.gnu.org/licenses/.

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Here we define functions for linear predictive analysis and coding. Several functions for computation of lpc parameters are given, together with functions to convert between various common representations of the lpc polynomial coefficients. The functionality is the same as in the MATLAB functions with the same names.

The short term for the various parameter types are: poly - LPC polynomial coefficients ac - autocorrelation coefficients rc - reflection coefficients lar - log area ratios is - inverse sine parameters lsf - line spectral frequencies

Definition in file lpcfunc.h.