org.xiph.speex

Class Lsp

java.lang.Object

org.xiph.speex.Lsp

public class Lsp
extends java.lang.Object

Line Spectral Pair

Version:

$Revision: 1.2 $

Author:

Jim Lawrence, helloNetwork.com, Marc Gimpel, Wimba S.A. (mgimpel@horizonwimba.com)

Field Summary

Fields

Modifier and Type	Field and Description
private float[]	pw

Constructor Summary

Constructors

Constructor and Description
Lsp() Constructor

Method Summary

Modifier and Type	Method and Description
static float	cheb_poly_eva(float[] coef, float x, int m) This function evaluates a series of Chebyshev polynomials.
static void	enforce_margin(float[] lsp, int len, float margin) Makes sure the LSPs are stable.
static int	lpc2lsp(float[] a, int lpcrdr, float[] freq, int nb, float delta) This function converts LPC coefficients to LSP coefficients.
void	lsp2lpc(float[] freq, float[] ak, int lpcrdr) Line Spectral Pair to Linear Prediction Coefficients

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

pw

private float[] pw

Constructor Detail

Lsp

public Lsp()

Constructor

Method Detail

cheb_poly_eva

public static final float cheb_poly_eva(float[] coef,
                                        float x,
                                        int m)

This function evaluates a series of Chebyshev polynomials.

Parameters:

coef - - coefficients of the polynomial to be evaluated.

x - - the point where polynomial is to be evaluated.

m - - order of the polynomial.

Returns:

the value of the polynomial at point x.

lpc2lsp

public static int lpc2lsp(float[] a,
                          int lpcrdr,
                          float[] freq,
                          int nb,
                          float delta)

This function converts LPC coefficients to LSP coefficients.

Parameters:

a - - LPC coefficients.

lpcrdr - - order of LPC coefficients (10).

freq - - LSP frequencies in the x domain.

nb - - number of sub-intervals (4).

delta - - grid spacing interval (0.02).

Returns:

the number of roots (the LSP coefs are returned in the array).

lsp2lpc

public void lsp2lpc(float[] freq,
                    float[] ak,
                    int lpcrdr)

Line Spectral Pair to Linear Prediction Coefficients

Parameters:

freq -

ak -

lpcrdr -

enforce_margin

public static void enforce_margin(float[] lsp,
                                  int len,
                                  float margin)

Makes sure the LSPs are stable.

Parameters:

lsp -

len -

margin -