Class Lpc


  • public class Lpc
    extends java.lang.Object
    LPC - and Reflection Coefficients.

    The next two functions calculate linear prediction coefficients and/or the related reflection coefficients from the first P_MAX+1 values of the autocorrelation function.

    Invented by N. Levinson in 1947, modified by J. Durbin in 1959.

    Version:
    $Revision: 1.2 $
    Author:
    Marc Gimpel, Wimba S.A. (mgimpel@horizonwimba.com)
    • Constructor Summary

      Constructors 
      Constructor Description
      Lpc()  
    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static void autocorr​(float[] x, float[] ac, int lag, int n)
      Compute the autocorrelation ,--, ac(i) = > x(n) * x(n-i) for all n `--' for lags between 0 and lag-1, and x == 0 outside 0...n-1
      static float wld​(float[] lpc, float[] ac, float[] ref, int p)
      Returns minimum mean square error.
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Constructor Detail

      • Lpc

        public Lpc()
    • Method Detail

      • wld

        public static float wld​(float[] lpc,
                                float[] ac,
                                float[] ref,
                                int p)
        Returns minimum mean square error.
        Parameters:
        lpc - - float[0...p-1] LPC coefficients
        ac - - in: float[0...p] autocorrelation values
        ref - - out: float[0...p-1] reflection coef's
        p -
        Returns:
        minimum mean square error.
      • autocorr

        public static void autocorr​(float[] x,
                                    float[] ac,
                                    int lag,
                                    int n)
        Compute the autocorrelation ,--, ac(i) = > x(n) * x(n-i) for all n `--' for lags between 0 and lag-1, and x == 0 outside 0...n-1
        Parameters:
        x - - in: float[0...n-1] samples x
        ac - - out: float[0...lag-1] ac values
        lag -
        n -