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Etyl's default sound module

There is a newer version: 1.2.0

/* -*-mode:java; c-basic-offset:2; indent-tabs-mode:nil -*- */
/* JOrbis
 * Copyright (C) 2000 ymnk, JCraft,Inc.
 *  
 * Written by: 2000 ymnk
 *   
 * Many thanks to 
 *   Monty  and 
 *   The XIPHOPHORUS Company http://www.xiph.org/ .
 * JOrbis has been based on their awesome works, Vorbis codec.
 *   
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public License
 * as published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
   
 * This program 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 Library General Public License for more details.
 * 
 * You should have received a copy of the GNU Library General Public
 * License along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

package com.jcraft.jorbis;

class Lpc{
  // en/decode lookups
  Drft fft=new Drft();;

  int ln;
  int m;

  // Autocorrelation LPC coeff generation algorithm invented by
  // N. Levinson in 1947, modified by J. Durbin in 1959.

  // Input : n elements of time doamin data
  // Output: m lpc coefficients, excitation energy

  static float lpc_from_data(float[] data, float[] lpc, int n, int m){
    float[] aut=new float[m+1];
    float error;
    int i, j;

    // autocorrelation, p+1 lag coefficients

    j=m+1;
    while(j--!=0){
      float d=0;
      for(i=j; i