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/* -*-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 Mdct{

  int n;
  int log2n;

  float[] trig;
  int[] bitrev;

  float scale;

  void init(int n){
    bitrev=new int[n/4];
    trig=new float[n+n/4];

    log2n=(int)Math.rint(Math.log(n)/Math.log(2));
    this.n=n;

    int AE=0;
    int AO=1;
    int BE=AE+n/2;
    int BO=BE+1;
    int CE=BE+n/2;
    int CO=CE+1;
    // trig lookups...
    for(int i=0; i>>j!=0; j++)
          if(((msb>>>j)&i)!=0)
            acc|=1<>>1;
    int n4=n>>>2;
    int n8=n>>>3;

    // rotate + step 1
    {
      int inO=1;
      int xO=0;
      int A=n2;

      int i;
      for(i=0; i>>(i+2);
        int k1=1<<(i+3);
        int wbase=n2-2;

        A=0;
        float[] temp;

        for(int r=0; r<(k0>>>2); r++){
          int w1=wbase;
          w2=w1-(k0>>1);
          float AEv=trig[A], wA;
          float AOv=trig[A+1], wB;
          wbase-=2;

          k0++;
          for(int s=0; s<(2<