#ifdef HAVEMPGLIB/* * Mpeg Layer-1,2,3 audio decoder * ------------------------------ * copyright (c) 1995,1996,1997 by Michael Hipp, All rights reserved. * See also 'README' * * slighlty optimized for machines without autoincrement/decrement. * The performance is highly compiler dependend. Maybe * the decode.c version for 'normal' processor may be faster * even for Intel processors. */#include <stdlib.h>#if defined(__riscos__) && defined(FPA10)#include	"ymath.h"#else#include	<math.h>#endif#include <string.h>#include "mpg123.h"#include "mpglib.h"extern struct mpstr *gmp; /* old WRITE_SAMPLE */#define WRITE_SAMPLE(samples,sum,clip) \  if( (sum) > 32767.0) { *(samples) = 0x7fff; (clip)++; } \  else if( (sum) < -32768.0) { *(samples) = -0x8000; (clip)++; } \  else { *(samples) = ((sum)>0 ? (sum)+0.5 : (sum)-0.5) ; }int synth_1to1_mono(real *bandPtr,unsigned char *samples,int *pnt){  short samples_tmp[64];  short *tmp1 = samples_tmp;  int i,ret;  int pnt1 = 0;  ret = synth_1to1(bandPtr,0,(unsigned char *) samples_tmp,&pnt1);  samples += *pnt;  for(i=0;i<32;i++) {    *( (short *) samples) = *tmp1;    samples += 2;    tmp1 += 2;  }  *pnt += 64;  return ret;}int synth_1to1(real *bandPtr,int channel,unsigned char *out,int *pnt){  static const int step = 2;  int bo;  short *samples = (short *) (out + *pnt);  real *b0,(*buf)[0x110];  int clip = 0;  int bo1;  bo = gmp->synth_bo;  if(!channel) {    bo--;    bo &= 0xf;    buf = gmp->synth_buffs[0];  }  else {    samples++;    buf = gmp->synth_buffs[1];  }  if(bo & 0x1) {    b0 = buf[0];    bo1 = bo;    dct64(buf[1]+((bo+1)&0xf),buf[0]+bo,bandPtr);  }  else {    b0 = buf[1];    bo1 = bo+1;    dct64(buf[0]+bo,buf[1]+bo+1,bandPtr);  }  gmp->synth_bo = bo;  {    register int j;    real *window = decwin + 16 - bo1;    for (j=16;j;j--,b0+=0x10,window+=0x20,samples+=step)    {      real sum;      sum  = window[0x0] * b0[0x0];      sum -= window[0x1] * b0[0x1];      sum += window[0x2] * b0[0x2];      sum -= window[0x3] * b0[0x3];      sum += window[0x4] * b0[0x4];      sum -= window[0x5] * b0[0x5];      sum += window[0x6] * b0[0x6];      sum -= window[0x7] * b0[0x7];      sum += window[0x8] * b0[0x8];      sum -= window[0x9] * b0[0x9];      sum += window[0xA] * b0[0xA];      sum -= window[0xB] * b0[0xB];      sum += window[0xC] * b0[0xC];      sum -= window[0xD] * b0[0xD];      sum += window[0xE] * b0[0xE];      sum -= window[0xF] * b0[0xF];      WRITE_SAMPLE(samples,sum,clip);    }    {      real sum;      sum  = window[0x0] * b0[0x0];      sum += window[0x2] * b0[0x2];      sum += window[0x4] * b0[0x4];      sum += window[0x6] * b0[0x6];      sum += window[0x8] * b0[0x8];      sum += window[0xA] * b0[0xA];      sum += window[0xC] * b0[0xC];      sum += window[0xE] * b0[0xE];      WRITE_SAMPLE(samples,sum,clip);      b0-=0x10,window-=0x20,samples+=step;    }    window += bo1<<1;    for (j=15;j;j--,b0-=0x10,window-=0x20,samples+=step)    {      real sum;      sum = -window[-0x1] * b0[0x0];      sum -= window[-0x2] * b0[0x1];      sum -= window[-0x3] * b0[0x2];      sum -= window[-0x4] * b0[0x3];      sum -= window[-0x5] * b0[0x4];      sum -= window[-0x6] * b0[0x5];      sum -= window[-0x7] * b0[0x6];      sum -= window[-0x8] * b0[0x7];      sum -= window[-0x9] * b0[0x8];      sum -= window[-0xA] * b0[0x9];      sum -= window[-0xB] * b0[0xA];      sum -= window[-0xC] * b0[0xB];      sum -= window[-0xD] * b0[0xC];      sum -= window[-0xE] * b0[0xD];      sum -= window[-0xF] * b0[0xE];      sum -= window[-0x0] * b0[0xF];      WRITE_SAMPLE(samples,sum,clip);    }  }  *pnt += 128;  return clip;}#endif