denoise.c

/* Copyright (c) 2017 Mozilla */
/*
   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions
   are met:

   - Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.

   - Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "kiss_fft.h"
#include "common.h"
#include <math.h>
#include "rnnoise.h"
#include "pitch.h"
#include "arch.h"
#include "celt_lpc.h"
#include <assert.h>

#define PREEMPHASIS (0.85f)

#define FRAME_SIZE_SHIFT 2
#define FRAME_SIZE (40<<FRAME_SIZE_SHIFT)
#define WINDOW_SIZE (2*FRAME_SIZE)
#define FREQ_SIZE (FRAME_SIZE + 1)

#define PITCH_MIN_PERIOD 32
#define PITCH_MAX_PERIOD 256
#define PITCH_FRAME_SIZE 320
#define PITCH_BUF_SIZE (PITCH_MAX_PERIOD+PITCH_FRAME_SIZE)

#define SQUARE(x) ((x)*(x))

#define SMOOTH_BANDS 1

#if SMOOTH_BANDS
#define NB_BANDS 18
#else
#define NB_BANDS 17
#endif

#define CEPS_MEM 8
#define NB_DELTA_CEPS 6

#define NB_FEATURES (2*NB_BANDS+3+LPC_ORDER)


#ifndef TRAINING
#define TRAINING 0
#endif

static const opus_int16 eband5ms[] = {
/*0  200 400 600 800  1k 1.2 1.4 1.6  2k 2.4 2.8 3.2  4k 4.8 5.6 6.8  8k*/
  0,  1,  2,  3,  4,  5,  6,  7,  8, 10, 12, 14, 16, 20, 24, 28, 34, 40
};


typedef struct {
  int init;
  kiss_fft_state *kfft;
  float half_window[FRAME_SIZE];
  float dct_table[NB_BANDS*NB_BANDS];
} CommonState;

struct DenoiseState {
  float analysis_mem[FRAME_SIZE];
  float cepstral_mem[CEPS_MEM][NB_BANDS];
  int memid;
  float synthesis_mem[FRAME_SIZE];
  float pitch_buf[PITCH_BUF_SIZE];
  float pitch_enh_buf[PITCH_BUF_SIZE];
  float last_gain;
  int last_period;
  float mem_hp_x[2];
  float lastg[NB_BANDS];
};

#if SMOOTH_BANDS
void compute_band_energy(float *bandE, const kiss_fft_cpx *X) {
  int i;
  float sum[NB_BANDS] = {0};
  for (i=0;i<NB_BANDS-1;i++)
  {
    int j;
    int band_size;
    band_size = (eband5ms[i+1]-eband5ms[i])<<FRAME_SIZE_SHIFT;
    for (j=0;j<band_size;j++) {
      float tmp;
      float frac = (float)j/band_size;
      tmp = SQUARE(X[(eband5ms[i]<<FRAME_SIZE_SHIFT) + j].r);
      tmp += SQUARE(X[(eband5ms[i]<<FRAME_SIZE_SHIFT) + j].i);
      sum[i] += (1-frac)*tmp;
      sum[i+1] += frac*tmp;
    }
  }
  sum[0] *= 2;
  sum[NB_BANDS-1] *= 2;
  for (i=0;i<NB_BANDS;i++)
  {
    bandE[i] = sum[i];
  }
}

void compute_band_corr(float *bandE, const kiss_fft_cpx *X, const kiss_fft_cpx *P) {
  int i;
  float sum[NB_BANDS] = {0};
  for (i=0;i<NB_BANDS-1;i++)
  {
    int j;
    int band_size;
    band_size = (eband5ms[i+1]-eband5ms[i])<<FRAME_SIZE_SHIFT;
    for (j=0;j<band_size;j++) {
      float tmp;
      float frac = (float)j/band_size;
      tmp = X[(eband5ms[i]<<FRAME_SIZE_SHIFT) + j].r * P[(eband5ms[i]<<FRAME_SIZE_SHIFT) + j].r;
      tmp += X[(eband5ms[i]<<FRAME_SIZE_SHIFT) + j].i * P[(eband5ms[i]<<FRAME_SIZE_SHIFT) + j].i;
      sum[i] += (1-frac)*tmp;
      sum[i+1] += frac*tmp;
    }
  }
  sum[0] *= 2;
  sum[NB_BANDS-1] *= 2;
  for (i=0;i<NB_BANDS;i++)
  {
    bandE[i] = sum[i];
  }
}

void interp_band_gain(float *g, const float *bandE) {
  int i;
  memset(g, 0, FREQ_SIZE);
  for (i=0;i<NB_BANDS-1;i++)
  {
    int j;
    int band_size;
    band_size = (eband5ms[i+1]-eband5ms[i])<<FRAME_SIZE_SHIFT;
    for (j=0;j<band_size;j++) {
      float frac = (float)j/band_size;
      g[(eband5ms[i]<<FRAME_SIZE_SHIFT) + j] = (1-frac)*bandE[i] + frac*bandE[i+1];
    }
  }
}
#else
void compute_band_energy(float *bandE, const kiss_fft_cpx *X) {
  int i;
  for (i=0;i<NB_BANDS;i++)
  {
    int j;
    opus_val32 sum = 0;
    for (j=0;j<(eband5ms[i+1]-eband5ms[i])<<FRAME_SIZE_SHIFT;j++) {
      sum += SQUARE(X[(eband5ms[i]<<FRAME_SIZE_SHIFT) + j].r);
      sum += SQUARE(X[(eband5ms[i]<<FRAME_SIZE_SHIFT) + j].i);
    }
    bandE[i] = sum;
  }
}

void interp_band_gain(float *g, const float *bandE) {
  int i;
  memset(g, 0, FREQ_SIZE);
  for (i=0;i<NB_BANDS;i++)
  {
    int j;
    for (j=0;j<(eband5ms[i+1]-eband5ms[i])<<FRAME_SIZE_SHIFT;j++)
      g[(eband5ms[i]<<FRAME_SIZE_SHIFT) + j] = bandE[i];
  }
}
#endif


CommonState common;

static void check_init() {
  int i;
  if (common.init) return;
  common.kfft = opus_fft_alloc_twiddles(2*FRAME_SIZE, NULL, NULL, NULL, 0);
  for (i=0;i<FRAME_SIZE;i++)
    common.half_window[i] = sin(.5*M_PI*sin(.5*M_PI*(i+.5)/FRAME_SIZE) * sin(.5*M_PI*(i+.5)/FRAME_SIZE));
  for (i=0;i<NB_BANDS;i++) {
    int j;
    for (j=0;j<NB_BANDS;j++) {
      common.dct_table[i*NB_BANDS + j] = cos((i+.5)*j*M_PI/NB_BANDS);
      if (j==0) common.dct_table[i*NB_BANDS + j] *= sqrt(.5);
    }
  }
  common.init = 1;
}

static void dct(float *out, const float *in) {
  int i;
  check_init();
  for (i=0;i<NB_BANDS;i++) {
    int j;
    float sum = 0;
    for (j=0;j<NB_BANDS;j++) {
      sum += in[j] * common.dct_table[j*NB_BANDS + i];
    }
    out[i] = sum*sqrt(2./22);
  }
}

#if 0
static void idct(float *out, const float *in) {
  int i;
  check_init();
  for (i=0;i<NB_BANDS;i++) {
    int j;
    float sum = 0;
    for (j=0;j<NB_BANDS;j++) {
      sum += in[j] * common.dct_table[i*NB_BANDS + j];
    }
    out[i] = sum*sqrt(2./22);
  }
}
#endif

static void forward_transform(kiss_fft_cpx *out, const float *in) {
  int i;
  kiss_fft_cpx x[WINDOW_SIZE];
  kiss_fft_cpx y[WINDOW_SIZE];
  check_init();
  for (i=0;i<WINDOW_SIZE;i++) {
    x[i].r = in[i];
    x[i].i = 0;
  }
  opus_fft(common.kfft, x, y, 0);
  for (i=0;i<FREQ_SIZE;i++) {
    out[i] = y[i];
  }
}

static void inverse_transform(float *out, const kiss_fft_cpx *in) {
  int i;
  kiss_fft_cpx x[WINDOW_SIZE];
  kiss_fft_cpx y[WINDOW_SIZE];
  check_init();
  for (i=0;i<FREQ_SIZE;i++) {
    x[i] = in[i];
  }
  for (;i<WINDOW_SIZE;i++) {
    x[i].r = x[WINDOW_SIZE - i].r;
    x[i].i = -x[WINDOW_SIZE - i].i;
  }
  opus_fft(common.kfft, x, y, 0);
  /* output in reverse order for IFFT. */
  out[0] = WINDOW_SIZE*y[0].r;
  for (i=1;i<WINDOW_SIZE;i++) {
    out[i] = WINDOW_SIZE*y[WINDOW_SIZE - i].r;
  }
}

static void apply_window(float *x) {
  int i;
  check_init();
  for (i=0;i<FRAME_SIZE;i++) {
    x[i] *= common.half_window[i];
    x[WINDOW_SIZE - 1 - i] *= common.half_window[i];
  }
}

int rnnoise_get_size() {
  return sizeof(DenoiseState);
}

int rnnoise_init(DenoiseState *st) {
  memset(st, 0, sizeof(*st));
  return 0;
}

DenoiseState *rnnoise_create() {
  DenoiseState *st;
  st = malloc(rnnoise_get_size());
  rnnoise_init(st);
  return st;
}

void rnnoise_destroy(DenoiseState *st) {
  free(st);
}

#if TRAINING
int lowpass = FREQ_SIZE;
int band_lp = NB_BANDS;
#endif

short float2short(float x)
{
  int i;
  i = (int)floor(.5+x);
  return IMAX(-32767, IMIN(32767, i));
}

static float frame_analysis(DenoiseState *st, signed char *iexc, short *pred, short *pcm, float *lpc, kiss_fft_cpx *X, float *Ex, const float *in) {
  int i;
  float x[WINDOW_SIZE];
  float x0[WINDOW_SIZE];
  float ac[LPC_ORDER+1];
  float rc[LPC_ORDER];
  float g;
  RNN_COPY(x, st->analysis_mem, FRAME_SIZE);
  for (i=0;i<FRAME_SIZE;i++) x[FRAME_SIZE + i] = in[i];
  RNN_COPY(st->analysis_mem, in, FRAME_SIZE);
  RNN_COPY(x0, x, WINDOW_SIZE);
  apply_window(x);
  forward_transform(X, x);
#if TRAINING
  for (i=lowpass;i<FREQ_SIZE;i++)
    X[i].r = X[i].i = 0;
#endif
  compute_band_energy(Ex, X);
  {
    float e;
    float g_1;
    if (0) {
      _celt_autocorr(x, ac, NULL, 0, LPC_ORDER, WINDOW_SIZE);
    } else {
      float Xr[FREQ_SIZE];
      kiss_fft_cpx X_auto[FREQ_SIZE];
      float x_auto[FRAME_SIZE];
      interp_band_gain(Xr, Ex);
      RNN_CLEAR(X_auto, FREQ_SIZE);
      for (i=0;i<160;i++) X_auto[i].r = Xr[i];
      inverse_transform(x_auto, X_auto);
      for (i=0;i<LPC_ORDER+1;i++) ac[i] = x_auto[i];
    }
    /* -40 dB noise floor. */
    ac[0] += ac[0]*1e-4 + 320/12/38.;
    /* Lag windowing. */
    for (i=1;i<LPC_ORDER+1;i++) ac[i] *= (1 - 6e-5*i*i);
    e = _celt_lpc(lpc, rc, ac, LPC_ORDER);
    g = sqrt((1e-10+e)*(1./FRAME_SIZE));
    g_1 = 1./g;
#if 0
    for(i=0;i<WINDOW_SIZE;i++) printf("%f ", x[i]);
    printf("\n");
#endif
#if 0
    printf("1 ");
    for(i=0;i<LPC_ORDER;i++) printf("%f ", lpc[i]);
    printf("\n");
#endif
    for (i=0;i<FRAME_SIZE;i++) {
      int j;
      float *z;
      float tmp;
      int nexc;
      z = &x0[i]+FRAME_SIZE/2;
      tmp = z[0];
      for (j=0;j<LPC_ORDER;j++) tmp += lpc[j]*z[-1-j];
      pcm[i] = float2short(z[0]);
      pred[i] = float2short(z[0] - tmp);
      nexc = (int)floor(.5 + 16*g_1*tmp);
      nexc = IMAX(-128, IMIN(127, nexc));
      iexc[i] = nexc;
#if 0
      printf("%f\n", g_1*tmp);
#endif
    }
  }
  return g;
}

static int compute_frame_features(DenoiseState *st, signed char *iexc, short *pred, short *pcm, kiss_fft_cpx *X, kiss_fft_cpx *P,
                                  float *Ex, float *Ep, float *Exp, float *features, const float *in) {
  int i;
  float E = 0;
  float Ly[NB_BANDS];
  float lpc[LPC_ORDER];
  float p[WINDOW_SIZE];
  float pitch_buf[PITCH_BUF_SIZE];
  int pitch_index;
  float gain;
  float tmp[NB_BANDS];
  float follow, logMax;
  float g;
  g = frame_analysis(st, iexc, pred, pcm, lpc, X, Ex, in);
  RNN_MOVE(st->pitch_buf, &st->pitch_buf[FRAME_SIZE], PITCH_BUF_SIZE-FRAME_SIZE);
  RNN_COPY(&st->pitch_buf[PITCH_BUF_SIZE-FRAME_SIZE], in, FRAME_SIZE);
  //pre[0] = &st->pitch_buf[0];
  RNN_COPY(pitch_buf, &st->pitch_buf[0], PITCH_BUF_SIZE);
  pitch_downsample(pitch_buf, PITCH_BUF_SIZE);
  pitch_search(pitch_buf+PITCH_MAX_PERIOD, pitch_buf, PITCH_FRAME_SIZE<<1,
               (PITCH_MAX_PERIOD-3*PITCH_MIN_PERIOD)<<1, &pitch_index);
  //printf("%d ", pitch_index);
  pitch_index = 2*PITCH_MAX_PERIOD-pitch_index;
  //printf("%d ", pitch_index);
  gain = remove_doubling(pitch_buf, 2*PITCH_MAX_PERIOD, 2*PITCH_MIN_PERIOD,
          2*PITCH_FRAME_SIZE, &pitch_index, st->last_period, st->last_gain);
  st->last_period = pitch_index;
  st->last_gain = gain;
  //printf("%d %f\n", pitch_index, gain);
  for (i=0;i<WINDOW_SIZE;i++)
    p[i] = st->pitch_buf[PITCH_BUF_SIZE-WINDOW_SIZE-pitch_index/2+i];
  apply_window(p);
  forward_transform(P, p);
  compute_band_energy(Ep, P);
  compute_band_corr(Exp, X, P);
  for (i=0;i<NB_BANDS;i++) Exp[i] = Exp[i]/sqrt(.001+Ex[i]*Ep[i]);
#if 0
  for (i=0;i<NB_BANDS;i++) printf("%f ", Exp[i]);
  printf("\n");
#endif
  dct(tmp, Exp);
  for (i=0;i<NB_BANDS;i++) features[NB_BANDS+i] = tmp[i];
  features[NB_BANDS] -= 1.3;
  features[NB_BANDS+1] -= 0.9;
  logMax = -2;
  follow = -2;
  for (i=0;i<NB_BANDS;i++) {
    Ly[i] = log10(1e-2+Ex[i]);
    Ly[i] = MAX16(logMax-8, MAX16(follow-2.5, Ly[i]));
    logMax = MAX16(logMax, Ly[i]);
    follow = MAX16(follow-2.5, Ly[i]);
    E += Ex[i];
  }
  dct(features, Ly);
  features[0] -= 4;
#if 0
  for (i=0;i<NB_BANDS;i++) printf("%f ", Ly[i]);
  printf("\n");
#endif
  features[2*NB_BANDS] = .01*(pitch_index-200);
  features[2*NB_BANDS+1] = gain;
  features[2*NB_BANDS+2] = log10(g);
  for (i=0;i<LPC_ORDER;i++) features[2*NB_BANDS+3+i] = lpc[i];
#if 0
  for (i=0;i<NB_FEATURES;i++) printf("%f ", features[i]);
  printf("\n");
#endif
  return TRAINING && E < 0.1;
}

static void frame_synthesis(DenoiseState *st, float *out, const kiss_fft_cpx *y) {
  float x[WINDOW_SIZE];
  int i;
  inverse_transform(x, y);
  apply_window(x);
  for (i=0;i<FRAME_SIZE;i++) out[i] = x[i] + st->synthesis_mem[i];
  RNN_COPY(st->synthesis_mem, &x[FRAME_SIZE], FRAME_SIZE);
}

static void biquad(float *y, float mem[2], const float *x, const float *b, const float *a, int N) {
  int i;
  for (i=0;i<N;i++) {
    float xi, yi;
    xi = x[i];
    yi = x[i] + mem[0];
    mem[0] = mem[1] + (b[0]*(double)xi - a[0]*(double)yi);
    mem[1] = (b[1]*(double)xi - a[1]*(double)yi);
    y[i] = yi;
  }
}

static void preemphasis(float *y, float *mem, const float *x, float coef, int N) {
  int i;
  for (i=0;i<N;i++) {
    float yi;
    yi = x[i] + *mem;
    *mem = -coef*x[i];
    y[i] = yi;
  }
}

void pitch_filter(kiss_fft_cpx *X, const kiss_fft_cpx *P, const float *Ex, const float *Ep,
                  const float *Exp, const float *g) {
  int i;
  float r[NB_BANDS];
  float rf[FREQ_SIZE] = {0};
  for (i=0;i<NB_BANDS;i++) {
#if 0
    if (Exp[i]>g[i]) r[i] = 1;
    else r[i] = Exp[i]*(1-g[i])/(.001 + g[i]*(1-Exp[i]));
    r[i] = MIN16(1, MAX16(0, r[i]));
#else
    if (Exp[i]>g[i]) r[i] = 1;
    else r[i] = SQUARE(Exp[i])*(1-SQUARE(g[i]))/(.001 + SQUARE(g[i])*(1-SQUARE(Exp[i])));
    r[i] = sqrt(MIN16(1, MAX16(0, r[i])));
#endif
    r[i] *= sqrt(Ex[i]/(1e-8+Ep[i]));
  }
  interp_band_gain(rf, r);
  for (i=0;i<FREQ_SIZE;i++) {
    X[i].r += rf[i]*P[i].r;
    X[i].i += rf[i]*P[i].i;
  }
  float newE[NB_BANDS];
  compute_band_energy(newE, X);
  float norm[NB_BANDS];
  float normf[FREQ_SIZE]={0};
  for (i=0;i<NB_BANDS;i++) {
    norm[i] = sqrt(Ex[i]/(1e-8+newE[i]));
  }
  interp_band_gain(normf, norm);
  for (i=0;i<FREQ_SIZE;i++) {
    X[i].r *= normf[i];
    X[i].i *= normf[i];
  }
}

float rnnoise_process_frame(DenoiseState *st, float *out, const float *in) {
  int i;
  kiss_fft_cpx X[FREQ_SIZE];
  kiss_fft_cpx P[WINDOW_SIZE];
  float x[FRAME_SIZE];
  float Ex[NB_BANDS], Ep[NB_BANDS];
  float Exp[NB_BANDS];
  float features[NB_FEATURES];
  float g[NB_BANDS];
  float gf[FREQ_SIZE]={1};
  float vad_prob = 0;
  int silence=0;
  static const float a_hp[2] = {-1.99599, 0.99600};
  static const float b_hp[2] = {-2, 1};
  biquad(x, st->mem_hp_x, in, b_hp, a_hp, FRAME_SIZE);
  //silence = compute_frame_features(st, NULL, X, P, Ex, Ep, Exp, features, x);

  if (!silence) {
    pitch_filter(X, P, Ex, Ep, Exp, g);
    for (i=0;i<NB_BANDS;i++) {
      float alpha = .6f;
      g[i] = MAX16(g[i], alpha*st->lastg[i]);
      st->lastg[i] = g[i];
    }
    interp_band_gain(gf, g);
#if 1
    for (i=0;i<FREQ_SIZE;i++) {
      X[i].r *= gf[i];
      X[i].i *= gf[i];
    }
#endif
  }

  frame_synthesis(st, out, X);
  return vad_prob;
}

#if TRAINING

/*static float uni_rand() {
  return rand()/(double)RAND_MAX-.5;
}

static void rand_resp(float *a, float *b) {
  a[0] = .75*uni_rand();
  a[1] = .75*uni_rand();
  b[0] = .75*uni_rand();
  b[1] = .75*uni_rand();
}*/

int main(int argc, char **argv) {
  int i;
  int count=0;
  static const float a_hp[2] = {-1.99599, 0.99600};
  static const float b_hp[2] = {-2, 1};
  float mem_hp_x[2]={0};
  float mem_preemph=0;
  float x[FRAME_SIZE];
  FILE *f1;
  FILE *fexc;
  FILE *ffeat;
  FILE *fpred;
  FILE *fpcm;
  signed char iexc[FRAME_SIZE];
  short pred[FRAME_SIZE];
  short pcm[FRAME_SIZE];
  DenoiseState *st;
  st = rnnoise_create();
  if (argc!=6) {
    fprintf(stderr, "usage: %s <speech> <exc out> <features out> <prediction out> <pcm out> \n", argv[0]);
    return 1;
  }
  f1 = fopen(argv[1], "r");
  fexc = fopen(argv[2], "w");
  ffeat = fopen(argv[3], "w");
  fpred = fopen(argv[4], "w");
  fpcm = fopen(argv[5], "w");
  while (1) {
    kiss_fft_cpx X[FREQ_SIZE], P[WINDOW_SIZE];
    float Ex[NB_BANDS], Ep[NB_BANDS];
    float Exp[NB_BANDS];
    float Ln[NB_BANDS];
    float features[NB_FEATURES];
    float g[NB_BANDS];
    short tmp[FRAME_SIZE];
    float E=0;
    fread(tmp, sizeof(short), FRAME_SIZE, f1);
    if (feof(f1)) {
      return 0;
    }
    for (i=0;i<FRAME_SIZE;i++) x[i] = tmp[i];
    for (i=0;i<FRAME_SIZE;i++) x[i] += rand()/(float)RAND_MAX - .5;
    for (i=0;i<FRAME_SIZE;i++) E += tmp[i]*(float)tmp[i];
    biquad(x, mem_hp_x, x, b_hp, a_hp, FRAME_SIZE);
    preemphasis(x, &mem_preemph, x, PREEMPHASIS, FRAME_SIZE);

    compute_frame_features(st, iexc, pred, pcm, X, P, Ex, Ep, Exp, features, x);
#if 1
    fwrite(iexc, sizeof(signed char), FRAME_SIZE, fexc);
    fwrite(features, sizeof(float), NB_FEATURES, ffeat);
    fwrite(pred, sizeof(short), FRAME_SIZE, fpred);
    fwrite(pcm, sizeof(short), FRAME_SIZE, fpcm);
#endif
    count++;
  }
  //fprintf(stderr, "matrix size: %d x %d\n", count, NB_FEATURES + 2*NB_BANDS + 1);
  fclose(f1);
  fclose(fexc);
  return 0;
}

#endif