X-Git-Url: http://git.tremily.us/?a=blobdiff_plain;f=src%2Fmathutils.c;h=7d2424e05e2ff12b1625b1400e54ae9c653b0185;hb=HEAD;hp=f82549a6dda9dbfec2e90fd7cb1338cb74c9f854;hpb=ade9afe663f3175a6ed9e75c0866fa436591e3e1;p=aubio.git

diff --git a/src/mathutils.c b/src/mathutils.c
index f82549a6..7d2424e0 100644
--- a/src/mathutils.c
+++ b/src/mathutils.c
@@ -1,31 +1,86 @@
 /*
-   Copyright (C) 2003 Paul Brossier
+  Copyright (C) 2003-2013 Paul Brossier <piem@aubio.org>
 
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2 of the License, or
-   (at your option) any later version.
+  This file is part of aubio.
 
-   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 General Public License for more details.
+  aubio is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
 
-   You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+  aubio 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 General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with aubio.  If not, see <http://www.gnu.org/licenses/>.
 
 */
 
 /* see in mathutils.h for doc */
 
 #include "aubio_priv.h"
-#include "sample.h"
+#include "fvec.h"
 #include "mathutils.h"
+#include "musicutils.h"
 #include "config.h"
 
-void aubio_window(smpl_t *w, uint_t size, aubio_window_type wintype) {
-  uint_t i;
+
+/** Window types */
+typedef enum
+{
+  aubio_win_rectangle,
+  aubio_win_hamming,
+  aubio_win_hanning,
+  aubio_win_hanningz,
+  aubio_win_blackman,
+  aubio_win_blackman_harris,
+  aubio_win_gaussian,
+  aubio_win_welch,
+  aubio_win_parzen,
+  aubio_win_default = aubio_win_hanningz,
+} aubio_window_type;
+
+fvec_t *
+new_aubio_window (char_t * window_type, uint_t length)
+{
+  fvec_t * win = new_fvec (length);
+  fvec_set_window (win, window_type);
+  return win;
+}
+
+uint_t fvec_set_window (fvec_t *win, char_t *window_type) {
+  smpl_t * w = win->data;
+  uint_t i, size = win->length;
+  aubio_window_type wintype;
+  if (window_type == NULL) {
+      AUBIO_ERR ("window type can not be null.\n");
+      return 1;
+  } else if (strcmp (window_type, "rectangle") == 0)
+      wintype = aubio_win_rectangle;
+  else if (strcmp (window_type, "hamming") == 0)
+      wintype = aubio_win_hamming;
+  else if (strcmp (window_type, "hanning") == 0)
+      wintype = aubio_win_hanning;
+  else if (strcmp (window_type, "hanningz") == 0)
+      wintype = aubio_win_hanningz;
+  else if (strcmp (window_type, "blackman") == 0)
+      wintype = aubio_win_blackman;
+  else if (strcmp (window_type, "blackman_harris") == 0)
+      wintype = aubio_win_blackman_harris;
+  else if (strcmp (window_type, "gaussian") == 0)
+      wintype = aubio_win_gaussian;
+  else if (strcmp (window_type, "welch") == 0)
+      wintype = aubio_win_welch;
+  else if (strcmp (window_type, "parzen") == 0)
+      wintype = aubio_win_parzen;
+  else if (strcmp (window_type, "default") == 0)
+      wintype = aubio_win_default;
+  else {
+      AUBIO_ERR ("unknown window type `%s`.\n", window_type);
+      return 1;
+  }
   switch(wintype) {
     case aubio_win_rectangle:
       for (i=0;i<size;i++)
@@ -57,186 +112,213 @@ void aubio_window(smpl_t *w, uint_t size, aubio_window_type wintype) {
           - 0.01168 * COS(3.0*TWO_PI*i/(size-1.0));
       break;
     case aubio_win_gaussian:
-      for (i=0;i<size;i++)
-        w[i] = EXP(- 1.0 / SQR(size) * SQR(2.0*i-size));
+      {
+        lsmp_t a, b, c = 0.5;
+        uint_t n;
+        for (n = 0; n < size; n++)
+        {
+          a = (n-c*(size-1))/(SQR(c)*(size-1));
+          b = -c*SQR(a);
+          w[n] = EXP(b);
+        }
+      }
       break;
     case aubio_win_welch:
       for (i=0;i<size;i++)
-        w[i] = 1.0 - SQR((2*i-size)/(size+1.0));
+        w[i] = 1.0 - SQR((2.*i-size)/(size+1.0));
       break;
     case aubio_win_parzen:
       for (i=0;i<size;i++)
-        w[i] = 1.0 - ABS((2*i-size)/(size+1.0));
+        w[i] = 1.0 - ABS((2.*i-size)/(size+1.0));
       break;
     default:
       break;
   }
+  return 0;
 }
 
-smpl_t aubio_unwrap2pi(smpl_t phase) {
+smpl_t
+aubio_unwrap2pi (smpl_t phase)
+{
   /* mod(phase+pi,-2pi)+pi */
-  return phase + TWO_PI * (1. + FLOOR(-(phase+PI)/TWO_PI));
+  return phase + TWO_PI * (1. + FLOOR (-(phase + PI) / TWO_PI));
 }
 
-smpl_t vec_mean(fvec_t *s) {
-  uint_t i,j;
-  smpl_t tmp = 0.0f;
-  for (i=0; i < s->channels; i++)
-    for (j=0; j < s->length; j++)
-      tmp += s->data[i][j];
-  return tmp/(smpl_t)(s->length);
+smpl_t
+fvec_mean (fvec_t * s)
+{
+  uint_t j;
+  smpl_t tmp = 0.0;
+  for (j = 0; j < s->length; j++) {
+    tmp += s->data[j];
+  }
+  return tmp / (smpl_t) (s->length);
 }
 
-smpl_t vec_sum(fvec_t *s) {
-  uint_t i,j;
-  smpl_t tmp = 0.0f;
-  for (i=0; i < s->channels; i++)
-    for (j=0; j < s->length; j++)
-      tmp += s->data[i][j];
+smpl_t
+fvec_sum (fvec_t * s)
+{
+  uint_t j;
+  smpl_t tmp = 0.0;
+  for (j = 0; j < s->length; j++) {
+    tmp += s->data[j];
+  }
   return tmp;
 }
 
-smpl_t vec_max(fvec_t *s) {
-  uint_t i,j;
-  smpl_t tmp = 0.0f;
-  for (i=0; i < s->channels; i++)
-    for (j=0; j < s->length; j++)
-      tmp = (tmp > s->data[i][j])? tmp : s->data[i][j];
+smpl_t
+fvec_max (fvec_t * s)
+{
+  uint_t j;
+  smpl_t tmp = 0.0;
+  for (j = 0; j < s->length; j++) {
+    tmp = (tmp > s->data[j]) ? tmp : s->data[j];
+  }
   return tmp;
 }
 
-smpl_t vec_min(fvec_t *s) {
-  uint_t i,j;
-  smpl_t tmp = s->data[0][0];
-  for (i=0; i < s->channels; i++)
-    for (j=0; j < s->length; j++)
-      tmp = (tmp < s->data[i][j])? tmp : s->data[i][j]  ;
+smpl_t
+fvec_min (fvec_t * s)
+{
+  uint_t j;
+  smpl_t tmp = s->data[0];
+  for (j = 0; j < s->length; j++) {
+    tmp = (tmp < s->data[j]) ? tmp : s->data[j];
+  }
   return tmp;
 }
 
-uint_t vec_min_elem(fvec_t *s) {
-  uint_t i,j=0, pos=0.;
-  smpl_t tmp = s->data[0][0];
-  for (i=0; i < s->channels; i++)
-    for (j=0; j < s->length; j++) {
-      pos = (tmp < s->data[i][j])? pos : j;
-      tmp = (tmp < s->data[i][j])? tmp : s->data[i][j]  ;
-    }
+uint_t
+fvec_min_elem (fvec_t * s)
+{
+  uint_t j, pos = 0.;
+  smpl_t tmp = s->data[0];
+  for (j = 0; j < s->length; j++) {
+    pos = (tmp < s->data[j]) ? pos : j;
+    tmp = (tmp < s->data[j]) ? tmp : s->data[j];
+  }
   return pos;
 }
 
-uint_t vec_max_elem(fvec_t *s) {
-  uint_t i,j=0, pos=0.;
-  smpl_t tmp = 0.0f;
-  for (i=0; i < s->channels; i++)
-    for (j=0; j < s->length; j++) {
-      pos = (tmp > s->data[i][j])? pos : j;
-      tmp = (tmp > s->data[i][j])? tmp : s->data[i][j]  ;
-    }
+uint_t
+fvec_max_elem (fvec_t * s)
+{
+  uint_t j, pos = 0;
+  smpl_t tmp = 0.0;
+  for (j = 0; j < s->length; j++) {
+    pos = (tmp > s->data[j]) ? pos : j;
+    tmp = (tmp > s->data[j]) ? tmp : s->data[j];
+  }
   return pos;
 }
 
-void vec_shift(fvec_t *s) {
-  uint_t i,j;
-  //smpl_t tmp = 0.0f;
-  for (i=0; i < s->channels; i++)
-    for (j=0; j < s->length / 2 ; j++) {
-      //tmp = s->data[i][j];
-      //s->data[i][j] = s->data[i][j+s->length/2];
-      //s->data[i][j+s->length/2] = tmp;
-      ELEM_SWAP(s->data[i][j],s->data[i][j+s->length/2]);
-    }
+void
+fvec_shift (fvec_t * s)
+{
+  uint_t j;
+  for (j = 0; j < s->length / 2; j++) {
+    ELEM_SWAP (s->data[j], s->data[j + s->length / 2]);
+  }
+}
+
+smpl_t
+fvec_local_energy (fvec_t * f)
+{
+  smpl_t energy = 0.;
+  uint_t j;
+  for (j = 0; j < f->length; j++) {
+    energy += SQR (f->data[j]);
+  }
+  return energy / f->length;
 }
 
-smpl_t vec_local_energy(fvec_t * f) {
-  smpl_t locE = 0.;
-  uint_t i,j;
-  for (i=0;i<f->channels;i++)
-    for (j=0;j<f->length;j++)
-      locE+=SQR(f->data[i][j]);
-  return locE;
+smpl_t
+fvec_local_hfc (fvec_t * v)
+{
+  smpl_t hfc = 0.;
+  uint_t j;
+  for (j = 0; j < v->length; j++) {
+    hfc += (j + 1) * v->data[j];
+  }
+  return hfc;
 }
 
-smpl_t vec_local_hfc(fvec_t * f) {
-  smpl_t locE = 0.;
-  uint_t i,j;
-  for (i=0;i<f->channels;i++)
-    for (j=0;j<f->length;j++)
-      locE+=(i+1)*f->data[i][j];
-  return locE;
+void
+fvec_min_removal (fvec_t * v)
+{
+  smpl_t v_min = fvec_min (v);
+  fvec_add (v,  - v_min );
 }
 
-smpl_t vec_alpha_norm(fvec_t * DF, smpl_t alpha) {
+smpl_t
+fvec_alpha_norm (fvec_t * o, smpl_t alpha)
+{
+  uint_t j;
   smpl_t tmp = 0.;
-  uint_t i,j;
-  for (i=0;i<DF->channels;i++)
-    for (j=0;j<DF->length;j++)
-      tmp += POW(ABS(DF->data[i][j]),alpha);
-  return POW(tmp/DF->length,1./alpha);
-}
-
-void vec_dc_removal(fvec_t * mag) {
-    smpl_t mini = 0.;
-    uint_t length = mag->length, i=0, j;
-    mini = vec_min(mag);
-    for (j=0;j<length;j++) {
-      mag->data[i][j] -= mini;
-    }
+  for (j = 0; j < o->length; j++) {
+    tmp += POW (ABS (o->data[j]), alpha);
+  }
+  return POW (tmp / o->length, 1. / alpha);
 }
 
-void vec_alpha_normalise(fvec_t * mag, uint_t alpha) {
-  smpl_t alphan = 1.;
-  uint_t length = mag->length, i=0, j;
-  alphan = vec_alpha_norm(mag,alpha);
-  for (j=0;j<length;j++){
-    mag->data[i][j] /= alphan;
+void
+fvec_alpha_normalise (fvec_t * o, smpl_t alpha)
+{
+  uint_t j;
+  smpl_t norm = fvec_alpha_norm (o, alpha);
+  for (j = 0; j < o->length; j++) {
+    o->data[j] /= norm;
   }
 }
 
-void vec_add(fvec_t * mag, smpl_t threshold) {
-  uint_t length = mag->length, i=0, j;
-  for (j=0;j<length;j++) {
-    mag->data[i][j] += threshold;
+void
+fvec_add (fvec_t * o, smpl_t val)
+{
+  uint_t j;
+  for (j = 0; j < o->length; j++) {
+    o->data[j] += val;
   }
 }
 
-void vec_adapt_thres(fvec_t * vec, fvec_t * tmp,
+void fvec_adapt_thres(fvec_t * vec, fvec_t * tmp,
     uint_t post, uint_t pre) {
-  uint_t length = vec->length, i=0, j;
+  uint_t length = vec->length, j;
   for (j=0;j<length;j++) {
-    vec->data[i][j] -= vec_moving_thres(vec, tmp, post, pre, j);
+    vec->data[j] -= fvec_moving_thres(vec, tmp, post, pre, j);
   }
 }
 
-smpl_t vec_moving_thres(fvec_t * vec, fvec_t * tmpvec,
-    uint_t post, uint_t pre, uint_t pos) {
-  smpl_t * medar = (smpl_t *)tmpvec->data[0];
+smpl_t
+fvec_moving_thres (fvec_t * vec, fvec_t * tmpvec,
+    uint_t post, uint_t pre, uint_t pos)
+{
   uint_t k;
-  uint_t win_length =  post+pre+1;
-  uint_t length =  vec->length;
+  smpl_t *medar = (smpl_t *) tmpvec->data;
+  uint_t win_length = post + pre + 1;
+  uint_t length = vec->length;
   /* post part of the buffer does not exist */
-  if (pos<post+1) {
-    for (k=0;k<post+1-pos;k++)
-      medar[k] = 0.; /* 0-padding at the beginning */
-    for (k=post+1-pos;k<win_length;k++)
-      medar[k] = vec->data[0][k+pos-post];
-  /* the buffer is fully defined */
-  } else if (pos+pre<length) {
-    for (k=0;k<win_length;k++)
-      medar[k] = vec->data[0][k+pos-post];
-  /* pre part of the buffer does not exist */
+  if (pos < post + 1) {
+    for (k = 0; k < post + 1 - pos; k++)
+      medar[k] = 0.;            /* 0-padding at the beginning */
+    for (k = post + 1 - pos; k < win_length; k++)
+      medar[k] = vec->data[k + pos - post];
+    /* the buffer is fully defined */
+  } else if (pos + pre < length) {
+    for (k = 0; k < win_length; k++)
+      medar[k] = vec->data[k + pos - post];
+    /* pre part of the buffer does not exist */
   } else {
-    for (k=0;k<length-pos+post+1;k++)
-      medar[k] = vec->data[0][k+pos-post];
-    for (k=length-pos+post+1;k<win_length;k++)
-      medar[k] = 0.; /* 0-padding at the end */
+    for (k = 0; k < length - pos + post; k++)
+      medar[k] = vec->data[k + pos - post];
+    for (k = length - pos + post; k < win_length; k++)
+      medar[k] = 0.;            /* 0-padding at the end */
   }
-  return vec_median(tmpvec);
+  return fvec_median (tmpvec);
 }
 
-smpl_t vec_median(fvec_t * input) {
+smpl_t fvec_median (fvec_t * input) {
   uint_t n = input->length;
-  smpl_t * arr = (smpl_t *) input->data[0];
+  smpl_t * arr = (smpl_t *) input->data;
   uint_t low, high ;
   uint_t median;
   uint_t middle, ll, hh;
@@ -285,186 +367,185 @@ smpl_t vec_median(fvec_t * input) {
   }
 }
 
-smpl_t vec_quadint(fvec_t * x,uint_t pos) {
-  uint_t span = 2;
-  smpl_t step = 1./200.;
-  /* hack : init resold to - something (in case x[pos+-span]<0)) */
-  smpl_t res, frac, s0, s1, s2, exactpos = (smpl_t)pos, resold = -1000.;
-  if ((pos > span) && (pos < x->length-span)) {
-    s0 = x->data[0][pos-span];
-    s1 = x->data[0][pos]     ;
-    s2 = x->data[0][pos+span];
-    /* increase frac */
-    for (frac = 0.; frac < 2.; frac = frac + step) {
-      res = aubio_quadfrac(s0, s1, s2, frac);
-      if (res > resold)
-        resold = res;
-      else {
-        exactpos += (frac-step)*2. - 1.;
-        break;
-      }
-    }
-  }
-  return exactpos;
-}
-
-smpl_t vec_quadint_min(fvec_t * x,uint_t pos, uint_t span) {
-  smpl_t step = 1./200.;
-  /* init resold to - something (in case x[pos+-span]<0)) */
-  smpl_t res, frac, s0, s1, s2, exactpos = (smpl_t)pos, resold = 100000.;
-  if ((pos > span) && (pos < x->length-span)) {
-    s0 = x->data[0][pos-span];
-    s1 = x->data[0][pos]     ;
-    s2 = x->data[0][pos+span];
-    /* increase frac */
-    for (frac = 0.; frac < 2.; frac = frac + step) {
-      res = aubio_quadfrac(s0, s1, s2, frac);
-      if (res < resold) {
-        resold = res;
-      } else {
-        exactpos += (frac-step)*span - span/2.;
-        break;
-      }
-    }
-  }
-  return exactpos;
-}
-
-smpl_t aubio_quadfrac(smpl_t s0, smpl_t s1, smpl_t s2, smpl_t pf) {
-  smpl_t tmp = s0 + (pf/2.) * (pf * ( s0 - 2.*s1 + s2 ) - 3.*s0 + 4.*s1 - s2);
+smpl_t fvec_quadint (fvec_t * x, uint_t pos) {
+  smpl_t s0, s1, s2;
+  uint_t x0 = (pos < 1) ? pos : pos - 1;
+  uint_t x2 = (pos + 1 < x->length) ? pos + 1 : pos;
+  if (x0 == pos) return (x->data[pos] <= x->data[x2]) ? pos : x2;
+  if (x2 == pos) return (x->data[pos] <= x->data[x0]) ? pos : x0;
+  s0 = x->data[x0];
+  s1 = x->data[pos];
+  s2 = x->data[x2];
+  return pos + 0.5 * (s2 - s0 ) / (s2 - 2.* s1 + s0);
+}
+
+smpl_t fvec_quadratic_peak_pos (fvec_t * x, uint_t pos) {
+  smpl_t s0, s1, s2;
+  uint_t x0 = (pos < 1) ? pos : pos - 1;
+  uint_t x2 = (pos + 1 < x->length) ? pos + 1 : pos;
+  if (x0 == pos) return (x->data[pos] <= x->data[x2]) ? pos : x2;
+  if (x2 == pos) return (x->data[pos] <= x->data[x0]) ? pos : x0;
+  s0 = x->data[x0];
+  s1 = x->data[pos];
+  s2 = x->data[x2];
+  return pos + 0.5 * (s0 - s2 ) / (s0 - 2.* s1 + s2);
+}
+
+uint_t fvec_peakpick(fvec_t * onset, uint_t pos) {
+  uint_t tmp=0;
+  tmp = (onset->data[pos] > onset->data[pos-1]
+      &&  onset->data[pos] > onset->data[pos+1]
+      &&  onset->data[pos] > 0.);
   return tmp;
 }
 
-uint_t vec_peakpick(fvec_t * onset, uint_t pos) {
-  uint_t i=0, tmp=0;
-  /*for (i=0;i<onset->channels;i++)*/
-  tmp = (onset->data[i][pos] > onset->data[i][pos-1]
-      &&  onset->data[i][pos] > onset->data[i][pos+1]
-      &&  onset->data[i][pos] > 0.);
+smpl_t
+aubio_quadfrac (smpl_t s0, smpl_t s1, smpl_t s2, smpl_t pf)
+{
+  smpl_t tmp =
+      s0 + (pf / 2.) * (pf * (s0 - 2. * s1 + s2) - 3. * s0 + 4. * s1 - s2);
   return tmp;
 }
 
-smpl_t aubio_freqtomidi(smpl_t freq) {
+smpl_t
+aubio_freqtomidi (smpl_t freq)
+{
+  if (freq < 2. || freq > 100000.) return 0.; // avoid nans and infs
   /* log(freq/A-2)/log(2) */
-  smpl_t midi = freq/6.875;
-  midi = LOG(midi)/0.69314718055995;
+  smpl_t midi = freq / 6.875;
+  midi = LOG (midi) / 0.69314718055995;
   midi *= 12;
   midi -= 3;
   return midi;
 }
 
-smpl_t aubio_miditofreq(smpl_t midi) {
-  smpl_t freq = (midi+3.)/12.;
-  freq = EXP(freq*0.69314718055995);
+smpl_t
+aubio_miditofreq (smpl_t midi)
+{
+  if (midi > 140.) return 0.; // avoid infs
+  smpl_t freq = (midi + 3.) / 12.;
+  freq = EXP (freq * 0.69314718055995);
   freq *= 6.875;
   return freq;
 }
 
-smpl_t aubio_bintofreq(smpl_t bin, smpl_t samplerate, smpl_t fftsize) {
-  smpl_t freq = samplerate/fftsize;
-  return freq*bin;
+smpl_t
+aubio_bintofreq (smpl_t bin, smpl_t samplerate, smpl_t fftsize)
+{
+  smpl_t freq = samplerate / fftsize;
+  return freq * MAX(bin, 0);
 }
 
-smpl_t aubio_bintomidi(smpl_t bin, smpl_t samplerate, smpl_t fftsize) {
-  smpl_t midi = aubio_bintofreq(bin,samplerate,fftsize);
-  return aubio_freqtomidi(midi);
+smpl_t
+aubio_bintomidi (smpl_t bin, smpl_t samplerate, smpl_t fftsize)
+{
+  smpl_t midi = aubio_bintofreq (bin, samplerate, fftsize);
+  return aubio_freqtomidi (midi);
 }
 
-smpl_t aubio_freqtobin(smpl_t freq, smpl_t samplerate, smpl_t fftsize) {
-  smpl_t bin = fftsize/samplerate;
-  return freq*bin;
+smpl_t
+aubio_freqtobin (smpl_t freq, smpl_t samplerate, smpl_t fftsize)
+{
+  smpl_t bin = fftsize / samplerate;
+  return MAX(freq, 0) * bin;
 }
 
-smpl_t aubio_miditobin(smpl_t midi, smpl_t samplerate, smpl_t fftsize) {
-  smpl_t freq = aubio_miditofreq(midi);
-  return aubio_freqtobin(freq,samplerate,fftsize);
+smpl_t
+aubio_miditobin (smpl_t midi, smpl_t samplerate, smpl_t fftsize)
+{
+  smpl_t freq = aubio_miditofreq (midi);
+  return aubio_freqtobin (freq, samplerate, fftsize);
 }
 
-/** returns 1 if wassilence is 0 and RMS(ibuf)<threshold
- * \bug mono
- */
-uint_t aubio_silence_detection(fvec_t * ibuf, smpl_t threshold) {
-  smpl_t loudness = 0;
-  uint_t i=0,j;
-  for (j=0;j<ibuf->length;j++) {
-    loudness += SQR(ibuf->data[i][j]);
+uint_t
+aubio_is_power_of_two (uint_t a)
+{
+  if ((a & (a - 1)) == 0) {
+    return 1;
+  } else {
+    return 0;
   }
-  loudness = SQRT(loudness);
-  loudness /= (smpl_t)ibuf->length;
-  loudness = LIN2DB(loudness);
+}
 
-  return (loudness < threshold);
+uint_t
+aubio_next_power_of_two (uint_t a)
+{
+  uint_t i = 1;
+  while (i < a) i <<= 1;
+  return i;
 }
 
-/** returns level log(RMS(ibuf)) if < threshold, 1 otherwise
- * \bug mono
- */
-smpl_t aubio_level_detection(fvec_t * ibuf, smpl_t threshold) {
-  smpl_t loudness = 0;
-  uint_t i=0,j;
-  for (j=0;j<ibuf->length;j++) {
-    loudness += SQR(ibuf->data[i][j]);
-  }
-  loudness = SQRT(loudness);
-  loudness /= (smpl_t)ibuf->length;
-  loudness = LIN2DB(loudness);
+smpl_t
+aubio_db_spl (fvec_t * o)
+{
+  return 10. * LOG10 (fvec_local_energy (o));
+}
 
-  if (loudness < threshold)
+uint_t
+aubio_silence_detection (fvec_t * o, smpl_t threshold)
+{
+  return (aubio_db_spl (o) < threshold);
+}
+
+smpl_t
+aubio_level_detection (fvec_t * o, smpl_t threshold)
+{
+  smpl_t db_spl = aubio_db_spl (o);
+  if (db_spl < threshold) {
     return 1.;
-  else
-    return loudness;
+  } else {
+    return db_spl;
+  }
 }
 
-smpl_t aubio_zero_crossing_rate(fvec_t * input) {
-  uint_t i=0,j;
+smpl_t
+aubio_zero_crossing_rate (fvec_t * input)
+{
+  uint_t j;
   uint_t zcr = 0;
-  for ( j = 1; j < input->length; j++ ) {
-    // previous was negative
-    if( input->data[i][j-1] <= 0. ) {
-      if ( input->data[i][j] > 0. ) {
+  for (j = 1; j < input->length; j++) {
+    // previous was strictly negative
+    if (input->data[j - 1] < 0.) {
+      // current is positive or null
+      if (input->data[j] >= 0.) {
+        zcr += 1;
+      }
+      // previous was positive or null
+    } else {
+      // current is strictly negative
+      if (input->data[j] < 0.) {
         zcr += 1;
       }
-    //previous was positive
-    } else if ( input->data[i][j] <= 0. ) {
-      zcr += 1;
     }
   }
-  return zcr/(smpl_t)input->length;
-}
-
-smpl_t aubio_spectral_centroid(cvec_t * spectrum, smpl_t samplerate) {
-  uint_t i=0, j;
-  smpl_t sum = 0., sc = 0.;
-  for ( j = 0; j < spectrum->length; j++ ) {
-    sum += spectrum->norm[i][j];
-  }
-  if (sum == 0.) return 0.;
-  for ( j = 0; j < spectrum->length; j++ ) {
-    sc += (smpl_t)j * spectrum->norm[i][j];
-  }
-  return sc / sum * samplerate / (smpl_t)(spectrum->length);
-}
-
-void aubio_autocorr(fvec_t * input, fvec_t * output) {
-  uint_t i = 0, j = 0, length = input->length;
-  smpl_t * data = input->data[0];
-  smpl_t * acf = output->data[0];
-  smpl_t tmp =0.;
-  for(i=0;i<length;i++){
-    for(j=i;j<length;j++){
-      tmp += data[j-i]*data[j];
+  return zcr / (smpl_t) input->length;
+}
+
+void
+aubio_autocorr (fvec_t * input, fvec_t * output)
+{
+  uint_t i, j, length = input->length;
+  smpl_t *data, *acf;
+  smpl_t tmp = 0;
+  data = input->data;
+  acf = output->data;
+  for (i = 0; i < length; i++) {
+    tmp = 0.;
+    for (j = i; j < length; j++) {
+      tmp += data[j - i] * data[j];
     }
-    acf[i] = tmp /(smpl_t)(length-i);
-    tmp = 0.0;
+    acf[i] = tmp / (smpl_t) (length - i);
   }
 }
 
-void aubio_cleanup(void) {
-#if FFTW3_SUPPORT
-  fftw_cleanup();
+void
+aubio_cleanup (void)
+{
+#ifdef HAVE_FFTW3F
+  fftwf_cleanup ();
 #else
-#if FFTW3F_SUPPORT
-  fftwf_cleanup();
+#ifdef HAVE_FFTW3
+  fftw_cleanup ();
 #endif
 #endif
 }