ref: b276dee4f0888ff5eaff9f03244e2d49f6e7241b
parent: 53a75769de213bbe237879c6b3bab8a2e6f4bc5c
author: Paul Brossier <piem@piem.org>
date: Sat Sep 8 11:59:11 EDT 2007
mfcc.{c,h}, filterbank.{c,h}: move filter initialisation into new_aubio_filterbank_mfcc
--- a/src/filterbank.c
+++ b/src/filterbank.c
@@ -23,13 +23,17 @@
*/
#include "aubio_priv.h"
+#include "sample.h"
#include "filterbank.h"
+#define USE_EQUAL_GAIN 1
+#define VERY_SMALL_NUMBER 2e-42
+
/** \brief A structure to store a set of n_filters filters of lenghts win_s */
struct aubio_filterbank_t_ {uint_t win_s;
uint_t n_filters;
- fvec_t *filters;
+ fvec_t **filters;
};
aubio_filterbank_t * new_aubio_filterbank(uint_t n_filters, uint_t win_s){@@ -40,21 +44,141 @@
fb->n_filters=n_filters;
/** allocating filter tables */
- fb->filters=AUBIO_ARRAY(n_filters,fvec_t);
+ fb->filters=AUBIO_ARRAY(fvec_t*,n_filters);
for (filter_cnt=0; filter_cnt<n_filters; filter_cnt++)
/* considering one-channel filters */
- filters[filter_cnt]=new_fvec(win_s, 1);
+ fb->filters[filter_cnt]=new_fvec(win_s, 1);
+ return fb;
}
+aubio_filterbank_t * new_aubio_filterbank_mfcc(uint_t n_filters, uint_t win_s, smpl_t samplerate, smpl_t freq_min, smpl_t freq_max){+ smpl_t nyquist = samplerate/2.;
+ uint_t style = 1;
+ aubio_filterbank_t * fb = new_aubio_filterbank(n_filters, win_s);
+
+ uint_t n, i, k, *fft_peak, M, next_peak;
+ smpl_t norm, mel_freq_max, mel_freq_min, norm_fact, height, inc, val,
+ freq_bw_mel, *mel_peak, *height_norm, *lin_peak;
+
+ mel_peak = height_norm = lin_peak = NULL;
+ fft_peak = NULL;
+ norm = 1;
+
+ mel_freq_max = 1127 * log(1 + freq_max / 700);
+ mel_freq_min = 1127 * log(1 + freq_min / 700);
+ freq_bw_mel = (mel_freq_max - mel_freq_min) / fb->n_filters;
+
+ mel_peak = (smpl_t *)malloc((fb->n_filters + 2) * sizeof(smpl_t));
+ /* +2 for zeros at start and end */
+ lin_peak = (smpl_t *)malloc((fb->n_filters + 2) * sizeof(smpl_t));
+ fft_peak = (uint_t *)malloc((fb->n_filters + 2) * sizeof(uint_t));
+ height_norm = (smpl_t *)malloc(fb->n_filters * sizeof(smpl_t));
+
+ if(mel_peak == NULL || height_norm == NULL ||
+ lin_peak == NULL || fft_peak == NULL)
+ return NULL;
+
+ M = fb->win_s >> 1;
+
+ mel_peak[0] = mel_freq_min;
+ lin_peak[0] = 700 * (exp(mel_peak[0] / 1127) - 1);
+ fft_peak[0] = lin_peak[0] / nyquist * M;
+
+
+ for (n = 1; n <= fb->n_filters; n++){ + /*roll out peak locations - mel, linear and linear on fft window scale */
+ mel_peak[n] = mel_peak[n - 1] + freq_bw_mel;
+ lin_peak[n] = 700 * (exp(mel_peak[n] / 1127) -1);
+ fft_peak[n] = lin_peak[n] / nyquist * M;
+ }
+
+ for (n = 0; n < fb->n_filters; n++){+ /*roll out normalised gain of each peak*/
+ if (style == USE_EQUAL_GAIN){+ height = 1;
+ norm_fact = norm;
+ }
+ else{+ height = 2 / (lin_peak[n + 2] - lin_peak[n]);
+ norm_fact = norm / (2 / (lin_peak[2] - lin_peak[0]));
+ }
+ height_norm[n] = height * norm_fact;
+ }
+
+ i = 0;
+
+ for(n = 0; n < fb->n_filters; n++){+
+ /*calculate the rise increment*/
+ if(n > 0)
+ inc = height_norm[n] / (fft_peak[n] - fft_peak[n - 1]);
+ else
+ inc = height_norm[n] / fft_peak[n];
+ val = 0;
+
+ /*zero the start of the array*/
+ for(k = 0; k < i; k++)
+ //fft_tables[n][k] = 0.f;
+ fb->filters[n]->data[0][k]=0.f;
+
+ /*fill in the rise */
+ for(; i <= fft_peak[n]; i++){ + // fft_tables[n][i] = val;
+ fb->filters[n]->data[0][k]=val;
+ val += inc;
+ }
+
+ /*calculate the fall increment */
+ inc = height_norm[n] / (fft_peak[n + 1] - fft_peak[n]);
+
+ val = 0;
+ next_peak = fft_peak[n + 1];
+
+ /*reverse fill the 'fall' */
+ for(i = next_peak; i > fft_peak[n]; i--){ + //fft_tables[n][i] = val;
+ fb->filters[n]->data[0][k]=val;
+ val += inc;
+ }
+
+ /*zero the rest of the array*/
+ for(k = next_peak + 1; k < fb->win_s; k++)
+ //fft_tables[n][k] = 0.f;
+ fb->filters[n]->data[0][k]=0.f;
+ }
+
+ free(mel_peak);
+ free(lin_peak);
+ free(height_norm);
+ free(fft_peak);
+
+ return fb;
+
+}
+
+
void del_aubio_filterbank(aubio_filterbank_t * fb){-
- int filter_cnt;
+ uint_t filter_cnt;
/** deleting filter tables first */
for (filter_cnt=0; filter_cnt<fb->n_filters; filter_cnt++)
del_fvec(fb->filters[filter_cnt]);
AUBIO_FREE(fb->filters);
AUBIO_FREE(fb);
-
}
+void aubio_filterbank_do(aubio_filterbank_t * f, cvec_t * in, fvec_t *out) {+ uint_t n, filter_cnt;
+ for(filter_cnt = 0; filter_cnt < f->n_filters; filter_cnt++){+ out->data[0][filter_cnt] = 0.f;
+ for(n = 0; n < f->win_s; n++){+ out->data[0][filter_cnt] += in->norm[0][n]
+ * f->filters[filter_cnt]->data[0][n];
+ }
+ out->data[0][filter_cnt] =
+ LOG(out->data[0][filter_cnt] < VERY_SMALL_NUMBER ?
+ VERY_SMALL_NUMBER : out->data[0][filter_cnt]);
+ }
+
+ return;
+}
--- a/src/filterbank.h
+++ b/src/filterbank.h
@@ -43,16 +43,8 @@
aubio_filterbank_t * new_aubio_filterbank(uint_t n_filters, uint_t win_s);
-/** destroy filterbank object
-
- \param fb filterbank, as returned by new_aubio_filterbank method
-
-*/
-void del_aubio_filterbank(aubio_filterbank_t * fb);
-
/** filterbank initialization for mel filters
- \param fb filterbank, as returned by new_aubio_filterbank method
\param nyquist nyquist frequency, i.e. half of the sampling rate
\param style libxtract style
\param freqmin lowest filter frequency
@@ -59,15 +51,20 @@
\param freqmax highest filter frequency
*/
-void aubio_filterbank_mfcc_init(aubio_filterbank_t * fb, smpl_t nyquist, int style, smpl_t freq_min, smpl_t freq_max);
+aubio_filterbank_t * new_aubio_filterbank_mfcc(uint_t n_filters, uint_t win_s, smpl_t samplerate, smpl_t freq_min, smpl_t freq_max);
-// Initialization
-/** \brief A function to initialise a mel filter bank
- *
- * It is up to the caller to pass in a pointer to memory allocated for freq_bands arrays of length N. This function populates these arrays with magnitude coefficients representing the mel filterbank on a linear scale
- */
-int aubio_mfcc_init(int N, smpl_t nyquist, int style, smpl_t freq_min, smpl_t freq_max, int freq_bands, smpl_t ** fft_tables);
+/** destroy filterbank object
+
+ \param fb filterbank, as returned by new_aubio_filterbank method
+
+*/
+void del_aubio_filterbank(aubio_filterbank_t * fb);
+
+/** compute filterbank
+
+*/
+void aubio_filterbank_do(aubio_filterbank_t * fb, cvec_t * in, fvec_t *out);
#ifdef __cplusplus
}
--- a/src/mfcc.c
+++ b/src/mfcc.c
@@ -27,10 +27,6 @@
#include "mfcc.h"
#include "math.h"
-#define VERY_SMALL_NUMBER 2e-42
-#define USE_EQUAL_GAIN 1
-
-
/** Internal structure for mfcc object **/
struct aubio_mfcc_t_{@@ -47,17 +43,6 @@
};
-/** filterbank initialization for mel filters
-
- \param fb filterbank, as returned by new_aubio_filterbank method
- \param nyquist nyquist frequency, i.e. half of the sampling rate
- \param style libxtract style
- \param freqmin lowest filter frequency
- \param freqmax highest filter frequency
-
-*/
-void aubio_filterbank_mfcc_init(aubio_filterbank_t * fb, smpl_t nyquist, int style, smpl_t freq_min, smpl_t freq_max);
-
aubio_mfcc_t * new_aubio_mfcc (uint_t win_s, uint_t samplerate ,uint_t n_coefs, smpl_t lowfreq, smpl_t highfreq, uint_t channels){/** allocating space for mfcc object */
aubio_mfcc_t * mfcc = AUBIO_NEW(aubio_mfcc_t);
@@ -73,10 +58,10 @@
mfcc->highfreq=highfreq;
/** filterbank allocation */
- mfcc->fb = new_aubio_filterbank(n_filters, mfcc->win_s);
+ mfcc->fb = new_aubio_filterbank_mfcc(n_filters, mfcc->win_s, samplerate, lowfreq, highfreq);
/** allocating space for fft object (used for dct) */
- mfcc->fft_dct=new_aubio_mfft(mfcc->win_s, 1);
+ mfcc->fft_dct=new_aubio_mfft(n_filters, 1);
/** allocating buffers */
mfcc->in_dct=new_fvec(mfcc->win_s, 1);
@@ -83,9 +68,6 @@
mfcc->fftgrain_dct=new_cvec(n_filters, 1);
- /** populating the filterbank */
- aubio_filterbank_mfcc_init(mfcc->fb, (mfcc->samplerate)/2, mfcc->lowfreq, mfcc->highfreq);
-
return mfcc;
};
@@ -103,18 +85,8 @@
}
void aubio_mfcc_do(aubio_mfcc_t * mf, cvec_t *in, fvec_t *out){-
- aubio_filterbank_t *f = mf->fb;
- uint_t n, filter_cnt;
-
- for(filter_cnt = 0; filter_cnt < f->n_filters; filter_cnt++){- mf->in_dct->data[0][filter_cnt] = 0.f;
- for(n = 0; n < mf->win_s; n++){- mf->in_dct->data[0][filter_cnt] += in->norm[0][n] * f->filters[filter_cnt]->data[0][n];
- }
- mf->in_dct->data[0][filter_cnt] = LOG(mf->in_dct->data[0][filter_cnt] < VERY_SMALL_NUMBER ? VERY_SMALL_NUMBER : mf->in_dct->data[0][filter_cnt]);
- }
-
+ // compute filterbank
+ aubio_filterbank_do(mf->fb, in, mf->in_dct);
//TODO: check that zero padding
// the following line seems useless since the in_dct buffer has the correct size
//for(n = filter + 1; n < N; n++) result[n] = 0;
@@ -125,115 +97,15 @@
}
void aubio_dct_do(aubio_mfcc_t * mf, fvec_t *in, fvec_t *out){+ uint_t i;
//compute mag spectrum
aubio_mfft_do (mf->fft_dct, in, mf->fftgrain_dct);
-
- int i;
//extract real part of fft grain
- for(i=0; i<mf->n_coefs ;i++){- out->data[0][i]= mf->fftgrain_dct->norm[0][i]*COS(mf->fftgrain_dct->phas[0][i]);
+ //for(i=0; i<mf->n_coefs ;i++){+ for(i=0; i<out->length;i++){+ out->data[0][i]= mf->fftgrain_dct->norm[0][i]
+ *COS(mf->fftgrain_dct->phas[0][i]);
}
-
return;
-}
-
-void aubio_filterbank_mfcc_init(aubio_filterbank_t * fb, smpl_t nyquist, int style, smpl_t freq_min, smpl_t freq_max){-
- int n, i, k, *fft_peak, M, next_peak;
- smpl_t norm, mel_freq_max, mel_freq_min, norm_fact, height, inc, val,
- freq_bw_mel, *mel_peak, *height_norm, *lin_peak;
-
- mel_peak = height_norm = lin_peak = NULL;
- fft_peak = NULL;
- norm = 1;
-
- mel_freq_max = 1127 * log(1 + freq_max / 700);
- mel_freq_min = 1127 * log(1 + freq_min / 700);
- freq_bw_mel = (mel_freq_max - mel_freq_min) / fb->n_filters;
-
- mel_peak = (smpl_t *)malloc((fb->n_filters + 2) * sizeof(smpl_t));
- /* +2 for zeros at start and end */
- lin_peak = (smpl_t *)malloc((fb->n_filters + 2) * sizeof(smpl_t));
- fft_peak = (int *)malloc((fb->n_filters + 2) * sizeof(int));
- height_norm = (smpl_t *)malloc(fb->n_filters * sizeof(smpl_t));
-
- if(mel_peak == NULL || height_norm == NULL ||
- lin_peak == NULL || fft_peak == NULL)
- return NULL;
-
- M = fb->win_s >> 1;
-
- mel_peak[0] = mel_freq_min;
- lin_peak[0] = 700 * (exp(mel_peak[0] / 1127) - 1);
- fft_peak[0] = lin_peak[0] / nyquist * M;
-
-
- for (n = 1; n <= fb->n_filters; n++){ - /*roll out peak locations - mel, linear and linear on fft window scale */
- mel_peak[n] = mel_peak[n - 1] + freq_bw_mel;
- lin_peak[n] = 700 * (exp(mel_peak[n] / 1127) -1);
- fft_peak[n] = lin_peak[n] / nyquist * M;
- }
-
- for (n = 0; n < fb->n_filters; n++){- /*roll out normalised gain of each peak*/
- if (style == USE_EQUAL_GAIN){- height = 1;
- norm_fact = norm;
- }
- else{- height = 2 / (lin_peak[n + 2] - lin_peak[n]);
- norm_fact = norm / (2 / (lin_peak[2] - lin_peak[0]));
- }
- height_norm[n] = height * norm_fact;
- }
-
- i = 0;
-
- for(n = 0; n < fb->n_filters; n++){-
- /*calculate the rise increment*/
- if(n > 0)
- inc = height_norm[n] / (fft_peak[n] - fft_peak[n - 1]);
- else
- inc = height_norm[n] / fft_peak[n];
- val = 0;
-
- /*zero the start of the array*/
- for(k = 0; k < i; k++)
- //fft_tables[n][k] = 0.f;
- fb->filters[n]->data[0][k]=0.f;
-
- /*fill in the rise */
- for(; i <= fft_peak[n]; i++){ - // fft_tables[n][i] = val;
- fb->filters[n]->data[0][k]=val;
- val += inc;
- }
-
- /*calculate the fall increment */
- inc = height_norm[n] / (fft_peak[n + 1] - fft_peak[n]);
-
- val = 0;
- next_peak = fft_peak[n + 1];
-
- /*reverse fill the 'fall' */
- for(i = next_peak; i > fft_peak[n]; i--){ - //fft_tables[n][i] = val;
- fb->filters[n]->data[0][k]=val;
- val += inc;
- }
-
- /*zero the rest of the array*/
- for(k = next_peak + 1; k < fb->win_s; k++)
- //fft_tables[n][k] = 0.f;
- fb->filters[n]->data[0][k]=0.f;
- }
-
- free(mel_peak);
- free(lin_peak);
- free(height_norm);
- free(fft_peak);
-
}
--- a/src/mfcc.h
+++ b/src/mfcc.h
@@ -29,6 +29,7 @@
extern "C" {#endif
+#include "sample.h"
#include "filterbank.h"
typedef struct aubio_mfcc_t_ aubio_mfcc_t;