source: src/mfcc.h @ 21bd43c

/*
   Copyright (C) 2006 Amaury Hazan
   Ported to aubio from LibXtract
   http://libxtract.sourceforge.net/
   

   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 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.

   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.

*/

#ifndef MFCC_H 
#define MFCC_H 

#ifdef __cplusplus
extern "C" {
#endif

#include "filterbank.h"

//libXtract constants and enums
// TODO: remove them 

#define XTRACT_SQ(a) ((a) * (a))
#define XTRACT_MIN(a, b) ((a) < (b) ? (a) : (b))
#define XTRACT_MAX(a, b) ((a) > (b) ? (a) : (b))
#define XTRACT_NEEDS_FFTW printf("LibXtract must be compiled with fftw support to use this function.\n")
#define XTRACT_VERY_SMALL_NUMBER 2e-42
#define XTRACT_LOG_LIMIT XTRACT_VERY_SMALL_NUMBER
#define XTRACT_LOG_LIMIT_DB -96.0
#define XTRACT_DB_SCALE_OFFSET 96.0
#define XTRACT_VERY_BIG_NUMBER 2e42
#define XTRACT_SR_UPPER_LIMIT 192000.0
#define XTRACT_SR_LOWER_LIMIT 22050.0
#define XTRACT_SR_DEFAULT 44100.0
#define XTRACT_FUNDAMENTAL_DEFAULT 440.0
#define XTRACT_CHECK_nyquist if(!nyquist) nyquist = XTRACT_SR_DEFAULT / 2
#define XTRACT_CHECK_q if(!q) q = XTRACT_SR_DEFAULT / N
#define XTRACT_IS_ODD(x) (x % 2 != 0 ? 1 : 0) 
#define XTRACT_SR_LIMIT SR_UPPER_LIMIT
#define XTRACT_FFT_BANDS_MIN 16
#define XTRACT_FFT_BANDS_MAX 65536
#define XTRACT_FFT_BANDS_DEF 1024
#define XTRACT_SPEC_BW_MIN 0.168 /* Minimum spectral bandwidth \
            (= SR_LOWER_LIMIT / FFT_BANDS_MAX*/ 
#define XTRACT_SPEC_BW_MAX 12000.0 /* SR_UPPER_LIMIT / FFT_BANDS_MIN */
#define XTRACT_SPEC_BW_DEF 43.066 /* SR_DEFAULT / FFT_BANDS_DEF */

/** \brief Enumeration of feature initialisation functions */
enum xtract_feature_init_ {
    XTRACT_INIT_MFCC = 100,
    XTRACT_INIT_BARK
};

/** \brief Enumeration of feature types */
enum xtract_feature_types_ {
    XTRACT_SCALAR,
    XTRACT_VECTOR,
    XTRACT_DELTA
};

/** \brief Enumeration of mfcc types */
enum xtract_mfcc_types_ {
    XTRACT_EQUAL_GAIN,
    XTRACT_EQUAL_AREA
};

/** \brief Enumeration of return codes */
enum xtract_return_codes_ {
    XTRACT_SUCCESS,
    XTRACT_MALLOC_FAILED,
    XTRACT_BAD_ARGV,
    XTRACT_BAD_VECTOR_SIZE,
    XTRACT_NO_RESULT,
    XTRACT_FEATURE_NOT_IMPLEMENTED
};

/** \brief Enumeration of spectrum types */
enum xtract_spectrum_ {
    XTRACT_MAGNITUDE_SPECTRUM,
    XTRACT_LOG_MAGNITUDE_SPECTRUM,
    XTRACT_POWER_SPECTRUM,
    XTRACT_LOG_POWER_SPECTRUM
};

/** \brief Enumeration of data types*/
typedef enum type_ {
    XTRACT_FLOAT,
    XTRACT_FLOATARRAY,
    XTRACT_INT,
    XTRACT_MEL_FILTER
} xtract_type_t;

/** \brief Enumeration of units*/
typedef enum unit_ {
    /* NONE, ANY */
    XTRACT_HERTZ = 2,
    XTRACT_ANY_AMPLITUDE_HERTZ,
    XTRACT_DBFS,
    XTRACT_DBFS_HERTZ,
    XTRACT_PERCENT,
    XTRACT_SONE
} xtract_unit_t;

/** \brief Boolean */
typedef enum {
    XTRACT_FALSE,
    XTRACT_TRUE
} xtract_bool_t;

/** \brief Enumeration of vector format types*/
typedef enum xtract_vector_ {
    /* N/2 magnitude/log-magnitude/power/log-power coeffs and N/2 frequencies */
    XTRACT_SPECTRAL,     
    /* N spectral amplitudes */
    XTRACT_SPECTRAL_MAGNITUDES, 
    /* N/2 magnitude/log-magnitude/power/log-power peak coeffs and N/2 
     * frequencies */
    XTRACT_SPECTRAL_PEAKS,
    /* N spectral peak amplitudes */
    XTRACT_SPECTRAL_PEAKS_MAGNITUDES,
    /* N spectral peak frequencies */
    XTRACT_SPECTRAL_PEAKS_FREQUENCIES,
    /* N/2 magnitude/log-magnitude/power/log-power harmonic peak coeffs and N/2 
     * frequencies */
    XTRACT_SPECTRAL_HARMONICS,
    /* N spectral harmonic amplitudes */
    XTRACT_SPECTRAL_HARMONICS_MAGNITUDES,
    /* N spectral harmonic frequencies */
    XTRACT_SPECTRAL_HARMONICS_FREQUENCIES,
    XTRACT_ARBITRARY_SERIES,
    XTRACT_AUDIO_SAMPLES,
    XTRACT_MEL_COEFFS, 
    XTRACT_BARK_COEFFS,
    XTRACT_NO_DATA
} xtract_vector_t;


typedef struct aubio_mfcc_t_ aubio_mfcc_t;

// Creation

/** create mfcc object

  \param win_s size of analysis buffer (and length the FFT transform)
  \param samplerate 
  \param n_coefs: number of desired coefs
  \param lowfreq: lowest frequency to use in filterbank
  \param highfreq highest frequency to use in filterbank
  \param channels number of channels

*/
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);

// Deletion

/** delete mfcc object

  \param mf mfcc object as returned by new_aubio_mfcc

*/
void del_aubio_mfcc(aubio_mfcc_t *mf);

// Process

/** mfcc object processing

  \param mf mfcc object as returned by new_aubio_mfcc
  \param in input spectrum (win_s long)
  \param out output mel coefficients buffer (n_filters/2 +1 long)

*/

void aubio_mfcc_do(aubio_mfcc_t * mf, cvec_t *in, fvec_t *out);

/** intermediate dct involved in aubio_mfcc_do

  \param mf mfcc object as returned by new_aubio_mfcc
  \param in input spectrum (n_filters long)
  \param out output mel coefficients buffer (n_filters/2 +1 long)

*/

void aubio_dct_do(aubio_mfcc_t * mf, fvec_t *in, fvec_t *out);




//old code


/*
int aubio_mfcc_do(const float *data, const int N, const void *argv, float *result, aubio_mfft_t *fft_dct, cvec_t *fftgrain_dct);

int aubio_dct_do(const float *data, const int N, const void *argv, float *result, aubio_mfft_t *fft_dct, cvec_t *fftgrain_dct);*/




#ifdef __cplusplus
}
#endif

#endif