annotate src/descriptors.c @ 104:a32738e9d955

- Fixes to descriptors.c where no break statement was given for certain cases is switch conditionals
- Added LPC and LPCC extraction functions. LPC implements Durbin method as described in Rabiner and Juang and implemented in Dr. Dobbs 1994 edition by Jutta Degener

/* libxtract feature extraction library
 *  
 * Copyright (C) 2006 Jamie Bullock
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
 * USA.
 */

#include "xtract/libxtract.h"
#include "xtract_macros_private.h"
#include <stdlib.h>
#include <string.h>
#define XTRACT

void *xtract_make_descriptors(){

    int f , F;
    char *name, *p_name, *desc, *p_desc, *author; 
    float *argv_min, *argv_max, *argv_def, *result_min, *result_max;
    int *argc, *year, *argv_donor;
    xtract_vector_t *data_format, *result_format; 
    xtract_unit_t *data_unit, *argv_unit, *result_unit;
    xtract_bool_t *is_scalar;
    xtract_function_descriptor_t *fd, *d;
    xtract_type_t *argv_type;

    f = F = XTRACT_FEATURES;

    fd = malloc(XTRACT_FEATURES * sizeof(xtract_function_descriptor_t));

    /* FIX - this file probably needs a rewrite for readability */

    while(f--){

	d = &fd[f];
	argc = &d->argc;
	argv_type = &d->argv.type;

	switch(f){

	    case XTRACT_VARIANCE:
	    case XTRACT_STANDARD_DEVIATION:
	    case XTRACT_AVERAGE_DEVIATION:
	    case XTRACT_SPECTRAL_VARIANCE:
	    case XTRACT_SPECTRAL_STANDARD_DEVIATION:
	    case XTRACT_SPECTRAL_AVERAGE_DEVIATION:
	    case XTRACT_SPECTRAL_INHARMONICITY:
	    case XTRACT_LOWEST_VALUE:
	    case XTRACT_F0:
	    case XTRACT_FAILSAFE_F0:
	    case XTRACT_TONALITY:
		*argc = 1;
		*argv_type = XTRACT_FLOAT;
		break;
	    case XTRACT_SKEWNESS:
	    case XTRACT_KURTOSIS:
	    case XTRACT_SPECTRAL_SKEWNESS:
	    case XTRACT_SPECTRAL_KURTOSIS:
	    case XTRACT_SPECTRUM:
	    case XTRACT_PEAK_SPECTRUM:
	    case XTRACT_HARMONIC_SPECTRUM:
	    case XTRACT_NOISINESS:
	    case XTRACT_CREST:
	    case XTRACT_ROLLOFF:
		*argc = 2;
		*argv_type = XTRACT_FLOAT;
		break;
	    case XTRACT_MFCC:
		*argc = 1;
		*argv_type = XTRACT_MEL_FILTER;
		break;
	    case XTRACT_BARK_COEFFICIENTS:
		*argc = XTRACT_BARK_BANDS;
		*argv_type = XTRACT_INT;
		break;
	    case XTRACT_MEAN:
	    case XTRACT_SPECTRAL_MEAN:
	    case XTRACT_SPECTRAL_CENTROID:
	    case XTRACT_IRREGULARITY_K:
	    case XTRACT_IRREGULARITY_J:
	    case XTRACT_TRISTIMULUS_1:
	    case XTRACT_TRISTIMULUS_2:
	    case XTRACT_TRISTIMULUS_3:
	    case XTRACT_SMOOTHNESS:
	    case XTRACT_FLATNESS:
	    case XTRACT_SPREAD:
	    case XTRACT_ZCR:
	    case XTRACT_LOUDNESS:
	    case XTRACT_HIGHEST_VALUE:
	    case XTRACT_SUM:
	    case XTRACT_RMS_AMPLITUDE:
	    case XTRACT_POWER:
	    case XTRACT_SHARPNESS:
	    case XTRACT_SPECTRAL_SLOPE:
	    case XTRACT_HPS:
	    case XTRACT_FLUX: 
	    case XTRACT_ATTACK_TIME: 
	    case XTRACT_DECAY_TIME: 
	    case XTRACT_DELTA_FEATURE: 
	    case XTRACT_AUTOCORRELATION_FFT:
	    case XTRACT_DCT:
	    case XTRACT_AUTOCORRELATION:
	    case XTRACT_AMDF:
	    case XTRACT_ASDF:
	    case XTRACT_NONZERO_COUNT:
	    case XTRACT_ODD_EVEN_RATIO:
	    default:
		*argc = 0;
		break;
	}
		
	argv_min = &d->argv.min[0];
	argv_max = &d->argv.max[0];
	argv_def = &d->argv.def[0];
	argv_unit = &d->argv.unit[0];

	switch (f) {
	    /* argc = 1 */
	    case XTRACT_VARIANCE:
	    case XTRACT_SPECTRAL_VARIANCE:
	    case XTRACT_STANDARD_DEVIATION:
	    case XTRACT_AVERAGE_DEVIATION:
	    case XTRACT_SPECTRAL_STANDARD_DEVIATION:
	    case XTRACT_SPECTRAL_AVERAGE_DEVIATION:
	    case XTRACT_LOWEST_VALUE:
	    case XTRACT_TONALITY:
	    case XTRACT_MFCC:
	    case XTRACT_LPC:
	    case XTRACT_LPCC:
		*argv_min = XTRACT_ANY;
		*argv_max = XTRACT_ANY;
		*argv_def = XTRACT_ANY;
		*argv_unit = XTRACT_ANY;
                break;
	    case XTRACT_SPECTRAL_INHARMONICITY:
		*argv_min = 0.f;
		*argv_max = XTRACT_SR_UPPER_LIMIT / 2;
		*argv_def = XTRACT_FUNDAMENTAL_DEFAULT;
		*argv_unit = XTRACT_HERTZ;
                break;
	    case XTRACT_F0:
	    case XTRACT_FAILSAFE_F0:
		*argv_min = XTRACT_SR_LOWER_LIMIT;
		*argv_max = XTRACT_SR_UPPER_LIMIT;
		*argv_def = XTRACT_SR_DEFAULT; 
		*argv_unit = XTRACT_HERTZ;
                break;
	    /* argc = 2 */;
	    case XTRACT_ROLLOFF:
		*argv_min  = XTRACT_FFT_BANDS_MIN;
		*argv_max = XTRACT_FFT_BANDS_MAX;
		*argv_def = XTRACT_SPEC_BW_DEF ;
		*argv_unit = XTRACT_HERTZ;
		*(argv_min + 1) = 0.f;
		*(argv_max + 1) = 100.f;
		*(argv_def + 1) = 95.f;
		*(argv_unit + 1) = XTRACT_PERCENT;
                break;
	    case XTRACT_SPECTRUM:
		*argv_min  = XTRACT_SR_LOWER_LIMIT / 2; 
		*argv_max = XTRACT_SR_UPPER_LIMIT / 2;
		*argv_def = XTRACT_SR_DEFAULT / 2;
		*argv_unit = XTRACT_HERTZ;
		*(argv_min + 1) = 0;
		*(argv_max + 1) = 3 ;
		*(argv_def + 1) = 0;
		*(argv_unit + 1) = XTRACT_NONE;
                break;
	    case XTRACT_PEAK_SPECTRUM:
		*argv_min  = XTRACT_SR_LOWER_LIMIT / 2; 
		*argv_max = XTRACT_SR_UPPER_LIMIT / 2;
		*argv_def = XTRACT_SR_DEFAULT / 2;
		*argv_unit = XTRACT_HERTZ;
		*(argv_min + 1) = 0.f;
		*(argv_max + 1) = 100.f ;
		*(argv_def + 1) = 10.f ;
		*(argv_unit + 1) = XTRACT_PERCENT;
                break;
	    case XTRACT_HARMONIC_SPECTRUM:
		*argv_min = 0.f;
		*argv_max = XTRACT_SR_UPPER_LIMIT / 2;
		*argv_def = XTRACT_FUNDAMENTAL_DEFAULT;
		*argv_unit = XTRACT_HERTZ;
		*(argv_min + 1) = 0.f;
		*(argv_max + 1) = 1.f ;
		*(argv_def + 1) = .1f ;
		*(argv_unit + 1) = XTRACT_NONE;
                break;
	    case XTRACT_NOISINESS:
	    case XTRACT_SKEWNESS:
	    case XTRACT_KURTOSIS:
	    case XTRACT_SPECTRAL_SKEWNESS:
	    case XTRACT_SPECTRAL_KURTOSIS:
	    case XTRACT_CREST:
		*argv_min = XTRACT_NONE;
		*argv_max = XTRACT_NONE;
		*argv_def = XTRACT_NONE;
		*argv_unit = XTRACT_NONE;
		*(argv_min + 1) = XTRACT_NONE;
		*(argv_max + 1) = XTRACT_NONE;
		*(argv_def + 1) = XTRACT_NONE;
		*(argv_unit + 1) = XTRACT_NONE;
                break;
	    case XTRACT_BARK_COEFFICIENTS:
	    /* BARK_COEFFICIENTS is special because argc = BARK_BANDS */
	    default:
		*argv_min = XTRACT_NONE;
		*argv_max = XTRACT_NONE;
		*argv_def = XTRACT_NONE;
		*argv_unit = XTRACT_NONE;
                break;
	}

	argv_donor = &d->argv.donor[0];

	switch (f) {
	    /* argc = 1 */
	    case XTRACT_VARIANCE:
		*argv_donor = XTRACT_MEAN;
		break;
	    case XTRACT_SPECTRAL_VARIANCE:
		*argv_donor = XTRACT_SPECTRAL_MEAN;
		break;
	    case XTRACT_STANDARD_DEVIATION:
		*argv_donor = XTRACT_VARIANCE;
		break;
	    case XTRACT_AVERAGE_DEVIATION:
		*argv_donor = XTRACT_MEAN;
		break;
	    case XTRACT_SPECTRAL_STANDARD_DEVIATION:
		*argv_donor = XTRACT_SPECTRAL_VARIANCE;
		break;
	    case XTRACT_SPECTRAL_AVERAGE_DEVIATION:
		*argv_donor = XTRACT_SPECTRAL_MEAN;
		break;
	    case XTRACT_SPECTRAL_INHARMONICITY:
		*argv_donor = XTRACT_FAILSAFE_F0;
		break;
	    case XTRACT_TONALITY:
		*argv_donor = XTRACT_FLATNESS;
		break;
	    case XTRACT_LOWEST_VALUE:
	    case XTRACT_F0:
	    case XTRACT_FAILSAFE_F0:
		*argv_donor = XTRACT_ANY;
		break;
	    case XTRACT_MFCC:
		*argv_donor = XTRACT_INIT_MFCC;
		break;
	    /* argc = 2 */;
	    case XTRACT_SPECTRUM:
	    case XTRACT_ROLLOFF:
	    case XTRACT_PEAK_SPECTRUM:
		*argv_donor = XTRACT_ANY;
		*(argv_donor + 1) = XTRACT_ANY;
		break;
	    case XTRACT_SKEWNESS:
	    case XTRACT_KURTOSIS:
		*argv_donor = XTRACT_MEAN;
		*(argv_donor + 1) = XTRACT_STANDARD_DEVIATION;
		break;
	    case XTRACT_SPECTRAL_SKEWNESS:
	    case XTRACT_SPECTRAL_KURTOSIS:
		*argv_donor = XTRACT_SPECTRAL_MEAN;
		*(argv_donor + 1) = XTRACT_SPECTRAL_STANDARD_DEVIATION;
		break;
	    case XTRACT_HARMONIC_SPECTRUM:
		*argv_donor = XTRACT_FAILSAFE_F0;
		*(argv_donor + 1) = XTRACT_ANY;
		break;
	    case XTRACT_NOISINESS:
		*argv_donor = XTRACT_SUM;
		*(argv_donor + 1) = XTRACT_SUM;
		break;
	    case XTRACT_CREST:
		*argv_donor = XTRACT_HIGHEST_VALUE;
		*(argv_donor + 1) = XTRACT_MEAN;
		break;
	    /* argc = BARK_BANDS */
	    case XTRACT_BARK_COEFFICIENTS:
		*argv_donor = XTRACT_INIT_BARK;
		break;
	    default:
		*argv_donor = XTRACT_ANY;
		break;
	}

        data_format = &d->data.format;

	switch(f){

	    case XTRACT_MEAN: 
	    case XTRACT_VARIANCE:
	    case XTRACT_STANDARD_DEVIATION:
	    case XTRACT_AVERAGE_DEVIATION:
	    case XTRACT_SKEWNESS:
	    case XTRACT_KURTOSIS:
	    case XTRACT_LOWEST_VALUE:
	    case XTRACT_HIGHEST_VALUE:
	    case XTRACT_SUM:
		*data_format = XTRACT_ARBITRARY_SERIES;
		break;
	    case XTRACT_SPECTRAL_MEAN:
	    case XTRACT_SPECTRAL_VARIANCE:
	    case XTRACT_SPECTRAL_STANDARD_DEVIATION:
	    case XTRACT_SPECTRAL_AVERAGE_DEVIATION:
	    case XTRACT_SPECTRAL_SKEWNESS:
	    case XTRACT_SPECTRAL_KURTOSIS:
	    case XTRACT_SPECTRAL_CENTROID:
	    case XTRACT_SPECTRAL_SLOPE:
	        *data_format = XTRACT_SPECTRAL;     
		break;
	    case XTRACT_ROLLOFF:
	    case XTRACT_NOISINESS:
	    case XTRACT_BARK_COEFFICIENTS:
	    case XTRACT_CREST:
	    case XTRACT_IRREGULARITY_K:
	    case XTRACT_IRREGULARITY_J:
	    case XTRACT_SMOOTHNESS:
	    case XTRACT_FLATNESS:
	    case XTRACT_SPREAD:
	    case XTRACT_POWER:
	    case XTRACT_HPS:
	    case XTRACT_PEAK_SPECTRUM:
	    case XTRACT_MFCC:
		*data_format = XTRACT_SPECTRAL_MAGNITUDES;
		break;
            case XTRACT_LPC:
                *data_format = XTRACT_AUTOCORRELATION_COEFFS;
                break;
            case XTRACT_LPCC:
                *data_format = XTRACT_LPC_COEFFS;
                break;
	    case XTRACT_SPECTRAL_INHARMONICITY:
	    case XTRACT_HARMONIC_SPECTRUM:
		*data_format = XTRACT_SPECTRAL_PEAKS;
		break;
	    case XTRACT_NONZERO_COUNT:
		*data_format = XTRACT_SPECTRAL_PEAKS_MAGNITUDES;
		break;
	    case XTRACT_F0:
	    case XTRACT_FAILSAFE_F0:
	    case XTRACT_SPECTRUM:
	    case XTRACT_AUTOCORRELATION:
	    case XTRACT_AUTOCORRELATION_FFT:
	    case XTRACT_DCT:
	    case XTRACT_AMDF:
	    case XTRACT_ASDF:
	    case XTRACT_ZCR:
	    case XTRACT_RMS_AMPLITUDE:
		*data_format = XTRACT_AUDIO_SAMPLES;
		break;
	    case XTRACT_TONALITY:
		*data_format = XTRACT_NO_DATA;
		break;
	    case XTRACT_TRISTIMULUS_1:
	    case XTRACT_TRISTIMULUS_2:
	    case XTRACT_TRISTIMULUS_3:
	    case XTRACT_ODD_EVEN_RATIO:
		*data_format = XTRACT_SPECTRAL_HARMONICS_MAGNITUDES;
		break;
	    case XTRACT_LOUDNESS:
	    case XTRACT_SHARPNESS:
		*data_format = XTRACT_BARK_COEFFS;
		break;
	    case XTRACT_FLUX: 
	    case XTRACT_ATTACK_TIME: 
	    case XTRACT_DECAY_TIME: 
	    case XTRACT_DELTA_FEATURE: 
	    default:
		*data_format = XTRACT_NO_DATA;
		break;
	}

        data_unit = &d->data.unit;

	switch(f){

	    case XTRACT_MEAN: 
	    case XTRACT_VARIANCE:
	    case XTRACT_STANDARD_DEVIATION:
	    case XTRACT_AVERAGE_DEVIATION:
	    case XTRACT_SKEWNESS:
	    case XTRACT_KURTOSIS:
	    case XTRACT_LOWEST_VALUE:
	    case XTRACT_HIGHEST_VALUE:
	    case XTRACT_SUM:
	    case XTRACT_ZCR:
	    case XTRACT_PEAK_SPECTRUM:
	    case XTRACT_TRISTIMULUS_1:
	    case XTRACT_TRISTIMULUS_2:
	    case XTRACT_TRISTIMULUS_3:
	    case XTRACT_DCT:
	    case XTRACT_AMDF:
	    case XTRACT_ASDF:
	    case XTRACT_IRREGULARITY_K:
	    case XTRACT_IRREGULARITY_J:
	    case XTRACT_ATTACK_TIME: 
	    case XTRACT_DECAY_TIME: 
	    case XTRACT_DELTA_FEATURE: 
	    case XTRACT_FLUX: 
	    case XTRACT_F0:
	    case XTRACT_FAILSAFE_F0:
	    case XTRACT_MFCC:
	    case XTRACT_AUTOCORRELATION:
	    case XTRACT_AUTOCORRELATION_FFT:
	    case XTRACT_ROLLOFF:
	    case XTRACT_NOISINESS:
	    case XTRACT_CREST:
	    case XTRACT_FLATNESS:
	    case XTRACT_POWER:
	    case XTRACT_BARK_COEFFICIENTS:
	    case XTRACT_RMS_AMPLITUDE:
	    case XTRACT_SMOOTHNESS:
	    case XTRACT_SPREAD:
	    case XTRACT_SHARPNESS:
	    case XTRACT_HPS:
	    case XTRACT_SPECTRUM:
	    case XTRACT_TONALITY:
	    case XTRACT_LOUDNESS:
	    case XTRACT_NONZERO_COUNT:
            case XTRACT_LPC:
            case XTRACT_LPCC:
		*data_unit = XTRACT_ANY;
		break;
	    case XTRACT_SPECTRAL_MEAN:
	    case XTRACT_SPECTRAL_VARIANCE:
	    case XTRACT_SPECTRAL_STANDARD_DEVIATION:
	    case XTRACT_SPECTRAL_AVERAGE_DEVIATION:
	    case XTRACT_SPECTRAL_SKEWNESS:
	    case XTRACT_SPECTRAL_KURTOSIS:
	    case XTRACT_SPECTRAL_CENTROID:
	    case XTRACT_SPECTRAL_SLOPE:
	    case XTRACT_HARMONIC_SPECTRUM:
	    case XTRACT_SPECTRAL_INHARMONICITY:
		*data_unit = XTRACT_ANY_AMPLITUDE_HERTZ;
		break;
	    case XTRACT_ODD_EVEN_RATIO:
		*data_unit = XTRACT_HERTZ;
		break;
	}

	name = d->algo.name;
	p_name = d->algo.p_name;
	desc = d->algo.desc;
	p_desc = d->algo.p_desc;
	author = d->algo.author;
	year = &d->algo.year;

	strcpy(author, "");
	*year = 0;

	switch(f){
	    case XTRACT_MEAN: 
		strcpy(name, "mean");
		strcpy(p_name, "Mean");
		strcpy(desc, "Extract the mean of an input vector");
		strcpy(p_desc, "Extract the mean of a range of values");
		strcpy(author, "");
		d->argv.type = XTRACT_NONE;
		break;
	    case XTRACT_VARIANCE:
		strcpy(name, "variance");
		strcpy(p_name, "Variance");
		strcpy(desc, "Extract the variance of an input vector");
		strcpy(p_desc, "Extract the variance of a range of values");
		strcpy(author, "");
		break;
	    case XTRACT_STANDARD_DEVIATION:
		strcpy(name, "standard_deviation");
		strcpy(p_name, "Standard Deviation");
		strcpy(desc, 
			"Extract the standard deviation of an input vector");
		strcpy(p_desc, 
			"Extract the standard deviation of a range of values");
		strcpy(author, "");
		break;
	    case XTRACT_AVERAGE_DEVIATION:
		strcpy(name, "average_deviation");
		strcpy(p_name, "Average Deviation");
		strcpy(desc, 
			"Extract the average deviation of an input vector");
		strcpy(p_desc, 
			"Extract the average deviation of a range of values");
		strcpy(author, "");
		break;
	    case XTRACT_SKEWNESS:
		strcpy(name, "skewness");
		strcpy(p_name, "Skewness");
		strcpy(desc, 
			"Extract the skewness of an input vector");
		strcpy(p_desc, 
			"Extract the skewness of a range of values");
		strcpy(author, "");
		break;
	    case XTRACT_KURTOSIS:
		strcpy(name, "kurtosis");
		strcpy(p_name, "Kurtosis");
		strcpy(desc, 
			"Extract the kurtosis of an input vector");
		strcpy(p_desc, 
			"Extract the kurtosis of a range of values");
		strcpy(author, "");
		break;
	   case XTRACT_SPECTRAL_MEAN: 
		strcpy(name, "spectral_mean");
		strcpy(p_name, "Spectral Mean");
		strcpy(desc, "Extract the mean of an input spectrum");
		strcpy(p_desc, "Extract the mean of an audio spectrum");
		strcpy(author, "");
		break;
	    case XTRACT_SPECTRAL_VARIANCE:
		strcpy(name, "spectral_variance");
		strcpy(p_name, "Spectral Variance");
		strcpy(desc, "Extract the variance of an input spectrum");
		strcpy(p_desc, "Extract the variance of an audio spectrum");
		strcpy(author, "");
		break;
	    case XTRACT_SPECTRAL_STANDARD_DEVIATION:
		strcpy(name, "spectral_standard_deviation");
		strcpy(p_name, "Spectral Standard Deviation");
		strcpy(desc, 
			"Extract the standard deviation of an input spectrum");
		strcpy(p_desc, 
			"Extract the standard deviation of an audio spectrum");
		strcpy(author, "");
		break;
	    case XTRACT_SPECTRAL_AVERAGE_DEVIATION:
		strcpy(name, "spectral_average_deviation");
		strcpy(p_name, "Spectral Average Deviation");
		strcpy(desc, 
			"Extract the average deviation of an input spectrum");
		strcpy(p_desc, 
			"Extract the average deviation of an audio spectrum");
		strcpy(author, "");
		break;
	    case XTRACT_ROLLOFF:
		strcpy(name, "spectral_rolloff");
		strcpy(p_name, "Spectral Rolloff");
		strcpy(desc, 
			"Extract the rolloff point of a spectrum");
		strcpy(p_desc, 
			"Extract the rolloff point of an audio spectrum");
		strcpy(author, "Bee Suan Ong");
		*year = 2005;
		break;
	    case XTRACT_SPECTRAL_INHARMONICITY:
		strcpy(name, "spectral_inharmonicity");
		strcpy(p_name, "Inharmonicity");
		strcpy(desc, "Extract the inharmonicity of a spectrum");
		strcpy(p_desc, 
			"Extract the inharmonicity of an audio spectrum");
		break;
	    case XTRACT_SPECTRUM:
		strcpy(name, "spectrum");
		strcpy(p_name, "Spectrum");
		strcpy(desc, 
			"Extract the spectrum of an input vector");
		strcpy(p_desc, 
			"Extract the spectrum of an audio signal");
		strcpy(author, "");
		break;
	    case XTRACT_ODD_EVEN_RATIO:
		strcpy(name, "odd_even_ratio");
		strcpy(p_name, "Odd/Even Harmonic Ratio");
		strcpy(desc, 
			"Extract the odd-to-even harmonic ratio of a spectrum");
		strcpy(p_desc, 
		 "Extract the odd-to-even harmonic ratio of an audio spectrum");
		strcpy(author, "");
		break;
	    case XTRACT_LOWEST_VALUE:
		strcpy(name, "lowest_value");
		strcpy(p_name, "Lowest Value");
		strcpy(desc, "Extract the lowest value from an input vector");
		strcpy(p_desc, "Extract the lowest value from a given range");
		strcpy(author, "");
		break;
	    case XTRACT_F0:
		strcpy(name, "f0");
		strcpy(p_name, "Fundamental Frequency");
		strcpy(desc, "Extract the fundamental frequency	of a signal");
		strcpy(p_desc, 
			"Extract the fundamental frequency of an audio signal");
		strcpy(author, "Jamie Bullock");
		break;
	    case XTRACT_FAILSAFE_F0:
		strcpy(name, "failsafe_f0");
		strcpy(p_name, "Fundamental Frequency (failsafe)");
		strcpy(desc, "Extract the fundamental frequency of a signal (failsafe)");
		strcpy(p_desc, 
			"Extract the fundamental frequency of an audio signal (failsafe)");
		strcpy(author, "Jamie Bullock");
		break;
	    case XTRACT_TONALITY:
		strcpy(name, "tonality");
		strcpy(p_name, "Tonality");
		strcpy(desc, "Extract the tonality of a spectrum");
		strcpy(p_desc, "Extract the tonality an audio spectrum");
		strcpy(author, "J. D. Johnston");
		*year = 1988;
		break;
	    case XTRACT_SPECTRAL_SKEWNESS:
		strcpy(name, "spectral_skewness");
		strcpy(p_name, "Spectral Skewness");
		strcpy(desc, "Extract the skewness of an input spectrum");
		strcpy(p_desc, "Extract the skewness of an audio spectrum");
		strcpy(author, "");
		break;
	    case XTRACT_SPECTRAL_KURTOSIS:
		strcpy(name, "spectral_kurtosis");
		strcpy(p_name, "Spectral Kurtosis");
		strcpy(desc, "Extract the kurtosis of an input spectrum");
		strcpy(p_desc, "Extract the kurtosis of an audio spectrum");
		strcpy(author, "");
		break;
	    case XTRACT_PEAK_SPECTRUM:
		strcpy(name, "peak_spectrum");
		strcpy(p_name, "Peak Spectrum");
		strcpy(desc, "Extract the spectral peaks from of a spectrum");
		strcpy(p_desc, 
			"Extract the spectral peaks from an audio spectrum");
		strcpy(author, "");
		break;
	    case XTRACT_HARMONIC_SPECTRUM:
		strcpy(name, "harmonic_spectrum");
		strcpy(p_name, "Harmonic Spectrum");
		strcpy(desc, "Extract the harmonics from a spectrum");
		strcpy(p_desc, "Extract the harmonics from an audio spectrum");
		strcpy(author, "");
		break;
	    case XTRACT_NOISINESS:
		strcpy(name, "noisiness");
		strcpy(p_name, "Noisiness");
		strcpy(desc, "Extract the noisiness of a spectrum");
		strcpy(p_desc, "Extract the noisiness of an audio  spectrum");
		strcpy(author, "Tae Hong Park");
		*year = 2000;
		break;
	    case XTRACT_CREST:
		strcpy(name, "crest");
		strcpy(p_name, "Spectral Crest Measure");
		strcpy(desc, 
			"Extract the spectral crest measure of a spectrum");
		strcpy(p_desc, 
		    "Extract the spectral crest measure of an audio spectrum");
		strcpy(author, "Peeters");
		*year = 2003;
		break;
	    case XTRACT_MFCC:
		strcpy(name, "mfcc");
		strcpy(p_name, "Mel-Frequency Cepstral Coefficients");
		strcpy(desc, "Extract MFCC from a spectrum");
		strcpy(p_desc, "Extract MFCC from an audio spectrum");
		strcpy(author, "Rabiner");
                break;
            case XTRACT_LPC:
		strcpy(name, "lpc");
		strcpy(p_name, "Linear predictive coding coefficients");
		strcpy(desc, "Extract LPC from autocorrelation coefficients");
		strcpy(p_desc, 
                        "Extract LPC from autocorrelation coefficients");
		strcpy(author, 
                        "Rabiner and Juang as implemented by Jutta Degener");
                *year = 1994;
                break;
            case XTRACT_LPCC:
		strcpy(name, "lpcc");
		strcpy(p_name, "Linear predictive coding cepstral coefficients");
		strcpy(desc, "Extract LPC cepstrum from LPC coefficients");
		strcpy(p_desc, 
                        "Extract LPC cepstrum from LPC coefficients");
		strcpy(author, "Rabiner and Juang");
                *year = 1993;
		break;
	    case XTRACT_BARK_COEFFICIENTS:
		strcpy(name, "bark_coefficients");
		strcpy(p_name, "Bark Coefficients");
		strcpy(desc, "Extract bark coefficients from a spectrum");
		strcpy(p_desc, 
			"Extract bark coefficients from an audio spectrum");
		strcpy(author, "");
		break;
	    case XTRACT_SPECTRAL_CENTROID:
		strcpy(name, "spectral_centroid");
		strcpy(p_name, "Spectral Centroid");
		strcpy(desc, "Extract the spectral centroid of a spectrum");
		strcpy(p_desc, 
			"Extract the spectral centroid of an audio spectrum");
		strcpy(author, "");
		break;
	    case XTRACT_IRREGULARITY_K:
		strcpy(name, "irregularity_k");
		strcpy(p_name, "Irregularity I");
		strcpy(desc, "Extract the irregularity (type I) of a spectrum");
		strcpy(p_desc, 
			"Extract the irregularity (type I) of an audio spectrum");
		strcpy(author, "Krimphoff");
		*year = 1994;
		break;
	    case XTRACT_IRREGULARITY_J:
		strcpy(name, "irregularity_j");
		strcpy(p_name, "Irregularity II");
		strcpy(desc, "Extract the irregularity (type II) of a spectrum");
		strcpy(p_desc, 
			"Extract the irregularity (type II) of an audio spectrum");
		strcpy(author, "Jensen");
		*year = 1999;
		break;
	    case XTRACT_TRISTIMULUS_1:
		strcpy(name, "tristimulus_1");
		strcpy(p_name, "Tristimulus I");
		strcpy(desc, "Extract the tristimulus (type I) of a spectrum");
		strcpy(p_desc, 
		    "Extract the tristimulus (type I) of an audio spectrum");
		strcpy(author, "Pollard and Jansson");
		*year = 1982;
		break;
	    case XTRACT_TRISTIMULUS_2:
		strcpy(name, "tristimulus_2");
		strcpy(p_name, "Tristimulus II");
		strcpy(desc, "Extract the tristimulus (type II) of a spectrum");
		strcpy(p_desc, 
		    "Extract the tristimulus (type II) of an audio spectrum");
		strcpy(author, "Pollard and Jansson");
		*year = 1982;
		break;
	    case XTRACT_TRISTIMULUS_3:
		strcpy(name, "tristimulus_3");
		strcpy(p_name, "Tristimulus III");
		strcpy(desc, 
			"Extract the tristimulus (type III) of a spectrum");
		strcpy(p_desc, 
		    "Extract the tristimulus (type III) of an audio spectrum");
		strcpy(author, "Pollard and Jansson");
		*year = 1982;
		break;
	    case XTRACT_SMOOTHNESS:
		strcpy(name, "smoothness");
		strcpy(p_name, "Spectral Smoothness");
		strcpy(desc, "Extract the spectral smoothness of a spectrum");
		strcpy(p_desc, 
			"Extract the spectral smoothness of an audio spectrum");
		strcpy(author, "McAdams");
		*year = 1999;
		break;
	    case XTRACT_FLATNESS:
		strcpy(name, "flatness");
		strcpy(p_name, "Spectral Flatness");
		strcpy(desc, "Extract the spectral flatness of a spectrum");
		strcpy(p_desc, 
			"Extract the spectral flatness of an audio spectrum");
		strcpy(author, "Tristan Jehan");
		*year = 2005;
		break;
	    case XTRACT_SPREAD:
		strcpy(name, "spread");
		strcpy(p_name, "Spectral Spread");
		strcpy(desc, "Extract the spectral spread of a spectrum");
		strcpy(p_desc, 
			"Extract the spectral spread of an audio spectrum");
		strcpy(author, "Norman Casagrande");
		*year = 2005;
		break;
	    case XTRACT_ZCR:
		strcpy(name, "zcr");
		strcpy(p_name, "Zero Crossing Rate");
		strcpy(desc, "Extract the zero crossing rate of a vector");
		strcpy(p_desc, 
			"Extract the zero crossing rate of an audio signal");
		strcpy(author, "");
		break;
	    case XTRACT_LOUDNESS:
		strcpy(name, "loudness");
		strcpy(p_name, "Loudness");
		strcpy(desc, 
			"Extract the loudness of a signal from its spectrum");
		strcpy(p_desc, 
		 "Extract the loudness of an audio signal from its spectrum");
		strcpy(author, "Moore, Glasberg et al");
		*year = 2005;
		break;
	    case XTRACT_HIGHEST_VALUE:
		strcpy(name, "highest_value");
		strcpy(p_name, "Highest Value");
		strcpy(desc, "Extract the highest value from an input vector");
		strcpy(p_desc, "Extract the highest value from a given range");
		strcpy(author, "");
		break;
	    case XTRACT_SUM:
		strcpy(name, "sum");
		strcpy(p_name, "Sum of Values");
		strcpy(desc, 
			"Extract the sum of the values in an input vector");
		strcpy(p_desc, 
			"Extract the sum of the values in a given range");
		strcpy(author, "");
		break;
	    case XTRACT_RMS_AMPLITUDE:
		strcpy(name, "rms_amplitude");
		strcpy(p_name, "RMS Amplitude");
		strcpy(desc, "Extract the RMS amplitude of a signal");
		strcpy(p_desc, "Extract the RMS amplitude of an audio signal");
		strcpy(author, "");
		break;
	    case XTRACT_POWER:
		strcpy(name, "power");
		strcpy(p_name, "Spectral Power");
		strcpy(desc, "Extract the spectral power of a spectrum");
		strcpy(p_desc, 
			"Extract the spectral power of an audio spectrum");
		strcpy(author, "Bee Suan Ong");
		*year = 2005;
		break;
	    case XTRACT_SHARPNESS:
		strcpy(name, "sharpness");
		strcpy(p_name, "Spectral Sharpness");
		strcpy(desc, "Extract the spectral sharpness of a spectrum");
		strcpy(p_desc, 
			"Extract the spectral sharpness of an audio spectrum");
		strcpy(author, "");
		break;
	    case XTRACT_SPECTRAL_SLOPE:
		strcpy(name, "spectral_slope");
		strcpy(p_name, "Spectral Slope");
		strcpy(desc, "Extract the spectral slope of a spectrum");
		strcpy(p_desc, 
			"Extract the spectral slope of an audio spectrum");
		strcpy(author, "");
		break;
	    case XTRACT_HPS:
		strcpy(name, "hps");
		strcpy(p_name, "Harmonic Product Spectrum");
		strcpy(desc, 
			"Extract the harmonic product spectrum of a spectrum");
		strcpy(p_desc, 
		 "Extract the harmonic product spectrum of an audio spectrum");
		strcpy(author, "");
		break;
	    case XTRACT_FLUX: 
		strcpy(name, "flux");
		strcpy(p_name, "Spectral Flux");
		strcpy(desc, "Extract the spectral flux of a spectrum");
		strcpy(p_desc, 
			"Extract the spectral flux of an audio spectrum");
		strcpy(author, "");
		break;
	    case XTRACT_ATTACK_TIME: 
		strcpy(name, "attack_time");
		strcpy(p_name, "Attack Time");
		strcpy(desc, "Extract the attack time of a signal");
		strcpy(p_desc, "Extract the attack time of an audio signal");
		strcpy(author, "");
		break;
	    case XTRACT_DECAY_TIME: 
		strcpy(name, "decay_time");
		strcpy(p_name, "Decay Time");
		strcpy(desc, "Extract the decay time of a signal");
		strcpy(p_desc, "Extract the decay time of an audio signal");
		strcpy(author, "");
		break;
	    case XTRACT_DELTA_FEATURE: 
		strcpy(name, "delta_feature");
		strcpy(p_name, "Delta Feature");
		strcpy(desc, "Extract the time derivative of a feature");
		strcpy(p_desc, "Extract the time derivative of a feature");
		strcpy(author, "");
		break;
	    case XTRACT_AUTOCORRELATION_FFT:
		strcpy(name, "autocorrelation_fft");
		strcpy(p_name, "Autocorrelation (FFT method)");
		strcpy(desc, "Extract the autocorrelation of a signal (fft method)");
		strcpy(p_desc, "Extract the autocorrelation of an audio signal (fft method)");
		strcpy(author, "");
		break;
	    case XTRACT_DCT:
		strcpy(name, "dct");
		strcpy(p_name, "Discrete Cosine Transform");
		strcpy(desc, "Extract the DCT of a signal");
		strcpy(p_desc, "Extract the DCT of an audio signal");
		strcpy(author, "");
		break;
	    case XTRACT_AUTOCORRELATION:
		strcpy(name, "autocorrelation");
		strcpy(p_name, "Autocorrelation");
		strcpy(desc, "Extract the autocorrelation of a signal");
		strcpy(p_desc, 
			"Extract the autocorrelation of an audio signal");
		strcpy(author, "");
		break;
	    case XTRACT_AMDF:
		strcpy(name, "amdf");
		strcpy(p_name, "Average Magnitude Difference Function");
		strcpy(desc, "Extract the AMDF of a signal");
		strcpy(p_desc, "Extract the AMDF of an audio signal");
		strcpy(author, "");
		break;
	    case XTRACT_ASDF:
		strcpy(name, "asdf");
		strcpy(p_name, "Average Squared Difference Function");
		strcpy(desc, "Extract the ASDF of a signal");
		strcpy(p_desc, "Extract the ASDF of an audio signal");
		strcpy(author, "");
		break;
	    case XTRACT_NONZERO_COUNT:
		strcpy(name, "nonzero_count");
		strcpy(p_name, "Non-zero count");
		strcpy(desc, "Extract the number of non-zero elements in the input vector");
		strcpy(p_desc, "Extract the number of non-zero elements in an input spectrum");
		strcpy(author, "");
		break;
	    default:
		strcpy(name, "");
		strcpy(p_name, "");
		strcpy(desc, "");
		strcpy(p_desc, "");
		strcpy(author, "");
		break;
	}


	switch(f){

	    case XTRACT_VARIANCE:
	    case XTRACT_STANDARD_DEVIATION:
	    case XTRACT_AVERAGE_DEVIATION:
	    case XTRACT_SPECTRAL_VARIANCE:
	    case XTRACT_SPECTRAL_STANDARD_DEVIATION:
	    case XTRACT_SPECTRAL_AVERAGE_DEVIATION:
	    case XTRACT_SPECTRAL_INHARMONICITY:
	    case XTRACT_LOWEST_VALUE:
	    case XTRACT_F0:
	    case XTRACT_FAILSAFE_F0:
	    case XTRACT_TONALITY:
		*argc = 1;
		*argv_type = XTRACT_FLOAT;
		break;
	    case XTRACT_SKEWNESS:
	    case XTRACT_KURTOSIS:
	    case XTRACT_SPECTRAL_SKEWNESS:
	    case XTRACT_SPECTRAL_KURTOSIS:
	    case XTRACT_SPECTRUM:
	    case XTRACT_PEAK_SPECTRUM:
	    case XTRACT_HARMONIC_SPECTRUM:
	    case XTRACT_NOISINESS:
	    case XTRACT_CREST:
	    case XTRACT_ROLLOFF:
		*argc = 2;
		*argv_type = XTRACT_FLOAT;
		break;
	    case XTRACT_MFCC:
		*argc = 1;
		*argv_type = XTRACT_MEL_FILTER;
		break;
            case XTRACT_LPCC:
                *argc = 1;
                *argv_type = XTRACT_INT;
                break;
	    case XTRACT_BARK_COEFFICIENTS:
		*argc = XTRACT_BARK_BANDS;
		*argv_type = XTRACT_INT;
		break;
	    case XTRACT_MEAN:
	    case XTRACT_SPECTRAL_MEAN:
	    case XTRACT_SPECTRAL_CENTROID:
	    case XTRACT_IRREGULARITY_K:
	    case XTRACT_IRREGULARITY_J:
	    case XTRACT_TRISTIMULUS_1:
	    case XTRACT_TRISTIMULUS_2:
	    case XTRACT_TRISTIMULUS_3:
	    case XTRACT_SMOOTHNESS:
	    case XTRACT_FLATNESS:
	    case XTRACT_SPREAD:
	    case XTRACT_ZCR:
	    case XTRACT_LOUDNESS:
	    case XTRACT_HIGHEST_VALUE:
	    case XTRACT_SUM:
	    case XTRACT_RMS_AMPLITUDE:
	    case XTRACT_POWER:
	    case XTRACT_SHARPNESS:
	    case XTRACT_SPECTRAL_SLOPE:
	    case XTRACT_HPS:
	    case XTRACT_FLUX: 
	    case XTRACT_ATTACK_TIME: 
	    case XTRACT_DECAY_TIME: 
	    case XTRACT_DELTA_FEATURE: 
	    case XTRACT_AUTOCORRELATION_FFT:
	    case XTRACT_DCT:
	    case XTRACT_AUTOCORRELATION:
	    case XTRACT_AMDF:
	    case XTRACT_ASDF:
	    case XTRACT_NONZERO_COUNT:
	    case XTRACT_ODD_EVEN_RATIO:
            case XTRACT_LPC:
	    default:
		*argc = 0;
		break;
	}
    
	is_scalar = &d->is_scalar;

	switch(f){
	    case XTRACT_MEAN:
	    case XTRACT_VARIANCE:
	    case XTRACT_STANDARD_DEVIATION:
	    case XTRACT_AVERAGE_DEVIATION:
	    case XTRACT_SKEWNESS:
	    case XTRACT_KURTOSIS:
	    case XTRACT_SPECTRAL_MEAN:
	    case XTRACT_SPECTRAL_VARIANCE:
	    case XTRACT_SPECTRAL_STANDARD_DEVIATION:
	    case XTRACT_SPECTRAL_AVERAGE_DEVIATION:
	    case XTRACT_SPECTRAL_SKEWNESS:
	    case XTRACT_SPECTRAL_KURTOSIS:
	    case XTRACT_SPECTRAL_CENTROID:
	    case XTRACT_IRREGULARITY_K:
	    case XTRACT_IRREGULARITY_J:
	    case XTRACT_TRISTIMULUS_1:
	    case XTRACT_TRISTIMULUS_2:
	    case XTRACT_TRISTIMULUS_3:
	    case XTRACT_SMOOTHNESS:
	    case XTRACT_SPREAD:
	    case XTRACT_ZCR:
	    case XTRACT_ROLLOFF:
	    case XTRACT_LOUDNESS:
	    case XTRACT_FLATNESS:
	    case XTRACT_TONALITY:
	    case XTRACT_CREST:
	    case XTRACT_NOISINESS:
	    case XTRACT_RMS_AMPLITUDE:
	    case XTRACT_SPECTRAL_INHARMONICITY:
	    case XTRACT_POWER:
	    case XTRACT_ODD_EVEN_RATIO:
	    case XTRACT_SHARPNESS:
	    case XTRACT_SPECTRAL_SLOPE:
	    case XTRACT_LOWEST_VALUE:
	    case XTRACT_HIGHEST_VALUE:
	    case XTRACT_SUM:
	    case XTRACT_HPS:
	    case XTRACT_F0:
	    case XTRACT_FAILSAFE_F0:
	    case XTRACT_NONZERO_COUNT:
		*is_scalar = XTRACT_TRUE;
		break;
	    case XTRACT_AUTOCORRELATION:
	    case XTRACT_AMDF:
	    case XTRACT_ASDF:
	    case XTRACT_BARK_COEFFICIENTS:
	    case XTRACT_PEAK_SPECTRUM:
	    case XTRACT_SPECTRUM:
	    case XTRACT_AUTOCORRELATION_FFT:
	    case XTRACT_MFCC:
	    case XTRACT_LPC:
	    case XTRACT_LPCC:
	    case XTRACT_DCT:
	    case XTRACT_HARMONIC_SPECTRUM:
		*is_scalar = XTRACT_FALSE;
		break;
	    default:
		*is_scalar = XTRACT_TRUE;
		break;

	}

	if(*is_scalar){

	    result_unit = &d->result.scalar.unit;
	    result_min = &d->result.scalar.min;
	    result_max = &d->result.scalar.max;

	    switch(f){
		case XTRACT_MEAN:
		case XTRACT_VARIANCE:
		case XTRACT_STANDARD_DEVIATION:
		case XTRACT_AVERAGE_DEVIATION:
		case XTRACT_SKEWNESS:
		case XTRACT_KURTOSIS:
		case XTRACT_RMS_AMPLITUDE:
		case XTRACT_LOWEST_VALUE:
		case XTRACT_HIGHEST_VALUE:
		case XTRACT_SUM:
		case XTRACT_NONZERO_COUNT: 
		    *result_unit = XTRACT_ANY;
		    *result_min = XTRACT_ANY;
		    *result_max = XTRACT_ANY;
		    break;
		case XTRACT_SPECTRAL_SKEWNESS:
		case XTRACT_SPECTRAL_KURTOSIS:
		case XTRACT_IRREGULARITY_K:
		case XTRACT_IRREGULARITY_J:
		case XTRACT_TRISTIMULUS_1:
		case XTRACT_TRISTIMULUS_2:
		case XTRACT_TRISTIMULUS_3:
		case XTRACT_NOISINESS:
		case XTRACT_SMOOTHNESS:
		    *result_unit = XTRACT_NONE;
		    *result_min = XTRACT_ANY; /* FIX: need to check these */
		    *result_max = XTRACT_ANY;
		    break;
		case XTRACT_SPECTRAL_MEAN:
		case XTRACT_SPECTRAL_VARIANCE:
		case XTRACT_SPECTRAL_STANDARD_DEVIATION:
		case XTRACT_SPECTRAL_AVERAGE_DEVIATION:
		case XTRACT_SPECTRAL_CENTROID:
		case XTRACT_SPREAD:
		case XTRACT_F0:
		case XTRACT_FAILSAFE_F0:
		case XTRACT_HPS:
		case XTRACT_ROLLOFF:
		    *result_unit = XTRACT_HERTZ;
		    *result_min = 0.f;
		    *result_max = XTRACT_SR_UPPER_LIMIT / 2;
                    break;
		case XTRACT_ZCR:
		    *result_unit = XTRACT_HERTZ;
		    *result_min = 0.f;
		    *result_max = XTRACT_ANY;
                    break;
		case XTRACT_ODD_EVEN_RATIO:
		    *result_unit = XTRACT_NONE;
		    *result_min = 0.f;
		    *result_max = 1.f; 
                    break;
		case XTRACT_LOUDNESS:
		case XTRACT_FLATNESS:
		case XTRACT_TONALITY:
		case XTRACT_CREST:
		case XTRACT_SPECTRAL_INHARMONICITY:
		case XTRACT_POWER:
		case XTRACT_SHARPNESS:
		case XTRACT_SPECTRAL_SLOPE:
                case XTRACT_LPC:
                case XTRACT_LPCC:
		default:
		    *result_unit = XTRACT_UNKNOWN;
		    *result_min = XTRACT_UNKNOWN;
		    *result_max = XTRACT_UNKNOWN; 
                    break;
	    }
	}
	else {

	    result_min = NULL;
	    result_max = NULL;
	    result_unit = &d->result.vector.unit;
	    result_format = &d->result.vector.format;

	    switch(f) {
		case XTRACT_AUTOCORRELATION:
		case XTRACT_AMDF:
		case XTRACT_ASDF:
		case XTRACT_DCT:
		    *result_format = XTRACT_ARBITRARY_SERIES;
		    *result_unit = XTRACT_ANY;
                    break;
		case XTRACT_BARK_COEFFICIENTS:
		    *result_format = XTRACT_BARK_COEFFS;
		    *result_unit = XTRACT_UNKNOWN; /* FIX: check */
                    break;
		case XTRACT_PEAK_SPECTRUM:
		case XTRACT_SPECTRUM:
		case XTRACT_HARMONIC_SPECTRUM:
		    *result_format = XTRACT_SPECTRAL;
		    *result_unit = XTRACT_ANY_AMPLITUDE_HERTZ;
                    break;
		case XTRACT_AUTOCORRELATION_FFT:
                    break;
		case XTRACT_MFCC:
		    *result_format = XTRACT_MEL_COEFFS;
		    *result_unit = XTRACT_UNKNOWN; /* FIX: check */
                    break;
                case XTRACT_LPC:
                    *result_format = XTRACT_LPC_COEFFS;
                    *result_unit = XTRACT_UNKNOWN;
                    break;
                case XTRACT_LPCC:
                    *result_format = XTRACT_LPCC_COEFFS;
                    *result_unit = XTRACT_UNKNOWN;
                    break;
		default:
		    break;
	    }
	}
    }

    return fd;
}

int xtract_free_descriptors(void *fd){

    if (fd != NULL) {
	free(fd);
    }

    return XTRACT_SUCCESS;
}