jamie@1
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1 /* libxtract feature extraction library
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2 *
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3 * Copyright (C) 2006 Jamie Bullock
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4 *
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5 * This program is free software; you can redistribute it and/or modify
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6 * it under the terms of the GNU General Public License as published by
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jamie@1
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7 * the Free Software Foundation; either version 2 of the License, or
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jamie@1
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8 * (at your option) any later version.
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9 *
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10 * This program is distributed in the hope that it will be useful,
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11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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13 * GNU General Public License for more details.
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14 *
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15 * You should have received a copy of the GNU General Public License
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16 * along with this program; if not, write to the Free Software
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17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
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18 * USA.
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19 */
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20
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21
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22 /* xtract_vector.c: defines functions that extract a feature as a single value from an input vector */
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23
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jamie@1
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24 #include <math.h>
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jamie@43
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25 #include <string.h>
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jamie@43
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26 #include <stdlib.h>
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jamie@30
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27
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jamie@140
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28 #include "fftsg.h"
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29
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jamie@98
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30 #include "xtract/libxtract.h"
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jamie@98
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31 #include "xtract_macros_private.h"
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32
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jamie@85
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33 #ifndef roundf
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jamie@140
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34 float roundf(float f)
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jamie@140
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35 {
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jamie@140
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36 if (f - (int)f >= 0.5)
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37 return (float)((int)f + 1);
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jamie@140
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38 else
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jamie@140
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39 return (float)((int)f);
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jamie@140
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40 }
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jamie@85
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41 #endif
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42
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jamie@113
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43 #ifndef powf
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jamie@120
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44 #define powf pow
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jamie@113
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45 #endif
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46
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jamie@113
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47 #ifndef expf
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jamie@120
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48 #define expf exp
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49 #endif
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50
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jamie@113
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51 #ifndef sqrtf
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52 #define sqrtf sqrt
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jamie@113
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53 #endif
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54
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jamie@113
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55 #ifndef fabsf
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jamie@120
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56 #define fabsf fabs
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57 #endif
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58
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jamie@98
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59 #include "xtract_globals_private.h"
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jamie@98
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60 #include "xtract_macros_private.h"
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jamie@1
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61
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jamie@140
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62 int xtract_spectrum(const float *data, const int N, const void *argv, float *result)
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jamie@140
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63 {
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jamie@1
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64
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jamie@140
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65 int vector = 0;
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jamie@140
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66 int withDC = 0;
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jamie@140
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67 int normalise = 0;
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jamie@140
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68 float q = 0.f;
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jamie@140
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69 float temp = 0.f;
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jamie@140
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70 float max = 0.f;
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jamie@140
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71 float NxN = XTRACT_SQ(N);
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jamie@140
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72 float *marker = NULL;
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jamie@140
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73 size_t bytes = N * sizeof(double);
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jamie@140
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74 double *rfft = NULL;
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jamie@140
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75 unsigned int n = 0;
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jamie@140
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76 unsigned int m = 0;
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jamie@140
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77 unsigned int nx2 = 0;
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jamie@140
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78 unsigned int M = N >> 1;
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jamie@98
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79
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80 rfft = (double *)malloc(bytes);
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jamie@140
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81 //memcpy(rfft, data, bytes);
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82
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jamie@140
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83 for(n = 0; n < N; ++n){
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jamie@140
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84 rfft[n] = (double)data[n];
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85 }
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86
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87 q = *(float *)argv;
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88 vector = (int)*((float *)argv+1);
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jamie@70
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89 withDC = (int)*((float *)argv+2);
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90 normalise = (int)*((float *)argv+3);
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91
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92 XTRACT_CHECK_q;
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jamie@46
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93
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jamie@140
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94 if(!ooura_data_spectrum.initialised)
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jamie@140
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95 {
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jamie@140
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96 fprintf(stderr,
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jamie@140
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97 "libxtract: error: xtract_spectrum() failed, "
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jamie@140
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98 "fft data unitialised.\n");
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jamie@98
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99 return XTRACT_NO_RESULT;
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jamie@98
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100 }
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jamie@98
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101
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jamie@140
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102 /* ooura is in-place
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103 * the output format seems to be
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104 * a[0] - DC, a[1] - nyquist, a[2...N-1] - remaining bins
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105 */
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jamie@140
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106 rdft(N, 1, rfft, ooura_data_spectrum.ooura_ip,
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107 ooura_data_spectrum.ooura_w);
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108
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109 switch(vector)
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110 {
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111
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jamie@120
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112 case XTRACT_LOG_MAGNITUDE_SPECTRUM:
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113 for(n = 0, m = 0; m < M; ++n, ++m)
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jamie@140
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114 {
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jamie@140
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115 if(!withDC && n == 0)
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116 {
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117 continue;
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118 }
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119 nx2 = n * 2;
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120 temp = XTRACT_SQ(rfft[nx2]) + XTRACT_SQ(rfft[nx2+1]);
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121 if (temp > XTRACT_LOG_LIMIT)
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122 {
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123 temp = logf(sqrtf(temp) / (float)N);
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124 }
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jamie@140
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125 else
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126 {
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127 temp = XTRACT_LOG_LIMIT_DB;
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128 }
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jamie@140
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129 result[m] =
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130 /* Scaling */
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131 (temp + XTRACT_DB_SCALE_OFFSET) /
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132 XTRACT_DB_SCALE_OFFSET;
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133
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134 XTRACT_SET_FREQUENCY;
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135 XTRACT_GET_MAX;
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jamie@140
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136 }
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137 break;
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138
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jamie@140
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139 case XTRACT_POWER_SPECTRUM:
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jamie@140
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140 for(n = 0, m = 0; m < M; ++n, ++m)
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jamie@140
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141 {
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jamie@140
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142 if(!withDC && n == 0)
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jamie@140
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143 {
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jamie@140
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144 ++n;
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jamie@120
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145 }
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jamie@140
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146 result[m] = (XTRACT_SQ(rfft[n]) + XTRACT_SQ(rfft[N - n])) / NxN;
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jamie@140
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147 XTRACT_SET_FREQUENCY;
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148 XTRACT_GET_MAX;
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jamie@140
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149 }
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150 break;
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jamie@120
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151
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jamie@140
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152 case XTRACT_LOG_POWER_SPECTRUM:
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153 for(n = 0, m = 0; m < M; ++n, ++m)
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jamie@140
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154 {
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jamie@140
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155 if(!withDC && n == 0)
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jamie@140
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156 {
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jamie@140
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157 ++n;
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jamie@120
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158 }
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jamie@140
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159 if ((temp = XTRACT_SQ(rfft[n]) + XTRACT_SQ(rfft[N - n])) >
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160 XTRACT_LOG_LIMIT)
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jamie@140
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161 temp = logf(temp / NxN);
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162 else
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163 temp = XTRACT_LOG_LIMIT_DB;
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jamie@67
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164
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165 result[m] = (temp + XTRACT_DB_SCALE_OFFSET) /
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166 XTRACT_DB_SCALE_OFFSET;
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jamie@140
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167 XTRACT_SET_FREQUENCY;
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jamie@140
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168 XTRACT_GET_MAX;
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jamie@140
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169 }
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170 break;
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171
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172 default:
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173 /* MAGNITUDE_SPECTRUM */
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174 for(n = 0, m = 0; m < M; ++n, ++m)
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jamie@140
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175 {
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jamie@140
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176 marker = &result[m];
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jamie@140
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177
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jamie@140
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178 if(n==0 && !withDC) /* discard DC and keep Nyquist */
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179 {
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jamie@140
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180 ++n;
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jamie@140
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181 marker = &result[M-1];
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jamie@120
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182 }
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jamie@140
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183 if(n==1 && withDC) /* discard Nyquist */
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jamie@140
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184 {
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jamie@140
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185 ++n;
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jamie@140
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186 }
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jamie@120
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187
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188 *marker = (float)(sqrt(XTRACT_SQ(rfft[n*2]) +
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189 XTRACT_SQ(rfft[n*2+1])) / (double)N);
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190
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191 XTRACT_SET_FREQUENCY;
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192 XTRACT_GET_MAX;
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193
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194 }
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195 break;
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196 }
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jamie@105
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197
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198 if(normalise)
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199 {
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jamie@105
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200 for(n = 0; n < M; n++)
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jamie@105
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201 result[n] /= max;
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jamie@105
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202 }
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jamie@105
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203
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204 free(rfft);
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jamie@120
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205
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206 return XTRACT_SUCCESS;
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207 }
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208
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209 int xtract_autocorrelation_fft(const float *data, const int N, const void *argv, float *result)
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jamie@140
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210 {
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211
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212 double *rfft = NULL;
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jamie@140
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213 int n = 0;
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214 int M = 0;
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215
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216 M = N << 1;
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217
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218 /* Zero pad the input vector */
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219 rfft = (double *)calloc(M, sizeof(double));
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220 memcpy(rfft, data, N * sizeof(float));
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jamie@75
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221
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222 rdft(M, 1, rfft, ooura_data_autocorrelation_fft.ooura_ip,
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jamie@140
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223 ooura_data_autocorrelation_fft.ooura_w);
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224
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225 for(n = 2; n < M; n++)
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jamie@140
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226 {
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jamie@140
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227 rfft[n*2] = XTRACT_SQ(rfft[n*2]) + XTRACT_SQ(rfft[n*2+1]);
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jamie@140
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228 rfft[n*2+1] = 0.f;
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jamie@75
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229 }
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jamie@120
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230
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jamie@140
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231 rfft[0] = XTRACT_SQ(rfft[0]);
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jamie@140
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232 rfft[1] = XTRACT_SQ(rfft[1]);
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jamie@75
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233
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jamie@140
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234 rdft(M, -1, rfft, ooura_data_autocorrelation_fft.ooura_ip,
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jamie@140
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235 ooura_data_autocorrelation_fft.ooura_w);
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jamie@120
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236
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jamie@75
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237 /* Normalisation factor */
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jamie@75
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238 M = M * N;
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jamie@75
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239
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jamie@75
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240 for(n = 0; n < N; n++)
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jamie@140
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241 result[n] = rfft[n] / (float)M;
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jamie@75
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242
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jamie@140
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243 free(rfft);
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jamie@38
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244
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jamie@56
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245 return XTRACT_SUCCESS;
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jamie@1
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246 }
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jamie@1
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247
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jamie@140
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248 int xtract_mfcc(const float *data, const int N, const void *argv, float *result)
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jamie@140
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249 {
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jamie@30
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250
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jamie@30
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251 xtract_mel_filter *f;
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jamie@30
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252 int n, filter;
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jamie@30
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253
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jamie@30
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254 f = (xtract_mel_filter *)argv;
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jamie@120
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255
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jamie@140
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256 for(filter = 0; filter < f->n_filters; filter++)
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jamie@140
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257 {
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danstowell@68
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258 result[filter] = 0.f;
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jamie@140
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259 for(n = 0; n < N; n++)
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jamie@140
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260 {
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jamie@71
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261 result[filter] += data[n] * f->filters[filter][n];
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jamie@30
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262 }
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jamie@113
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263 result[filter] = logf(result[filter] < XTRACT_LOG_LIMIT ? XTRACT_LOG_LIMIT : result[filter]);
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jamie@30
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264 }
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jamie@30
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265
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jamie@30
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266 xtract_dct(result, f->n_filters, NULL, result);
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jamie@120
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267
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jamie@56
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268 return XTRACT_SUCCESS;
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jamie@30
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269 }
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jamie@30
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270
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jamie@140
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271 int xtract_dct(const float *data, const int N, const void *argv, float *result)
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jamie@140
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272 {
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jamie@120
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273
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jamie@140
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274 int n;
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jamie@140
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275 int m;
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jamie@140
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276 float *temp = calloc(N, sizeof(float));
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jamie@120
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277
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jamie@140
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278 for (n = 0; n < N; ++n)
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jamie@140
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279 {
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jamie@140
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280 for(m = 1; m <= N; ++m) {
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jamie@140
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281 temp[n] += data[m - 1] * cos(M_PI * (n / (float)N) * (m - 0.5));
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jamie@140
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282 }
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jamie@140
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283 }
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jamie@120
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284
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jamie@140
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285 return XTRACT_SUCCESS;
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jamie@30
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286 }
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jamie@30
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287
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jamie@140
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288 int xtract_autocorrelation(const float *data, const int N, const void *argv, float *result)
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jamie@140
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289 {
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jamie@30
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290
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jamie@30
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291 /* Naive time domain implementation */
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jamie@120
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292
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jamie@30
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293 int n = N, i;
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jamie@120
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294
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jamie@30
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295 float corr;
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jamie@30
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296
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jamie@140
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297 while(n--)
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jamie@140
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298 {
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jamie@120
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299 corr = 0;
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jamie@140
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300 for(i = 0; i < N - n; i++)
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jamie@140
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301 {
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jamie@30
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302 corr += data[i] * data[i + n];
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jamie@30
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303 }
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jamie@30
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304 result[n] = corr / N;
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jamie@30
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305 }
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jamie@38
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306
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jamie@56
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307 return XTRACT_SUCCESS;
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jamie@30
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308 }
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jamie@30
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309
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jamie@140
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310 int xtract_amdf(const float *data, const int N, const void *argv, float *result)
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jamie@140
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311 {
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jamie@1
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312
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jamie@1
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313 int n = N, i;
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jamie@120
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314
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jamie@6
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315 float md, temp;
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jamie@1
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316
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jamie@140
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317 while(n--)
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jamie@140
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318 {
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jamie@120
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319 md = 0.f;
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jamie@140
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320 for(i = 0; i < N - n; i++)
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jamie@140
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321 {
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jamie@6
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322 temp = data[i] - data[i + n];
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jamie@120
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323 temp = (temp < 0 ? -temp : temp);
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jamie@120
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324 md += temp;
|
jamie@1
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325 }
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jamie@113
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326 result[n] = md / (float)N;
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jamie@1
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327 }
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jamie@38
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328
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jamie@56
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329 return XTRACT_SUCCESS;
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jamie@1
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330 }
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jamie@1
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331
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jamie@140
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332 int xtract_asdf(const float *data, const int N, const void *argv, float *result)
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jamie@140
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333 {
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jamie@120
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334
|
jamie@1
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335 int n = N, i;
|
jamie@120
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336
|
jamie@1
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337 float sd;
|
jamie@1
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338
|
jamie@140
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339 while(n--)
|
jamie@140
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340 {
|
jamie@120
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341 sd = 0.f;
|
jamie@140
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342 for(i = 0; i < N - n; i++)
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jamie@140
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343 {
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jamie@6
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344 /*sd = 1;*/
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jamie@56
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345 sd += XTRACT_SQ(data[i] - data[i + n]);
|
jamie@1
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346 }
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jamie@113
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347 result[n] = sd / (float)N;
|
jamie@1
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348 }
|
jamie@38
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349
|
jamie@56
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350 return XTRACT_SUCCESS;
|
jamie@1
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351 }
|
jamie@1
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352
|
jamie@140
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353 int xtract_bark_coefficients(const float *data, const int N, const void *argv, float *result)
|
jamie@140
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354 {
|
jamie@1
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355
|
jamie@1
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356 int *limits, band, n;
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jamie@1
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357
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jamie@1
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358 limits = (int *)argv;
|
jamie@120
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359
|
jamie@140
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360 for(band = 0; band < XTRACT_BARK_BANDS - 1; band++)
|
jamie@140
|
361 {
|
jamie@110
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362 result[band] = 0.f;
|
jamie@1
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363 for(n = limits[band]; n < limits[band + 1]; n++)
|
jamie@1
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364 result[band] += data[n];
|
jamie@1
|
365 }
|
jamie@38
|
366
|
jamie@56
|
367 return XTRACT_SUCCESS;
|
jamie@1
|
368 }
|
jamie@1
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369
|
jamie@140
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370 int xtract_peak_spectrum(const float *data, const int N, const void *argv, float *result)
|
jamie@140
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371 {
|
jamie@1
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372
|
jamie@56
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373 float threshold, max, y, y2, y3, p, q, *input = NULL;
|
jamie@43
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374 size_t bytes;
|
jamie@59
|
375 int n = N, rv = XTRACT_SUCCESS;
|
jamie@49
|
376
|
jamie@56
|
377 threshold = max = y = y2 = y3 = p = q = 0.f;
|
jamie@120
|
378
|
jamie@140
|
379 if(argv != NULL)
|
jamie@140
|
380 {
|
jamie@56
|
381 q = ((float *)argv)[0];
|
jamie@55
|
382 threshold = ((float *)argv)[1];
|
jamie@1
|
383 }
|
jamie@49
|
384 else
|
jamie@56
|
385 rv = XTRACT_BAD_ARGV;
|
jamie@49
|
386
|
jamie@140
|
387 if(threshold < 0 || threshold > 100)
|
jamie@140
|
388 {
|
jamie@55
|
389 threshold = 0;
|
jamie@56
|
390 rv = XTRACT_BAD_ARGV;
|
jamie@1
|
391 }
|
jamie@1
|
392
|
jamie@56
|
393 XTRACT_CHECK_q;
|
jamie@49
|
394
|
jamie@98
|
395 input = (float *)calloc(N, sizeof(float));
|
jamie@98
|
396
|
jamie@98
|
397 bytes = N * sizeof(float);
|
jamie@43
|
398
|
jamie@43
|
399 if(input != NULL)
|
jamie@120
|
400 input = memcpy(input, data, bytes);
|
jamie@43
|
401 else
|
jamie@120
|
402 return XTRACT_MALLOC_FAILED;
|
jamie@43
|
403
|
jamie@45
|
404 while(n--)
|
jamie@56
|
405 max = XTRACT_MAX(max, input[n]);
|
jamie@120
|
406
|
jamie@55
|
407 threshold *= .01 * max;
|
jamie@1
|
408
|
jamie@1
|
409 result[0] = 0;
|
jamie@59
|
410 result[N] = 0;
|
jamie@1
|
411
|
jamie@140
|
412 for(n = 1; n < N; n++)
|
jamie@140
|
413 {
|
jamie@140
|
414 if(input[n] >= threshold)
|
jamie@140
|
415 {
|
jamie@140
|
416 if(input[n] > input[n - 1] && n + 1 < N && input[n] > input[n + 1])
|
jamie@140
|
417 {
|
jamie@140
|
418 result[N + n] = q * (n + (p = .5 * ((y = input[n-1]) -
|
jamie@140
|
419 (y3 = input[n+1])) / (input[n - 1] - 2 *
|
jamie@140
|
420 (y2 = input[n]) + input[n + 1])));
|
jamie@52
|
421 result[n] = y2 - .25 * (y - y3) * p;
|
jamie@1
|
422 }
|
jamie@140
|
423 else
|
jamie@140
|
424 {
|
jamie@1
|
425 result[n] = 0;
|
jamie@59
|
426 result[N + n] = 0;
|
jamie@1
|
427 }
|
jamie@1
|
428 }
|
jamie@140
|
429 else
|
jamie@140
|
430 {
|
jamie@1
|
431 result[n] = 0;
|
jamie@59
|
432 result[N + n] = 0;
|
jamie@1
|
433 }
|
jamie@140
|
434 }
|
jamie@120
|
435
|
jamie@43
|
436 free(input);
|
jamie@56
|
437 return (rv ? rv : XTRACT_SUCCESS);
|
jamie@1
|
438 }
|
jamie@120
|
439
|
jamie@140
|
440 int xtract_harmonic_spectrum(const float *data, const int N, const void *argv, float *result)
|
jamie@140
|
441 {
|
jamie@120
|
442
|
jamie@140
|
443 int n = (N >> 1), M = n;
|
jamie@38
|
444
|
jamie@43
|
445 const float *freqs, *amps;
|
jamie@55
|
446 float f0, threshold, ratio, nearest, distance;
|
jamie@38
|
447
|
jamie@52
|
448 amps = data;
|
jamie@52
|
449 freqs = data + n;
|
jamie@38
|
450 f0 = *((float *)argv);
|
jamie@55
|
451 threshold = *((float *)argv+1);
|
jamie@38
|
452
|
jamie@38
|
453 ratio = nearest = distance = 0.f;
|
jamie@38
|
454
|
jamie@140
|
455 while(n--)
|
jamie@140
|
456 {
|
jamie@140
|
457 if(freqs[n])
|
jamie@140
|
458 {
|
jamie@120
|
459 ratio = freqs[n] / f0;
|
jamie@120
|
460 nearest = roundf(ratio);
|
jamie@120
|
461 distance = fabs(nearest - ratio);
|
jamie@120
|
462 if(distance > threshold)
|
jamie@120
|
463 result[n] = result[M + n] = 0.f;
|
jamie@140
|
464 else
|
jamie@140
|
465 {
|
jamie@120
|
466 result[n] = amps[n];
|
jamie@120
|
467 result[M + n] = freqs[n];
|
jamie@120
|
468 }
|
jamie@120
|
469 }
|
jamie@120
|
470 else
|
jamie@120
|
471 result[n] = result[M + n] = 0.f;
|
jamie@38
|
472 }
|
jamie@56
|
473 return XTRACT_SUCCESS;
|
jamie@38
|
474 }
|
jamie@120
|
475
|
jamie@140
|
476 int xtract_lpc(const float *data, const int N, const void *argv, float *result)
|
jamie@140
|
477 {
|
jamie@104
|
478
|
jamie@104
|
479 int i, j, k, M, L;
|
jamie@140
|
480 float r = 0.f,
|
jamie@104
|
481 error = 0.f;
|
jamie@104
|
482
|
jamie@104
|
483 float *ref = NULL,
|
jamie@140
|
484 *lpc = NULL ;
|
jamie@104
|
485
|
jamie@104
|
486 error = data[0];
|
jamie@104
|
487 k = N; /* The length of *data */
|
jamie@104
|
488 L = N - 1; /* The number of LPC coefficients */
|
jamie@104
|
489 M = L * 2; /* The length of *result */
|
jamie@104
|
490 ref = result;
|
jamie@104
|
491 lpc = result+L;
|
jamie@113
|
492
|
jamie@140
|
493 if(error == 0.0)
|
jamie@140
|
494 {
|
jamie@113
|
495 memset(result, 0, M * sizeof(float));
|
jamie@104
|
496 return XTRACT_NO_RESULT;
|
jamie@104
|
497 }
|
jamie@113
|
498
|
jamie@104
|
499 memset(result, 0, M * sizeof(float));
|
jamie@104
|
500
|
jamie@140
|
501 for (i = 0; i < L; i++)
|
jamie@140
|
502 {
|
jamie@104
|
503
|
jamie@104
|
504 /* Sum up this iteration's reflection coefficient. */
|
jamie@104
|
505 r = -data[i + 1];
|
jamie@140
|
506 for (j = 0; j < i; j++)
|
jamie@104
|
507 r -= lpc[j] * data[i - j];
|
jamie@104
|
508 ref[i] = r /= error;
|
jamie@104
|
509
|
jamie@104
|
510 /* Update LPC coefficients and total error. */
|
jamie@104
|
511 lpc[i] = r;
|
jamie@140
|
512 for (j = 0; j < i / 2; j++)
|
jamie@140
|
513 {
|
jamie@104
|
514 float tmp = lpc[j];
|
jamie@104
|
515 lpc[j] = r * lpc[i - 1 - j];
|
jamie@104
|
516 lpc[i - 1 - j] += r * tmp;
|
jamie@104
|
517 }
|
jamie@104
|
518 if (i % 2) lpc[j] += lpc[j] * r;
|
jamie@104
|
519
|
jamie@104
|
520 error *= 1 - r * r;
|
jamie@104
|
521 }
|
jamie@104
|
522
|
jamie@104
|
523 return XTRACT_SUCCESS;
|
jamie@104
|
524 }
|
jamie@104
|
525
|
jamie@140
|
526 int xtract_lpcc(const float *data, const int N, const void *argv, float *result)
|
jamie@140
|
527 {
|
jamie@104
|
528
|
jamie@104
|
529 /* Given N lpc coefficients extract an LPC cepstrum of size argv[0] */
|
jamie@104
|
530 /* Based on an an algorithm by rabiner and Juang */
|
jamie@104
|
531
|
jamie@104
|
532 int n, k;
|
jamie@104
|
533 float sum;
|
jamie@104
|
534 int order = N - 1; /* Eventually change this to Q = 3/2 p as suggested in Rabiner */
|
jamie@140
|
535 int cep_length;
|
jamie@120
|
536
|
jamie@104
|
537 if(argv == NULL)
|
jamie@115
|
538 cep_length = N - 1; /* FIX: if we're going to have default values, they should come from the descriptor */
|
jamie@104
|
539 else
|
jamie@115
|
540 cep_length = *(int *)argv;
|
jamie@120
|
541 //cep_length = (int)((float *)argv)[0];
|
jamie@104
|
542
|
jamie@104
|
543 memset(result, 0, cep_length * sizeof(float));
|
jamie@104
|
544
|
jamie@140
|
545 for (n = 1; n <= order && n <= cep_length; n++)
|
jamie@140
|
546 {
|
jamie@104
|
547 sum = 0.f;
|
jamie@104
|
548 for (k = 1; k < n; k++)
|
jamie@104
|
549 sum += k * result[k-1] * data[n - k];
|
jamie@104
|
550 result[n-1] = data[n] + sum / n;
|
jamie@104
|
551 }
|
jamie@104
|
552
|
jamie@104
|
553 /* be wary of these interpolated values */
|
jamie@140
|
554 for(n = order + 1; n <= cep_length; n++)
|
jamie@140
|
555 {
|
jamie@104
|
556 sum = 0.f;
|
jamie@104
|
557 for (k = n - (order - 1); k < n; k++)
|
jamie@104
|
558 sum += k * result[k-1] * data[n - k];
|
jamie@104
|
559 result[n-1] = sum / n;
|
jamie@104
|
560 }
|
jamie@104
|
561
|
jamie@104
|
562 return XTRACT_SUCCESS;
|
jamie@104
|
563
|
jamie@104
|
564 }
|
jamie@104
|
565 //int xtract_lpcc_s(const float *data, const int N, const void *argv, float *result){
|
jamie@104
|
566 // return XTRACT_SUCCESS;
|
jamie@104
|
567 //}
|
jamie@104
|
568
|
jamie@140
|
569 int xtract_subbands(const float *data, const int N, const void *argv, float *result)
|
jamie@140
|
570 {
|
jamie@104
|
571
|
jamie@114
|
572 int n, bw, xtract_func, nbands, scale, start, lower, *argi, rv;
|
jamie@114
|
573
|
jamie@114
|
574 argi = (int *)argv;
|
jamie@114
|
575
|
jamie@114
|
576 xtract_func = argi[0];
|
jamie@114
|
577 nbands = argi[1];
|
jamie@114
|
578 scale = argi[2];
|
jamie@114
|
579 start = argi[3];
|
jamie@114
|
580
|
jamie@114
|
581 if(scale == XTRACT_LINEAR_SUBBANDS)
|
jamie@114
|
582 bw = floorf((N - start) / nbands);
|
jamie@114
|
583 else
|
jamie@114
|
584 bw = start;
|
jamie@114
|
585
|
jamie@114
|
586 lower = start;
|
jamie@115
|
587 rv = XTRACT_SUCCESS;
|
jamie@114
|
588
|
jamie@140
|
589 for(n = 0; n < nbands; n++)
|
jamie@140
|
590 {
|
jamie@114
|
591
|
jamie@114
|
592 /* Bounds sanity check */
|
jamie@140
|
593 if(lower >= N || lower + bw >= N)
|
jamie@140
|
594 {
|
jamie@120
|
595 // printf("n: %d\n", n);
|
jamie@115
|
596 result[n] = 0.f;
|
jamie@114
|
597 continue;
|
jamie@115
|
598 }
|
jamie@114
|
599
|
jamie@114
|
600 rv = xtract[xtract_func](data+lower, bw, NULL, &result[n]);
|
jamie@114
|
601
|
jamie@114
|
602 if(rv != XTRACT_SUCCESS)
|
jamie@114
|
603 return rv;
|
jamie@114
|
604
|
jamie@140
|
605 switch(scale)
|
jamie@140
|
606 {
|
jamie@140
|
607 case XTRACT_OCTAVE_SUBBANDS:
|
jamie@140
|
608 lower += bw;
|
jamie@140
|
609 bw = lower;
|
jamie@140
|
610 break;
|
jamie@140
|
611 case XTRACT_LINEAR_SUBBANDS:
|
jamie@140
|
612 lower += bw;
|
jamie@140
|
613 break;
|
jamie@114
|
614 }
|
jamie@114
|
615
|
jamie@114
|
616 }
|
jamie@114
|
617
|
jamie@114
|
618 return rv;
|
jamie@114
|
619
|
jamie@114
|
620 }
|
jamie@114
|
621
|
jamie@114
|
622
|
jamie@114
|
623
|