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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7 * the Free Software Foundation; either version 2 of the License, or
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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_scalar.c: defines functions that extract a feature as a single value from an input vector */
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23
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24 #include "xtract/libxtract.h"
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25 #include "math.h"
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26 #include <stdlib.h>
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27
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28 int xtract_mean(float *data, int N, void *argv, float *result){
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29
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30 int n = N;
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31
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32 while(n--)
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33 *result += *data++;
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34
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35 *result /= N;
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36
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37 return SUCCESS;
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38 }
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39
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40 int xtract_variance(float *data, int N, void *argv, float *result){
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41
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42 int n = N;
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43
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44 while(n--)
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45 *result += *data++ - *(float *)argv;
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46
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47 *result = SQ(*result) / (N - 1);
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48
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49 return SUCCESS;
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50 }
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51
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52 int xtract_standard_deviation(float *data, int N, void *argv, float *result){
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53
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54 *result = sqrt(*(float *)argv);
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55
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56 return SUCCESS;
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57 }
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58
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59 int xtract_average_deviation(float *data, int N, void *argv, float *result){
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60
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61 int n = N;
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62
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63 while(n--)
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64 *result += fabs(*data++ - *(float *)argv);
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65
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66 *result /= N;
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67
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68 return SUCCESS;
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69 }
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70
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71 int xtract_skewness(float *data, int N, void *argv, float *result){
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72
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73 int n = N;
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74
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75 while(n--)
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76 *result += (*data++ - ((float *)argv)[0]) / ((float *)argv)[1];
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77
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78 *result = pow(*result, 3) / N;
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79
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80 return SUCCESS;
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81 }
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82
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83 int xtract_kurtosis(float *data, int N, void *argv, float *result){
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84
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85 int n = N;
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86
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87 while(n--)
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88 *result += (*data++ - ((float *)argv)[0]) / ((float *)argv)[1];
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89
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90 *result = pow(*result, 4) / N - 3;
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91
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92 return SUCCESS;
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93 }
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94
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95
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96 int xtract_centroid(float *data, int N, void *argv, float *result){
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97
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98 int n = (N >> 1);
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99
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100 float *freqs, *amps, FA = 0.f, A = 0.f;
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101
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102 freqs = data;
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103 amps = data + n;
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104
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105 while(n--){
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106 FA += freqs[n] * amps[n];
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107 A += amps[n];
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108 }
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109
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110 *result = FA / A;
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111
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112 return SUCCESS;
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113 }
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114
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115 int xtract_irregularity_k(float *data, int N, void *argv, float *result){
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116
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117 int n,
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118 M = N - 1;
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119
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120 for(n = 1; n < M; n++)
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121 *result += abs(data[n] - (data[n-1] + data[n] + data[n+1]) / 3);
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122
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123 return SUCCESS;
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124 }
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125
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126 int xtract_irregularity_j(float *data, int N, void *argv, float *result){
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127
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128 int n = N;
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129
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130 float num = 0.f, den = 0.f;
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131
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132 while(n--){
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133 num += data[n] - data[n+1];
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134 den += data[n] * data[n];
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135 }
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136
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137 *result = num / den;
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138
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139 return SUCCESS;
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140 }
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141
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142 int xtract_tristimulus_1(float *data, int N, void *argv, float *result){
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143
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144 int n = N;
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145
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146 float den = 0.f;
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147
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148 while(n--)
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149 den += data[n];
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150
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151 *result = data[0] / den;
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152
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153 return SUCCESS;
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154 }
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155
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156 int xtract_tristimulus_2(float *data, int N, void *argv, float *result){
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157
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158 int n = N;
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159
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160 float den = 0.f;
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161
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162 while(n--)
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163 den += data[n];
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164
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165 *result = (data[1] + data[2] + data[3]) / den;
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166
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167 return SUCCESS;
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168 }
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169
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170 int xtract_tristimulus_3(float *data, int N, void *argv, float *result){
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171
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172 int n = N;
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173
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174 float den = 0.f, num = 0.f;
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175
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176 while(n--)
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177 den += data[n];
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178
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179 num = den - data[0] + data[1] + data[2] + data[3];
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180
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181 *result = num / den;
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182
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183 return SUCCESS;
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184 }
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185
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186 int xtract_smoothness(float *data, int N, void *argv, float *result){
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187
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188 int n = N;
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189
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190 if (data[0] <= 0) data[0] = 1;
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191 if (data[1] <= 0) data[1] = 1;
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192
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193 for(n = 2; n < N; n++){
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194 if(data[n] <= 0) data[n] = 1;
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195 *result += abs(20 * log(data[n-1]) - (20 * log(data[n-2]) +
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196 20 * log(data[n-1]) + 20 * log(data[n])) / 3);
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197 }
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198
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199 return SUCCESS;
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200 }
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201
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202 int xtract_spread(float *data, int N, void *argv, float *result){
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203
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204 int n = N;
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205
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206 float num = 0.f, den = 0.f, tmp;
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207
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208 while(n--){
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209 tmp = n - *(float *)argv;
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210 num += SQ(tmp) * data[n];
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211 den += data[n];
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212 }
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213
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214 *result = sqrt(num / den);
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215
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216 return SUCCESS;
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217 }
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218
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219 int xtract_zcr(float *data, int N, void *argv, float *result){
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220
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221 int n = N;
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222
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223 for(n = 1; n < N; n++)
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224 if(data[n] * data[n-1] < 0) (*result)++;
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225
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226 *result /= N;
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227
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228 return SUCCESS;
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229 }
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230
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231 int xtract_rolloff(float *data, int N, void *argv, float *result){
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232
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233 int n = N;
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234 float pivot = 0.f, temp = 0.f;
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235
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236 while(n--) pivot += data[n];
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237
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238 pivot *= *(float *)argv;
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239
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240 for(n = 0; temp < pivot; temp += data[n++]);
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241
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242 *result = n;
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243
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244 return SUCCESS;
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245 }
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246
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247 int xtract_loudness(float *data, int N, void *argv, float *result){
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248
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249 int n = BARK_BANDS;
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250
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251 /*if(n != N) return BAD_VECTOR_SIZE; */
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252
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253 while(n--)
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254 *result += pow(data[n], 0.23);
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255
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256 return SUCCESS;
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257 }
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258
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259
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260 int xtract_flatness(float *data, int N, void *argv, float *result){
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261
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262 int n = N;
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263
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264 float num = 0.f, den = 0.f;
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265
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266 while(n--){
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267 if(data[n] !=0){
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268 num *= data[n];
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269 den += data[n];
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270 }
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271 }
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272
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273 num = pow(num, 1 / N);
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274 den /= N;
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275
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276 *result = 10 * log10(num / den);
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277
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278 return SUCCESS;
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279 }
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280
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281 int xtract_tonality(float *data, int N, void *argv, float *result){
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282
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283 float sfmdb, sfm;
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284
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285 sfm = *(float *)argv;
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286
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287 sfmdb = (sfm > 0 ? (10 * log10(sfm)) / -60 : 0);
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288
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289 *result = MIN(sfmdb, 1);
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290
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291 return SUCCESS;
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292 }
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293
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294 int xtract_crest(float *data, int N, void *argv, float *result){
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295
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296 return FEATURE_NOT_IMPLEMENTED;
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297
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298 }
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299
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300 int xtract_noisiness(float *data, int N, void *argv, float *result){
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301
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302 return FEATURE_NOT_IMPLEMENTED;
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303
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304 }
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305
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306 int xtract_rms_amplitude(float *data, int N, void *argv, float *result){
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307
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308 int n = N;
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309
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310 while(n--) *result += SQ(data[n]);
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311
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312 *result = sqrt(*result / N);
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313
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314 return SUCCESS;
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315 }
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316
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317 int xtract_inharmonicity(float *data, int N, void *argv, float *result){
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318
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319 int n = N >> 1;
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320 float num = 0.f, den = 0.f,
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321 fund, *freqs, *amps;
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322
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323 fund = *(float *)argv;
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324 freqs = data;
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325 amps = data + n;
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326
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327 while(n--){
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328 num += abs(freqs[n] - n * fund) * SQ(amps[n]);
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329 den += SQ(amps[n]);
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330 }
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331
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332 *result = (2 * num) / (fund * den);
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333
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334 return SUCCESS;
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335 }
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336
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337
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338 int xtract_power(float *data, int N, void *argv, float *result){
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339
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340 return FEATURE_NOT_IMPLEMENTED;
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341
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342 }
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343
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344 int xtract_odd_even_ratio(float *data, int N, void *argv, float *result){
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345
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346 int n = N, j, k;
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347
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348 float num = 0.f, den = 0.f;
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349
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350 while(n--){
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351 j = n * 2;
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352 k = j - 1;
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353 num += data[k];
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354 den += data[j];
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355 }
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356
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357 *result = num / den;
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358
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359 return SUCCESS;
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360 }
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361
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362 int xtract_sharpness(float *data, int N, void *argv, float *result){
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363
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364 return FEATURE_NOT_IMPLEMENTED;
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365
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366 }
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367
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368 int xtract_slope(float *data, int N, void *argv, float *result){
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369
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370 return FEATURE_NOT_IMPLEMENTED;
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371
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372 }
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373
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374 int xtract_lowest_match(float *data, int N, void *argv, float *result){
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375
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376 float lowest_match = SR_LIMIT;
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377 int n = N;
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378
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379 while(n--) {
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380 if(data[n] > 0)
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381 lowest_match = MIN(lowest_match, data[n]);
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382 }
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383
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384 *result = (lowest_match == SR_LIMIT ? 0 : lowest_match);
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385
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386 return SUCCESS;
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387 }
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388
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389 int xtract_hps(float *data, int N, void *argv, float *result){
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390
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391 int n = N, M, m, l, peak_index, position1_lwr;
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jamie@1
|
392 float *coeffs2, *coeffs3, *product, L,
|
jamie@25
|
393 largest1_lwr, peak, ratio1, sr;
|
jamie@1
|
394
|
jamie@25
|
395 sr = *(float*)argv;
|
jamie@25
|
396
|
jamie@1
|
397 coeffs2 = (float *)malloc(N * sizeof(float));
|
jamie@1
|
398 coeffs3 = (float *)malloc(N * sizeof(float));
|
jamie@1
|
399 product = (float *)malloc(N * sizeof(float));
|
jamie@25
|
400
|
jamie@1
|
401 while(n--) coeffs2[n] = coeffs3[n] = 1;
|
jamie@1
|
402
|
jamie@1
|
403 M = N >> 1;
|
jamie@1
|
404 L = N / 3;
|
jamie@1
|
405
|
jamie@1
|
406 while(M--){
|
jamie@25
|
407 m = M << 1;
|
jamie@25
|
408 coeffs2[M] = (data[m] + data[m+1]) * 0.5f;
|
jamie@1
|
409
|
jamie@25
|
410 if(M < L){
|
jamie@25
|
411 l = M * 3;
|
jamie@25
|
412 coeffs3[M] = (data[l] + data[l+1] + data[l+2]) / 3;
|
jamie@25
|
413 }
|
jamie@1
|
414 }
|
jamie@25
|
415
|
jamie@1
|
416 peak_index = peak = 0;
|
jamie@25
|
417
|
jamie@1
|
418 for(n = 1; n < N; n++){
|
jamie@25
|
419 product[n] = data[n] * coeffs2[n] * coeffs3[n];
|
jamie@25
|
420 if(product[n] > peak){
|
jamie@25
|
421 peak_index = n;
|
jamie@25
|
422 peak = product[n];
|
jamie@25
|
423 }
|
jamie@1
|
424 }
|
jamie@1
|
425
|
jamie@1
|
426 largest1_lwr = position1_lwr = 0;
|
jamie@1
|
427
|
jamie@1
|
428 for(n = 0; n < N; n++){
|
jamie@25
|
429 if(data[n] > largest1_lwr && n != peak_index){
|
jamie@25
|
430 largest1_lwr = data[n];
|
jamie@25
|
431 position1_lwr = n;
|
jamie@25
|
432 }
|
jamie@1
|
433 }
|
jamie@1
|
434
|
jamie@1
|
435 ratio1 = data[position1_lwr] / data[peak_index];
|
jamie@1
|
436
|
jamie@1
|
437 if(position1_lwr > peak_index * 0.4 && position1_lwr <
|
jamie@25
|
438 peak_index * 0.6 && ratio1 > 0.1)
|
jamie@25
|
439 peak_index = position1_lwr;
|
jamie@1
|
440
|
jamie@22
|
441 *result = sr / (float)peak_index;
|
jamie@25
|
442
|
jamie@1
|
443 free(coeffs2);
|
jamie@1
|
444 free(coeffs3);
|
jamie@1
|
445 free(product);
|
jamie@25
|
446
|
jamie@38
|
447 return SUCCESS;
|
jamie@1
|
448 }
|
jamie@5
|
449
|
jamie@5
|
450
|
jamie@5
|
451 int xtract_f0(float *data, int N, void *argv, float *result){
|
jamie@5
|
452
|
jamie@25
|
453 int M, sr, tau, n;
|
jamie@25
|
454 float f0, err_tau_1, err_tau_x, array_max, threshold_peak, threshold_centre;
|
jamie@22
|
455
|
jamie@25
|
456 sr = *(float *)argv;
|
jamie@25
|
457 /* threshold_peak = *((float *)argv+1);
|
jamie@25
|
458 threshold_centre = *((float *)argv+2);
|
jamie@25
|
459 printf("peak: %.2f\tcentre: %.2f\n", threshold_peak, threshold_centre);*/
|
jamie@25
|
460 /* add temporary dynamic control over thresholds to test clipping effects */
|
jamie@22
|
461
|
jamie@25
|
462 /* FIX: tweak and make into macros */
|
jamie@25
|
463 threshold_peak = .8;
|
jamie@25
|
464 threshold_centre = .3;
|
jamie@25
|
465 M = N >> 1;
|
jamie@25
|
466 err_tau_1 = 0;
|
jamie@25
|
467 array_max = 0;
|
jamie@25
|
468
|
jamie@25
|
469 /* Find the array max */
|
jamie@25
|
470 for(n = 0; n < N; n++){
|
jamie@25
|
471 if (data[n] > array_max)
|
jamie@25
|
472 array_max = data[n];
|
jamie@12
|
473 }
|
jamie@25
|
474
|
jamie@25
|
475 threshold_peak *= array_max;
|
jamie@25
|
476
|
jamie@25
|
477 /* peak clip */
|
jamie@25
|
478 for(n = 0; n < N; n++){
|
jamie@25
|
479 if(data[n] > threshold_peak)
|
jamie@25
|
480 data[n] = threshold_peak;
|
jamie@25
|
481 else if(data[n] < -threshold_peak)
|
jamie@25
|
482 data[n] = -threshold_peak;
|
jamie@25
|
483 }
|
jamie@25
|
484
|
jamie@25
|
485 threshold_centre *= array_max;
|
jamie@25
|
486
|
jamie@25
|
487 /* Centre clip */
|
jamie@25
|
488 for(n = 0; n < N; n++){
|
jamie@25
|
489 if (data[n] < threshold_centre)
|
jamie@25
|
490 data[n] = 0;
|
jamie@25
|
491 else
|
jamie@25
|
492 data[n] -= threshold_centre;
|
jamie@25
|
493 }
|
jamie@25
|
494
|
jamie@25
|
495 /* Estimate fundamental freq */
|
jamie@25
|
496 for (n = 1; n < M; n++)
|
jamie@25
|
497 err_tau_1 = err_tau_1 + fabs(data[n] - data[n+1]);
|
jamie@25
|
498 /* FIX: this doesn't pose too much load if it returns 'early', but if it can't find f0, load can be significant for larger block sizes M^2 iterations! */
|
jamie@25
|
499 for (tau = 2; tau < M; tau++){
|
jamie@25
|
500 err_tau_x = 0;
|
jamie@25
|
501 for (n = 1; n < M; n++){
|
jamie@25
|
502 err_tau_x = err_tau_x + fabs(data[n] - data[n+tau]);
|
jamie@25
|
503 }
|
jamie@25
|
504 if (err_tau_x < err_tau_1) {
|
jamie@25
|
505 f0 = sr / (tau + (err_tau_x / err_tau_1));
|
jamie@25
|
506 *result = f0;
|
jamie@25
|
507 return SUCCESS;
|
jamie@25
|
508 }
|
jamie@25
|
509 }
|
jamie@25
|
510 return NO_RESULT;
|
jamie@5
|
511 }
|