FreeCalypso > hg > gsm-codec-lib
annotate libgsmefr/residu.c @ 425:9499d12d315b
libgsmefr/gsm_efr.h: update header comment
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Tue, 07 May 2024 19:18:57 +0000 |
parents | de9dc80c1312 |
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rev | line source |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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1 /************************************************************************* |
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2 * |
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3 * FUNCTION: Residu |
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4 * |
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Mychaela Falconia <falcon@freecalypso.org>
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5 * PURPOSE: Computes the LP residual. |
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Mychaela Falconia <falcon@freecalypso.org>
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6 * |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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7 * DESCRIPTION: |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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8 * The LP residual is computed by filtering the input speech through |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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9 * the LP inverse filter A(z). |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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10 * |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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11 *************************************************************************/ |
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12 |
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13 #include "gsm_efr.h" |
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14 #include "typedef.h" |
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15 #include "namespace.h" |
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16 #include "basic_op.h" |
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parents:
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17 #include "no_count.h" |
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libgsmefr: residu.c compiles
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18 #include "sig_proc.h" |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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19 |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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20 /* m = LPC order == 10 */ |
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21 #define m 10 |
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Mychaela Falconia <falcon@freecalypso.org>
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22 |
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Mychaela Falconia <falcon@freecalypso.org>
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23 void Residu ( |
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Mychaela Falconia <falcon@freecalypso.org>
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24 Word16 a[], /* (i) : prediction coefficients */ |
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25 Word16 x[], /* (i) : speech signal */ |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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26 Word16 y[], /* (o) : residual signal */ |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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27 Word16 lg /* (i) : size of filtering */ |
49dd1ac8e75b
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Mychaela Falconia <falcon@freecalypso.org>
parents:
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28 ) |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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29 { |
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Mychaela Falconia <falcon@freecalypso.org>
parents:
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30 Word16 i, j; |
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31 Word32 s; |
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Mychaela Falconia <falcon@freecalypso.org>
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32 |
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33 for (i = 0; i < lg; i++) |
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Mychaela Falconia <falcon@freecalypso.org>
parents:
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34 { |
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Mychaela Falconia <falcon@freecalypso.org>
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35 s = L_mult (x[i], a[0]); |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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36 for (j = 1; j <= m; j++) |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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37 { |
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Mychaela Falconia <falcon@freecalypso.org>
parents:
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38 s = L_mac (s, a[j], x[i - j]); |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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39 } |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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40 s = L_shl (s, 3); |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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41 y[i] = round (s); move16 (); |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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42 } |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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43 return; |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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44 } |