FreeCalypso > hg > gsm-codec-lib
annotate libgsmefr/preemph.c @ 78:5bc228bb421e
libgsmefr: lsp_az.c compiles
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Sat, 26 Nov 2022 06:54:06 +0000 |
parents | 49dd1ac8e75b |
children | 9aef9e54b19d |
rev | line source |
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49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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1 /*---------------------------------------------------------------------* |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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2 * routine preemphasis() * |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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3 * ~~~~~~~~~~~~~~~~~~~~~ * |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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4 * Preemphasis: filtering through 1 - g z^-1 * |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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5 *---------------------------------------------------------------------*/ |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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6 |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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7 #include "typedef.h" |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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8 #include "basic_op.h" |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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9 #include "count.h" |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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10 |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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11 Word16 mem_pre; |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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12 |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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13 void preemphasis ( |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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14 Word16 *signal, /* (i/o) : input signal overwritten by the output */ |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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15 Word16 g, /* (i) : preemphasis coefficient */ |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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16 Word16 L /* (i) : size of filtering */ |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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17 ) |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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18 { |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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19 Word16 *p1, *p2, temp, i; |
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Mychaela Falconia <falcon@freecalypso.org>
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20 |
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Mychaela Falconia <falcon@freecalypso.org>
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21 p1 = signal + L - 1; move16 (); |
49dd1ac8e75b
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Mychaela Falconia <falcon@freecalypso.org>
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22 p2 = p1 - 1; move16 (); |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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23 temp = *p1; move16 (); |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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24 |
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25 for (i = 0; i <= L - 2; i++) |
49dd1ac8e75b
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Mychaela Falconia <falcon@freecalypso.org>
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26 { |
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Mychaela Falconia <falcon@freecalypso.org>
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27 *p1 = sub (*p1, mult (g, *p2--)); move16 (); |
49dd1ac8e75b
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Mychaela Falconia <falcon@freecalypso.org>
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28 p1--; |
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Mychaela Falconia <falcon@freecalypso.org>
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29 } |
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30 |
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Mychaela Falconia <falcon@freecalypso.org>
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31 *p1 = sub (*p1, mult (g, mem_pre)); move16 (); |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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32 |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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33 mem_pre = temp; move16 (); |
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34 |
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35 return; |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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36 } |