FreeCalypso > hg > gsm-codec-lib
annotate libgsmefr/convolve.c @ 56:902bc4b64cc6
libgsmefr: az_lsp.c compiles
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Fri, 25 Nov 2022 17:15:08 +0000 |
parents | 49dd1ac8e75b |
children | 8de2f0f9bd78 |
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 /************************************************************************* |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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2 * |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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3 * FUNCTION: Convolve |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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4 * |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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5 * PURPOSE: |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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6 * Perform the convolution between two vectors x[] and h[] and |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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7 * write the result in the vector y[]. All vectors are of length L |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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8 * and only the first L samples of the convolution are computed. |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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9 * |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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10 * DESCRIPTION: |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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11 * The convolution is given by |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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12 * |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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13 * y[n] = sum_{i=0}^{n} x[i] h[n-i], n=0,...,L-1 |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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14 * |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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15 *************************************************************************/ |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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16 |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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17 #include "typedef.h" |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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18 #include "basic_op.h" |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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19 #include "count.h" |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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20 |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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21 void Convolve ( |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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22 Word16 x[], /* (i) : input vector */ |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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23 Word16 h[], /* (i) : impulse response */ |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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24 Word16 y[], /* (o) : output vector */ |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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25 Word16 L /* (i) : vector size */ |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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26 ) |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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27 { |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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28 Word16 i, n; |
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Mychaela Falconia <falcon@freecalypso.org>
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29 Word32 s; |
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Mychaela Falconia <falcon@freecalypso.org>
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30 |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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31 for (n = 0; n < L; n++) |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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32 { |
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Mychaela Falconia <falcon@freecalypso.org>
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33 s = 0; move32 (); |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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34 for (i = 0; i <= n; i++) |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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35 { |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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36 s = L_mac (s, x[i], h[n - i]); |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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37 } |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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38 s = L_shl (s, 3); |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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39 y[n] = extract_h (s); move16 (); |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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40 } |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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41 |
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libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
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42 return; |
49dd1ac8e75b
libgsmefr: import most *.c files from ETSI source
Mychaela Falconia <falcon@freecalypso.org>
parents:
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43 } |