FreeCalypso > hg > gsm-codec-lib

annotate libtwamr/prm2bits.c @ 478:936a08cc73ce

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doc/AMR-library-API: describe the decoder
author Mychaela Falconia <falcon@freecalypso.org>
date Sun, 19 May 2024 21:32:31 +0000
parents ffd48f0a2ab5
children
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1 /*
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2 * A cleaner reimplementation of AMR Prm2bits() function.
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3 */
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4
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5 #include "typedef.h"
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6 #include "namespace.h"
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7 #include "bitno.h"
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8 #include "prm2bits.h"
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9
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10 void Prm2bits(enum Mode mode, const Word16 prm[], Word16 bits[])
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11 {
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12 const Word16 *t = bitno[mode];
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13 unsigned nparam = prmno[mode];
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14 unsigned n, p, mask;
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15 Word16 *b = bits;
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17 for (n = 0; n < nparam; n++) {
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18 p = prm[n];
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19 mask = 1 << (*t++ - 1);
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20 for (; mask; mask >>= 1) {
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21 if (p & mask)
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22 *b++ = 1;
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23 else
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24 *b++ = 0;
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25 }
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26 }
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27 }