annotate amrconv/bitmanip.c @ 493:dc7249923b3a

libgsmhr1: implement TW-TS-002 output
author Mychaela Falconia <falcon@freecalypso.org>
date Mon, 17 Jun 2024 23:00:57 +0000
parents b092a510141e
children
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1 /*
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2 * This module provides two utility functions that serve as building blocks
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3 * for frame bit reordering operations.
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4 */
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5
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6 #include <stdint.h>
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8 msb_get_bit(buf, bn)
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9 uint8_t *buf;
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10 {
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11 int pos_byte = bn >> 3;
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12 int pos_bit = 7 - (bn & 7);
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14 return (buf[pos_byte] >> pos_bit) & 1;
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15 }
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17 msb_set_bit(buf, bn, bit)
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18 uint8_t *buf;
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19 {
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20 int pos_byte = bn >> 3;
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21 int pos_bit = 7 - (bn & 7);
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22
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23 if (bit)
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24 buf[pos_byte] |= (1 << pos_bit);
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25 else
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26 buf[pos_byte] &= ~(1 << pos_bit);
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27 }