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comparison libgsmefr/preemph.c @ 86:9aef9e54b19d

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libgsmefr: preemph.c compiles
author Mychaela Falconia <falcon@freecalypso.org>
date Sat, 26 Nov 2022 09:56:19 +0000
parents 49dd1ac8e75b
children
comparison
equal deleted inserted replaced
85:db8e0b69a6bb 86:9aef9e54b19d
2 * routine preemphasis() * 2 * routine preemphasis() *
3 * ~~~~~~~~~~~~~~~~~~~~~ * 3 * ~~~~~~~~~~~~~~~~~~~~~ *
4 * Preemphasis: filtering through 1 - g z^-1 * 4 * Preemphasis: filtering through 1 - g z^-1 *
5 *---------------------------------------------------------------------*/ 5 *---------------------------------------------------------------------*/
6 6
7 #include "gsm_efr.h"
7 #include "typedef.h" 8 #include "typedef.h"
9 #include "namespace.h"
8 #include "basic_op.h" 10 #include "basic_op.h"
9 #include "count.h" 11 #include "no_count.h"
10 12 #include "sig_proc.h"
11 Word16 mem_pre; 13 #include "cnst.h"
14 #include "dec_state.h"
12 15
13 void preemphasis ( 16 void preemphasis (
17 struct EFR_decoder_state *st,
14 Word16 *signal, /* (i/o) : input signal overwritten by the output */ 18 Word16 *signal, /* (i/o) : input signal overwritten by the output */
15 Word16 g, /* (i) : preemphasis coefficient */ 19 Word16 g, /* (i) : preemphasis coefficient */
16 Word16 L /* (i) : size of filtering */ 20 Word16 L /* (i) : size of filtering */
17 ) 21 )
18 { 22 {
19 Word16 *p1, *p2, temp, i; 23 Word16 *p1, *p2, temp, i;
20 24
21 p1 = signal + L - 1; move16 (); 25 p1 = signal + L - 1;
22 p2 = p1 - 1; move16 (); 26 p2 = p1 - 1;
23 temp = *p1; move16 (); 27 temp = *p1;
24 28
25 for (i = 0; i <= L - 2; i++) 29 for (i = 0; i <= L - 2; i++)
26 { 30 {
27 *p1 = sub (*p1, mult (g, *p2--)); move16 (); 31 *p1 = sub (*p1, mult (g, *p2--));
28 p1--; 32 p1--;
29 } 33 }
30 34
31 *p1 = sub (*p1, mult (g, mem_pre)); move16 (); 35 *p1 = sub (*p1, mult (g, st->mem_pre));
32 36
33 mem_pre = temp; move16 (); 37 st->mem_pre = temp;
34 38
35 return; 39 return;
36 } 40 }