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comparison libgsmefr/pre_proc.c @ 84:3ea19a9aa2a1

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libgsmefr: pre_proc.c compiles
author Mychaela Falconia <falcon@freecalypso.org>
date Sat, 26 Nov 2022 07:30:53 +0000
parents 49dd1ac8e75b
children
comparison
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83:33714b36841a 84:3ea19a9aa2a1
8 * - 2nd order high pass filtering with cut off frequency at 80 Hz. 8 * - 2nd order high pass filtering with cut off frequency at 80 Hz.
9 * - Divide input by two. 9 * - Divide input by two.
10 * 10 *
11 *************************************************************************/ 11 *************************************************************************/
12 12
13 #include "gsm_efr.h"
13 #include "typedef.h" 14 #include "typedef.h"
15 #include "namespace.h"
14 #include "basic_op.h" 16 #include "basic_op.h"
15 #include "oper_32b.h" 17 #include "oper_32b.h"
16 #include "count.h" 18 #include "no_count.h"
19 #include "sig_proc.h"
20 #include "cnst.h"
21 #include "enc_state.h"
17 22
18 /*------------------------------------------------------------------------* 23 /*------------------------------------------------------------------------*
19 * * 24 * *
20 * Algorithm: * 25 * Algorithm: *
21 * * 26 * *
29 /* filter coefficients (fc = 80 Hz, coeff. b[] is divided by 2) */ 34 /* filter coefficients (fc = 80 Hz, coeff. b[] is divided by 2) */
30 35
31 static const Word16 b[3] = {1899, -3798, 1899}; 36 static const Word16 b[3] = {1899, -3798, 1899};
32 static const Word16 a[3] = {4096, 7807, -3733}; 37 static const Word16 a[3] = {4096, 7807, -3733};
33 38
34 /* Static values to be preserved between calls */
35 /* y[] values are kept in double precision */
36
37 static Word16 y2_hi, y2_lo, y1_hi, y1_lo, x0, x1;
38
39 /* Initialization of static values */ 39 /* Initialization of static values */
40 40
41 void Init_Pre_Process (void) 41 void Init_Pre_Process (struct EFR_encoder_state *st)
42 { 42 {
43 y2_hi = 0; 43 struct preproc_state *pps = &st->pre_proc;
44 y2_lo = 0; 44
45 y1_hi = 0; 45 pps->y2_hi = 0;
46 y1_lo = 0; 46 pps->y2_lo = 0;
47 x0 = 0; 47 pps->y1_hi = 0;
48 x1 = 0; 48 pps->y1_lo = 0;
49 pps->x0 = 0;
50 pps->x1 = 0;
49 } 51 }
50 52
51 void Pre_Process ( 53 void Pre_Process (
54 struct EFR_encoder_state *st,
52 Word16 signal[], /* input/output signal */ 55 Word16 signal[], /* input/output signal */
53 Word16 lg) /* lenght of signal */ 56 Word16 lg) /* lenght of signal */
54 { 57 {
58 struct preproc_state *pps = &st->pre_proc;
55 Word16 i, x2; 59 Word16 i, x2;
56 Word32 L_tmp; 60 Word32 L_tmp;
57 61
58 for (i = 0; i < lg; i++) 62 for (i = 0; i < lg; i++)
59 { 63 {
60 x2 = x1; move16 (); 64 x2 = pps->x1;
61 x1 = x0; move16 (); 65 pps->x1 = pps->x0;
62 x0 = signal[i]; move16 (); 66 pps->x0 = signal[i];
63 67
64 /* y[i] = b[0]*x[i]/2 + b[1]*x[i-1]/2 + b140[2]*x[i-2]/2 */ 68 /* y[i] = b[0]*x[i]/2 + b[1]*x[i-1]/2 + b140[2]*x[i-2]/2 */
65 /* + a[1]*y[i-1] + a[2] * y[i-2]; */ 69 /* + a[1]*y[i-1] + a[2] * y[i-2]; */
66 70
67 L_tmp = Mpy_32_16 (y1_hi, y1_lo, a[1]); 71 L_tmp = Mpy_32_16 (pps->y1_hi, pps->y1_lo, a[1]);
68 L_tmp = L_add (L_tmp, Mpy_32_16 (y2_hi, y2_lo, a[2])); 72 L_tmp = L_add (L_tmp, Mpy_32_16 (pps->y2_hi, pps->y2_lo, a[2]));
69 L_tmp = L_mac (L_tmp, x0, b[0]); 73 L_tmp = L_mac (L_tmp, pps->x0, b[0]);
70 L_tmp = L_mac (L_tmp, x1, b[1]); 74 L_tmp = L_mac (L_tmp, pps->x1, b[1]);
71 L_tmp = L_mac (L_tmp, x2, b[2]); 75 L_tmp = L_mac (L_tmp, x2, b[2]);
72 L_tmp = L_shl (L_tmp, 3); 76 L_tmp = L_shl (L_tmp, 3);
73 signal[i] = round (L_tmp); move16 (); 77 signal[i] = round (L_tmp);
74 78
75 y2_hi = y1_hi; move16 (); 79 pps->y2_hi = pps->y1_hi;
76 y2_lo = y1_lo; move16 (); 80 pps->y2_lo = pps->y1_lo;
77 L_Extract (L_tmp, &y1_hi, &y1_lo); 81 L_Extract (L_tmp, &pps->y1_hi, &pps->y1_lo);
78 } 82 }
79 return; 83 return;
80 } 84 }