Asterisk - The Open Source Telephony Project GIT-master-1f1c5bb
Functions
anaFilter.c File Reference
#include <string.h>
#include "iLBC_define.h"
Include dependency graph for anaFilter.c:

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Functions

void anaFilter (float *In, float *a, int len, float *Out, float *mem)
 

Function Documentation

◆ anaFilter()

void anaFilter ( float *  In,
float *  a,
int  len,
float *  Out,
float *  mem 
)

Definition at line 20 of file anaFilter.c.

26 {
27 int i, j;
28 float *po, *pi, *pm, *pa;
29
30 po = Out;
31
32 /* Filter first part using memory from past */
33
34 for (i=0; i<LPC_FILTERORDER; i++) {
35 pi = &In[i];
36 pm = &mem[LPC_FILTERORDER-1];
37 pa = a;
38 *po=0.0;
39
40
41
42
43
44 for (j=0; j<=i; j++) {
45 *po+=(*pa++)*(*pi--);
46 }
47 for (j=i+1; j<LPC_FILTERORDER+1; j++) {
48
49 *po+=(*pa++)*(*pm--);
50 }
51 po++;
52 }
53
54 /* Filter last part where the state is entirely
55 in the input vector */
56
57 for (i=LPC_FILTERORDER; i<len; i++) {
58 pi = &In[i];
59 pa = a;
60 *po=0.0;
61 for (j=0; j<LPC_FILTERORDER+1; j++) {
62 *po+=(*pa++)*(*pi--);
63 }
64 po++;
65 }
66
67 /* Update state vector */
68
69 memcpy(mem, &In[len-LPC_FILTERORDER],
70 LPC_FILTERORDER*sizeof(float));
71 }
static int len(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t buflen)
#define LPC_FILTERORDER
Definition: iLBC_define.h:40
static struct test_val a

References a, len(), and LPC_FILTERORDER.

Referenced by iLBC_encode().