1 /*
2 * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 /******************************************************************
12
13 iLBC Speech Coder ANSI-C Source Code
14
15 WebRtcIlbcfix_GetCbVec.c
16
17 ******************************************************************/
18
19 #include "defines.h"
20 #include "constants.h"
21 #include "create_augmented_vec.h"
22
23 /*----------------------------------------------------------------*
24 * Construct codebook vector for given index.
25 *---------------------------------------------------------------*/
26
WebRtcIlbcfix_GetCbVec(int16_t * cbvec,int16_t * mem,size_t index,size_t lMem,size_t cbveclen)27 void WebRtcIlbcfix_GetCbVec(
28 int16_t *cbvec, /* (o) Constructed codebook vector */
29 int16_t *mem, /* (i) Codebook buffer */
30 size_t index, /* (i) Codebook index */
31 size_t lMem, /* (i) Length of codebook buffer */
32 size_t cbveclen /* (i) Codebook vector length */
33 ){
34 size_t k, base_size;
35 size_t lag;
36 /* Stack based */
37 int16_t tempbuff2[SUBL+5];
38
39 /* Determine size of codebook sections */
40
41 base_size=lMem-cbveclen+1;
42
43 if (cbveclen==SUBL) {
44 base_size += cbveclen / 2;
45 }
46
47 /* No filter -> First codebook section */
48
49 if (index<lMem-cbveclen+1) {
50
51 /* first non-interpolated vectors */
52
53 k=index+cbveclen;
54 /* get vector */
55 WEBRTC_SPL_MEMCPY_W16(cbvec, mem+lMem-k, cbveclen);
56
57 } else if (index < base_size) {
58
59 /* Calculate lag */
60
61 k = (2 * (index - (lMem - cbveclen + 1))) + cbveclen;
62
63 lag = k / 2;
64
65 WebRtcIlbcfix_CreateAugmentedVec(lag, mem+lMem, cbvec);
66
67 }
68
69 /* Higher codebbok section based on filtering */
70
71 else {
72
73 size_t memIndTest;
74
75 /* first non-interpolated vectors */
76
77 if (index-base_size<lMem-cbveclen+1) {
78
79 /* Set up filter memory, stuff zeros outside memory buffer */
80
81 memIndTest = lMem-(index-base_size+cbveclen);
82
83 WebRtcSpl_MemSetW16(mem-CB_HALFFILTERLEN, 0, CB_HALFFILTERLEN);
84 WebRtcSpl_MemSetW16(mem+lMem, 0, CB_HALFFILTERLEN);
85
86 /* do filtering to get the codebook vector */
87
88 WebRtcSpl_FilterMAFastQ12(
89 &mem[memIndTest+4], cbvec, (int16_t*)WebRtcIlbcfix_kCbFiltersRev,
90 CB_FILTERLEN, cbveclen);
91 }
92
93 /* interpolated vectors */
94
95 else {
96 /* Stuff zeros outside memory buffer */
97 memIndTest = lMem-cbveclen-CB_FILTERLEN;
98 WebRtcSpl_MemSetW16(mem+lMem, 0, CB_HALFFILTERLEN);
99
100 /* do filtering */
101 WebRtcSpl_FilterMAFastQ12(
102 &mem[memIndTest+7], tempbuff2, (int16_t*)WebRtcIlbcfix_kCbFiltersRev,
103 CB_FILTERLEN, cbveclen+5);
104
105 /* Calculate lag index */
106 lag = (cbveclen<<1)-20+index-base_size-lMem-1;
107
108 WebRtcIlbcfix_CreateAugmentedVec(lag, tempbuff2+SUBL+5, cbvec);
109 }
110 }
111 }
112