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_CbConstruct.c
16
17 ******************************************************************/
18
19 #include "cb_construct.h"
20
21 #include "defines.h"
22 #include "gain_dequant.h"
23 #include "get_cd_vec.h"
24
25 /*----------------------------------------------------------------*
26 * Construct decoded vector from codebook and gains.
27 *---------------------------------------------------------------*/
28
WebRtcIlbcfix_CbConstruct(int16_t * decvector,const int16_t * index,const int16_t * gain_index,int16_t * mem,size_t lMem,size_t veclen)29 bool WebRtcIlbcfix_CbConstruct(
30 int16_t* decvector, /* (o) Decoded vector */
31 const int16_t* index, /* (i) Codebook indices */
32 const int16_t* gain_index, /* (i) Gain quantization indices */
33 int16_t* mem, /* (i) Buffer for codevector construction */
34 size_t lMem, /* (i) Length of buffer */
35 size_t veclen) { /* (i) Length of vector */
36 size_t j;
37 int16_t gain[CB_NSTAGES];
38 /* Stack based */
39 int16_t cbvec0[SUBL];
40 int16_t cbvec1[SUBL];
41 int16_t cbvec2[SUBL];
42 int32_t a32;
43 int16_t *gainPtr;
44
45 /* gain de-quantization */
46
47 gain[0] = WebRtcIlbcfix_GainDequant(gain_index[0], 16384, 0);
48 gain[1] = WebRtcIlbcfix_GainDequant(gain_index[1], gain[0], 1);
49 gain[2] = WebRtcIlbcfix_GainDequant(gain_index[2], gain[1], 2);
50
51 /* codebook vector construction and construction of total vector */
52
53 /* Stack based */
54 if (!WebRtcIlbcfix_GetCbVec(cbvec0, mem, (size_t)index[0], lMem, veclen))
55 return false; // Failure.
56 if (!WebRtcIlbcfix_GetCbVec(cbvec1, mem, (size_t)index[1], lMem, veclen))
57 return false; // Failure.
58 if (!WebRtcIlbcfix_GetCbVec(cbvec2, mem, (size_t)index[2], lMem, veclen))
59 return false; // Failure.
60
61 gainPtr = &gain[0];
62 for (j=0;j<veclen;j++) {
63 a32 = (*gainPtr++) * cbvec0[j];
64 a32 += (*gainPtr++) * cbvec1[j];
65 a32 += (*gainPtr) * cbvec2[j];
66 gainPtr -= 2;
67 decvector[j] = (int16_t)((a32 + 8192) >> 14);
68 }
69
70 return true; // Success.
71 }
72