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 "modules/audio_coding/codecs/ilbc/cb_construct.h"
20
21 #include "modules/audio_coding/codecs/ilbc/defines.h"
22 #include "modules/audio_coding/codecs/ilbc/gain_dequant.h"
23 #include "modules/audio_coding/codecs/ilbc/get_cd_vec.h"
24 #include "rtc_base/sanitizer.h"
25
26 // An arithmetic operation that is allowed to overflow. (It's still undefined
27 // behavior, so not a good idea; this just makes UBSan ignore the violation, so
28 // that our old code can continue to do what it's always been doing.)
29 static inline int32_t RTC_NO_SANITIZE("signed-integer-overflow")
OverflowingAddS32S32ToS32(int32_t a,int32_t b)30 OverflowingAddS32S32ToS32(int32_t a, int32_t b) {
31 return a + b;
32 }
33
34 /*----------------------------------------------------------------*
35 * Construct decoded vector from codebook and gains.
36 *---------------------------------------------------------------*/
37
WebRtcIlbcfix_CbConstruct(int16_t * decvector,const int16_t * index,const int16_t * gain_index,int16_t * mem,size_t lMem,size_t veclen)38 bool WebRtcIlbcfix_CbConstruct(
39 int16_t* decvector, /* (o) Decoded vector */
40 const int16_t* index, /* (i) Codebook indices */
41 const int16_t* gain_index, /* (i) Gain quantization indices */
42 int16_t* mem, /* (i) Buffer for codevector construction */
43 size_t lMem, /* (i) Length of buffer */
44 size_t veclen) { /* (i) Length of vector */
45 size_t j;
46 int16_t gain[CB_NSTAGES];
47 /* Stack based */
48 int16_t cbvec0[SUBL];
49 int16_t cbvec1[SUBL];
50 int16_t cbvec2[SUBL];
51 int32_t a32;
52 int16_t *gainPtr;
53
54 /* gain de-quantization */
55
56 gain[0] = WebRtcIlbcfix_GainDequant(gain_index[0], 16384, 0);
57 gain[1] = WebRtcIlbcfix_GainDequant(gain_index[1], gain[0], 1);
58 gain[2] = WebRtcIlbcfix_GainDequant(gain_index[2], gain[1], 2);
59
60 /* codebook vector construction and construction of total vector */
61
62 /* Stack based */
63 if (!WebRtcIlbcfix_GetCbVec(cbvec0, mem, (size_t)index[0], lMem, veclen))
64 return false; // Failure.
65 if (!WebRtcIlbcfix_GetCbVec(cbvec1, mem, (size_t)index[1], lMem, veclen))
66 return false; // Failure.
67 if (!WebRtcIlbcfix_GetCbVec(cbvec2, mem, (size_t)index[2], lMem, veclen))
68 return false; // Failure.
69
70 gainPtr = &gain[0];
71 for (j=0;j<veclen;j++) {
72 a32 = (*gainPtr++) * cbvec0[j];
73 a32 += (*gainPtr++) * cbvec1[j];
74 a32 = OverflowingAddS32S32ToS32(a32, (*gainPtr) * cbvec2[j]);
75 gainPtr -= 2;
76 decvector[j] = (int16_t)((a32 + 8192) >> 14);
77 }
78
79 return true; // Success.
80 }
81