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/*
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
/******************************************************************
iLBC Speech Coder ANSI-C Source Code
WebRtcIlbcfix_CbConstruct.c
******************************************************************/
#include "modules/audio_coding/codecs/ilbc/cb_construct.h"
#include "modules/audio_coding/codecs/ilbc/defines.h"
#include "modules/audio_coding/codecs/ilbc/gain_dequant.h"
#include "modules/audio_coding/codecs/ilbc/get_cd_vec.h"
#include "rtc_base/sanitizer.h"
// An arithmetic operation that is allowed to overflow. (It's still undefined
// behavior, so not a good idea; this just makes UBSan ignore the violation, so
// that our old code can continue to do what it's always been doing.)
static inline int32_t RTC_NO_SANITIZE("signed-integer-overflow")
OverflowingAddS32S32ToS32(int32_t a, int32_t b) {
return a + b;
}
/*----------------------------------------------------------------*
* Construct decoded vector from codebook and gains.
*---------------------------------------------------------------*/
bool WebRtcIlbcfix_CbConstruct(
int16_t* decvector, /* (o) Decoded vector */
const int16_t* index, /* (i) Codebook indices */
const int16_t* gain_index, /* (i) Gain quantization indices */
int16_t* mem, /* (i) Buffer for codevector construction */
size_t lMem, /* (i) Length of buffer */
size_t veclen) { /* (i) Length of vector */
size_t j;
int16_t gain[CB_NSTAGES];
/* Stack based */
int16_t cbvec0[SUBL];
int16_t cbvec1[SUBL];
int16_t cbvec2[SUBL];
int32_t a32;
int16_t *gainPtr;
/* gain de-quantization */
gain[0] = WebRtcIlbcfix_GainDequant(gain_index[0], 16384, 0);
gain[1] = WebRtcIlbcfix_GainDequant(gain_index[1], gain[0], 1);
gain[2] = WebRtcIlbcfix_GainDequant(gain_index[2], gain[1], 2);
/* codebook vector construction and construction of total vector */
/* Stack based */
if (!WebRtcIlbcfix_GetCbVec(cbvec0, mem, (size_t)index[0], lMem, veclen))
return false; // Failure.
if (!WebRtcIlbcfix_GetCbVec(cbvec1, mem, (size_t)index[1], lMem, veclen))
return false; // Failure.
if (!WebRtcIlbcfix_GetCbVec(cbvec2, mem, (size_t)index[2], lMem, veclen))
return false; // Failure.
gainPtr = &gain[0];
for (j=0;j<veclen;j++) {
a32 = (*gainPtr++) * cbvec0[j];
a32 += (*gainPtr++) * cbvec1[j];
a32 = OverflowingAddS32S32ToS32(a32, (*gainPtr) * cbvec2[j]);
gainPtr -= 2;
decvector[j] = (int16_t)((a32 + 8192) >> 14);
}
return true; // Success.
}