webrtc/modules/audio_coding/codecs/ilbc/create_augmented_vec.c
Timothy Gu 3111783aa1 Organize iLBC headers as per style guide
Prior to this commit, most .c files in modules/audio_coding/codecs/ilbc
don't include their corresponding headers, nor do they order #includes
as per the Google Style Guide [1]. The former is especially harmful,
since in C it can silently allow the function signature to diverge from
its prototype, thus causing disaster at runtime.

This CL fixes both issues. In effect, this allows the common_audio and
modules/audio_coding:ilbc targets to be compiled with Clang's
-Wmissing-prototypes, though this CL does not add that change.

[1]: https://google.github.io/styleguide/cppguide.html#Names_and_Order_of_Includes

Bug: webrtc:12314
Change-Id: I8299968ed3cc86ff35d9de045072b846298043af
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/198362
Reviewed-by: Henrik Lundin <henrik.lundin@webrtc.org>
Commit-Queue: Timothy Gu <timothygu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#32896}
2020-12-31 20:57:18 +00:00

83 lines
3.2 KiB
C

/*
* 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_CreateAugmentedVec.c
******************************************************************/
#include "modules/audio_coding/codecs/ilbc/create_augmented_vec.h"
#include "common_audio/signal_processing/include/signal_processing_library.h"
#include "modules/audio_coding/codecs/ilbc/constants.h"
#include "modules/audio_coding/codecs/ilbc/defines.h"
#include "rtc_base/sanitizer.h"
/*----------------------------------------------------------------*
* Recreate a specific codebook vector from the augmented part.
*
*----------------------------------------------------------------*/
void WebRtcIlbcfix_CreateAugmentedVec(
size_t index, /* (i) Index for the augmented vector to be
created */
const int16_t* buffer, /* (i) Pointer to the end of the codebook memory
that is used for creation of the augmented
codebook */
int16_t* cbVec) { /* (o) The constructed codebook vector */
size_t ilow;
const int16_t *ppo, *ppi;
int16_t cbVecTmp[4];
/* Interpolation starts 4 elements before cbVec+index, but must not start
outside |cbVec|; clamping interp_len to stay within |cbVec|.
*/
size_t interp_len = WEBRTC_SPL_MIN(index, 4);
rtc_MsanCheckInitialized(buffer - index - interp_len, sizeof(buffer[0]),
index + interp_len);
ilow = index - interp_len;
/* copy the first noninterpolated part */
ppo = buffer-index;
WEBRTC_SPL_MEMCPY_W16(cbVec, ppo, index);
/* interpolation */
ppo = buffer - interp_len;
ppi = buffer - index - interp_len;
/* perform cbVec[ilow+k] = ((ppi[k]*alphaTbl[k])>>15) +
((ppo[k]*alphaTbl[interp_len-1-k])>>15);
for k = 0..interp_len-1
*/
WebRtcSpl_ElementwiseVectorMult(&cbVec[ilow], ppi, WebRtcIlbcfix_kAlpha,
interp_len, 15);
WebRtcSpl_ReverseOrderMultArrayElements(
cbVecTmp, ppo, &WebRtcIlbcfix_kAlpha[interp_len - 1], interp_len, 15);
WebRtcSpl_AddVectorsAndShift(&cbVec[ilow], &cbVec[ilow], cbVecTmp, interp_len,
0);
/* copy the second noninterpolated part */
ppo = buffer - index;
/* |tempbuff2| is declared in WebRtcIlbcfix_GetCbVec and is SUBL+5 elements
long. |buffer| points one element past the end of that vector, i.e., at
tempbuff2+SUBL+5. Since ppo=buffer-index, we cannot read any more than
|index| elements from |ppo|.
|cbVec| is declared to be SUBL elements long in WebRtcIlbcfix_CbConstruct.
Therefore, we can only write SUBL-index elements to cbVec+index.
These two conditions limit the number of elements to copy.
*/
WEBRTC_SPL_MEMCPY_W16(cbVec+index, ppo, WEBRTC_SPL_MIN(SUBL-index, index));
}