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/*
* Copyright (c) 2012 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.
*/
#include "modules/audio_processing/aecm/echo_control_mobile.h"
#ifdef AEC_DEBUG
#include <stdio.h>
#endif
#include <stdlib.h>
#include <string.h>
extern "C" {
#include "common_audio/ring_buffer.h"
#include "common_audio/signal_processing/include/signal_processing_library.h"
#include "modules/audio_processing/aecm/aecm_defines.h"
}
#include "modules/audio_processing/aecm/aecm_core.h"
namespace webrtc {
namespace {
#define BUF_SIZE_FRAMES 50 // buffer size (frames)
// Maximum length of resampled signal. Must be an integer multiple of frames
// (ceil(1/(1 + MIN_SKEW)*2) + 1)*FRAME_LEN
// The factor of 2 handles wb, and the + 1 is as a safety margin
#define MAX_RESAMP_LEN (5 * FRAME_LEN)
static const size_t kBufSizeSamp =
BUF_SIZE_FRAMES * FRAME_LEN; // buffer size (samples)
static const int kSampMsNb = 8; // samples per ms in nb
// Target suppression levels for nlp modes
// log{0.001, 0.00001, 0.00000001}
static const int kInitCheck = 42;
typedef struct {
int sampFreq;
int scSampFreq;
short bufSizeStart;
int knownDelay;
// Stores the last frame added to the farend buffer
short farendOld[2][FRAME_LEN];
short initFlag; // indicates if AEC has been initialized
// Variables used for averaging far end buffer size
short counter;
short sum;
short firstVal;
short checkBufSizeCtr;
// Variables used for delay shifts
short msInSndCardBuf;
short filtDelay;
int timeForDelayChange;
int ECstartup;
int checkBuffSize;
int delayChange;
short lastDelayDiff;
int16_t echoMode;
#ifdef AEC_DEBUG
FILE* bufFile;
FILE* delayFile;
FILE* preCompFile;
FILE* postCompFile;
#endif // AEC_DEBUG
// Structures
RingBuffer* farendBuf;
AecmCore* aecmCore;
} AecMobile;
} // namespace
// Estimates delay to set the position of the farend buffer read pointer
// (controlled by knownDelay)
static int WebRtcAecm_EstBufDelay(AecMobile* aecm, short msInSndCardBuf);
// Stuffs the farend buffer if the estimated delay is too large
static int WebRtcAecm_DelayComp(AecMobile* aecm);
void* WebRtcAecm_Create() {
// Allocate zero-filled memory.
AecMobile* aecm = static_cast<AecMobile*>(calloc(1, sizeof(AecMobile)));
aecm->aecmCore = WebRtcAecm_CreateCore();
if (!aecm->aecmCore) {
WebRtcAecm_Free(aecm);
return NULL;
}
aecm->farendBuf = WebRtc_CreateBuffer(kBufSizeSamp, sizeof(int16_t));
if (!aecm->farendBuf) {
WebRtcAecm_Free(aecm);
return NULL;
}
#ifdef AEC_DEBUG
aecm->aecmCore->farFile = fopen("aecFar.pcm", "wb");
aecm->aecmCore->nearFile = fopen("aecNear.pcm", "wb");
aecm->aecmCore->outFile = fopen("aecOut.pcm", "wb");
// aecm->aecmCore->outLpFile = fopen("aecOutLp.pcm","wb");
aecm->bufFile = fopen("aecBuf.dat", "wb");
aecm->delayFile = fopen("aecDelay.dat", "wb");
aecm->preCompFile = fopen("preComp.pcm", "wb");
aecm->postCompFile = fopen("postComp.pcm", "wb");
#endif // AEC_DEBUG
return aecm;
}
void WebRtcAecm_Free(void* aecmInst) {
AecMobile* aecm = static_cast<AecMobile*>(aecmInst);
if (aecm == NULL) {
return;
}
#ifdef AEC_DEBUG
fclose(aecm->aecmCore->farFile);
fclose(aecm->aecmCore->nearFile);
fclose(aecm->aecmCore->outFile);
// fclose(aecm->aecmCore->outLpFile);
fclose(aecm->bufFile);
fclose(aecm->delayFile);
fclose(aecm->preCompFile);
fclose(aecm->postCompFile);
#endif // AEC_DEBUG
WebRtcAecm_FreeCore(aecm->aecmCore);
WebRtc_FreeBuffer(aecm->farendBuf);
free(aecm);
}
int32_t WebRtcAecm_Init(void* aecmInst, int32_t sampFreq) {
AecMobile* aecm = static_cast<AecMobile*>(aecmInst);
AecmConfig aecConfig;
if (aecm == NULL) {
return -1;
}
if (sampFreq != 8000 && sampFreq != 16000) {
return AECM_BAD_PARAMETER_ERROR;
}
aecm->sampFreq = sampFreq;
// Initialize AECM core
if (WebRtcAecm_InitCore(aecm->aecmCore, aecm->sampFreq) == -1) {
return AECM_UNSPECIFIED_ERROR;
}
// Initialize farend buffer
WebRtc_InitBuffer(aecm->farendBuf);
aecm->initFlag = kInitCheck; // indicates that initialization has been done
aecm->delayChange = 1;
aecm->sum = 0;
aecm->counter = 0;
aecm->checkBuffSize = 1;
aecm->firstVal = 0;
aecm->ECstartup = 1;
aecm->bufSizeStart = 0;
aecm->checkBufSizeCtr = 0;
aecm->filtDelay = 0;
aecm->timeForDelayChange = 0;
aecm->knownDelay = 0;
aecm->lastDelayDiff = 0;
memset(&aecm->farendOld, 0, sizeof(aecm->farendOld));
// Default settings.
aecConfig.cngMode = AecmTrue;
aecConfig.echoMode = 3;
if (WebRtcAecm_set_config(aecm, aecConfig) == -1) {
return AECM_UNSPECIFIED_ERROR;
}
return 0;
}
// Returns any error that is caused when buffering the
// farend signal.
int32_t WebRtcAecm_GetBufferFarendError(void* aecmInst,
const int16_t* farend,
size_t nrOfSamples) {
AecMobile* aecm = static_cast<AecMobile*>(aecmInst);
if (aecm == NULL)
return -1;
if (farend == NULL)
return AECM_NULL_POINTER_ERROR;
if (aecm->initFlag != kInitCheck)
return AECM_UNINITIALIZED_ERROR;
if (nrOfSamples != 80 && nrOfSamples != 160)
return AECM_BAD_PARAMETER_ERROR;
return 0;
}
int32_t WebRtcAecm_BufferFarend(void* aecmInst,
const int16_t* farend,
size_t nrOfSamples) {
AecMobile* aecm = static_cast<AecMobile*>(aecmInst);
const int32_t err =
WebRtcAecm_GetBufferFarendError(aecmInst, farend, nrOfSamples);
if (err != 0)
return err;
// TODO(unknown): Is this really a good idea?
if (!aecm->ECstartup) {
WebRtcAecm_DelayComp(aecm);
}
WebRtc_WriteBuffer(aecm->farendBuf, farend, nrOfSamples);
return 0;
}
int32_t WebRtcAecm_Process(void* aecmInst,
const int16_t* nearendNoisy,
const int16_t* nearendClean,
int16_t* out,
size_t nrOfSamples,
int16_t msInSndCardBuf) {
AecMobile* aecm = static_cast<AecMobile*>(aecmInst);
int32_t retVal = 0;
size_t i;
short nmbrOfFilledBuffers;
size_t nBlocks10ms;
size_t nFrames;
#ifdef AEC_DEBUG
short msInAECBuf;
#endif
if (aecm == NULL) {
return -1;
}
if (nearendNoisy == NULL) {
return AECM_NULL_POINTER_ERROR;
}
if (out == NULL) {
return AECM_NULL_POINTER_ERROR;
}
if (aecm->initFlag != kInitCheck) {
return AECM_UNINITIALIZED_ERROR;
}
if (nrOfSamples != 80 && nrOfSamples != 160) {
return AECM_BAD_PARAMETER_ERROR;
}
if (msInSndCardBuf < 0) {
msInSndCardBuf = 0;
retVal = AECM_BAD_PARAMETER_WARNING;
} else if (msInSndCardBuf > 500) {
msInSndCardBuf = 500;
retVal = AECM_BAD_PARAMETER_WARNING;
}
msInSndCardBuf += 10;
aecm->msInSndCardBuf = msInSndCardBuf;
nFrames = nrOfSamples / FRAME_LEN;
nBlocks10ms = nFrames / aecm->aecmCore->mult;
if (aecm->ECstartup) {
if (nearendClean == NULL) {
if (out != nearendNoisy) {
memcpy(out, nearendNoisy, sizeof(short) * nrOfSamples);
}
} else if (out != nearendClean) {
memcpy(out, nearendClean, sizeof(short) * nrOfSamples);
}
nmbrOfFilledBuffers =
(short)WebRtc_available_read(aecm->farendBuf) / FRAME_LEN;
// The AECM is in the start up mode
// AECM is disabled until the soundcard buffer and farend buffers are OK
// Mechanism to ensure that the soundcard buffer is reasonably stable.
if (aecm->checkBuffSize) {
aecm->checkBufSizeCtr++;
// Before we fill up the far end buffer we require the amount of data on
// the sound card to be stable (+/-8 ms) compared to the first value. This
// comparison is made during the following 4 consecutive frames. If it
// seems to be stable then we start to fill up the far end buffer.
if (aecm->counter == 0) {
aecm->firstVal = aecm->msInSndCardBuf;
aecm->sum = 0;
}
if (abs(aecm->firstVal - aecm->msInSndCardBuf) <
WEBRTC_SPL_MAX(0.2 * aecm->msInSndCardBuf, kSampMsNb)) {
aecm->sum += aecm->msInSndCardBuf;
aecm->counter++;
} else {
aecm->counter = 0;
}
if (aecm->counter * nBlocks10ms >= 6) {
// The farend buffer size is determined in blocks of 80 samples
// Use 75% of the average value of the soundcard buffer
aecm->bufSizeStart = WEBRTC_SPL_MIN(
(3 * aecm->sum * aecm->aecmCore->mult) / (aecm->counter * 40),
BUF_SIZE_FRAMES);
// buffersize has now been determined
aecm->checkBuffSize = 0;
}
if (aecm->checkBufSizeCtr * nBlocks10ms > 50) {
// for really bad sound cards, don't disable echocanceller for more than
// 0.5 sec
aecm->bufSizeStart = WEBRTC_SPL_MIN(
(3 * aecm->msInSndCardBuf * aecm->aecmCore->mult) / 40,
BUF_SIZE_FRAMES);
aecm->checkBuffSize = 0;
}
}
// if checkBuffSize changed in the if-statement above
if (!aecm->checkBuffSize) {
// soundcard buffer is now reasonably stable
// When the far end buffer is filled with approximately the same amount of
// data as the amount on the sound card we end the start up phase and
// start to cancel echoes.
if (nmbrOfFilledBuffers == aecm->bufSizeStart) {
aecm->ECstartup = 0; // Enable the AECM
} else if (nmbrOfFilledBuffers > aecm->bufSizeStart) {
WebRtc_MoveReadPtr(aecm->farendBuf,
(int)WebRtc_available_read(aecm->farendBuf) -
(int)aecm->bufSizeStart * FRAME_LEN);
aecm->ECstartup = 0;
}
}
} else {
// AECM is enabled
// Note only 1 block supported for nb and 2 blocks for wb
for (i = 0; i < nFrames; i++) {
int16_t farend[FRAME_LEN];
const int16_t* farend_ptr = NULL;
nmbrOfFilledBuffers =
(short)WebRtc_available_read(aecm->farendBuf) / FRAME_LEN;
// Check that there is data in the far end buffer
if (nmbrOfFilledBuffers > 0) {
// Get the next 80 samples from the farend buffer
WebRtc_ReadBuffer(aecm->farendBuf, (void**)&farend_ptr, farend,
FRAME_LEN);
// Always store the last frame for use when we run out of data
memcpy(&(aecm->farendOld[i][0]), farend_ptr, FRAME_LEN * sizeof(short));
} else {
// We have no data so we use the last played frame
memcpy(farend, &(aecm->farendOld[i][0]), FRAME_LEN * sizeof(short));
farend_ptr = farend;
}
// Call buffer delay estimator when all data is extracted,
// i,e. i = 0 for NB and i = 1 for WB
if ((i == 0 && aecm->sampFreq == 8000) ||
(i == 1 && aecm->sampFreq == 16000)) {
WebRtcAecm_EstBufDelay(aecm, aecm->msInSndCardBuf);
}
// Call the AECM
/*WebRtcAecm_ProcessFrame(aecm->aecmCore, farend, &nearend[FRAME_LEN * i],
&out[FRAME_LEN * i], aecm->knownDelay);*/
if (WebRtcAecm_ProcessFrame(
aecm->aecmCore, farend_ptr, &nearendNoisy[FRAME_LEN * i],
(nearendClean ? &nearendClean[FRAME_LEN * i] : NULL),
&out[FRAME_LEN * i]) == -1)
return -1;
}
}
#ifdef AEC_DEBUG
msInAECBuf = (short)WebRtc_available_read(aecm->farendBuf) /
(kSampMsNb * aecm->aecmCore->mult);
fwrite(&msInAECBuf, 2, 1, aecm->bufFile);
fwrite(&(aecm->knownDelay), sizeof(aecm->knownDelay), 1, aecm->delayFile);
#endif
return retVal;
}
int32_t WebRtcAecm_set_config(void* aecmInst, AecmConfig config) {
AecMobile* aecm = static_cast<AecMobile*>(aecmInst);
if (aecm == NULL) {
return -1;
}
if (aecm->initFlag != kInitCheck) {
return AECM_UNINITIALIZED_ERROR;
}
if (config.cngMode != AecmFalse && config.cngMode != AecmTrue) {
return AECM_BAD_PARAMETER_ERROR;
}
aecm->aecmCore->cngMode = config.cngMode;
if (config.echoMode < 0 || config.echoMode > 4) {
return AECM_BAD_PARAMETER_ERROR;
}
aecm->echoMode = config.echoMode;
if (aecm->echoMode == 0) {
aecm->aecmCore->supGain = SUPGAIN_DEFAULT >> 3;
aecm->aecmCore->supGainOld = SUPGAIN_DEFAULT >> 3;
aecm->aecmCore->supGainErrParamA = SUPGAIN_ERROR_PARAM_A >> 3;
aecm->aecmCore->supGainErrParamD = SUPGAIN_ERROR_PARAM_D >> 3;
aecm->aecmCore->supGainErrParamDiffAB =
(SUPGAIN_ERROR_PARAM_A >> 3) - (SUPGAIN_ERROR_PARAM_B >> 3);
aecm->aecmCore->supGainErrParamDiffBD =
(SUPGAIN_ERROR_PARAM_B >> 3) - (SUPGAIN_ERROR_PARAM_D >> 3);
} else if (aecm->echoMode == 1) {
aecm->aecmCore->supGain = SUPGAIN_DEFAULT >> 2;
aecm->aecmCore->supGainOld = SUPGAIN_DEFAULT >> 2;
aecm->aecmCore->supGainErrParamA = SUPGAIN_ERROR_PARAM_A >> 2;
aecm->aecmCore->supGainErrParamD = SUPGAIN_ERROR_PARAM_D >> 2;
aecm->aecmCore->supGainErrParamDiffAB =
(SUPGAIN_ERROR_PARAM_A >> 2) - (SUPGAIN_ERROR_PARAM_B >> 2);
aecm->aecmCore->supGainErrParamDiffBD =
(SUPGAIN_ERROR_PARAM_B >> 2) - (SUPGAIN_ERROR_PARAM_D >> 2);
} else if (aecm->echoMode == 2) {
aecm->aecmCore->supGain = SUPGAIN_DEFAULT >> 1;
aecm->aecmCore->supGainOld = SUPGAIN_DEFAULT >> 1;
aecm->aecmCore->supGainErrParamA = SUPGAIN_ERROR_PARAM_A >> 1;
aecm->aecmCore->supGainErrParamD = SUPGAIN_ERROR_PARAM_D >> 1;
aecm->aecmCore->supGainErrParamDiffAB =
(SUPGAIN_ERROR_PARAM_A >> 1) - (SUPGAIN_ERROR_PARAM_B >> 1);
aecm->aecmCore->supGainErrParamDiffBD =
(SUPGAIN_ERROR_PARAM_B >> 1) - (SUPGAIN_ERROR_PARAM_D >> 1);
} else if (aecm->echoMode == 3) {
aecm->aecmCore->supGain = SUPGAIN_DEFAULT;
aecm->aecmCore->supGainOld = SUPGAIN_DEFAULT;
aecm->aecmCore->supGainErrParamA = SUPGAIN_ERROR_PARAM_A;
aecm->aecmCore->supGainErrParamD = SUPGAIN_ERROR_PARAM_D;
aecm->aecmCore->supGainErrParamDiffAB =
SUPGAIN_ERROR_PARAM_A - SUPGAIN_ERROR_PARAM_B;
aecm->aecmCore->supGainErrParamDiffBD =
SUPGAIN_ERROR_PARAM_B - SUPGAIN_ERROR_PARAM_D;
} else if (aecm->echoMode == 4) {
aecm->aecmCore->supGain = SUPGAIN_DEFAULT << 1;
aecm->aecmCore->supGainOld = SUPGAIN_DEFAULT << 1;
aecm->aecmCore->supGainErrParamA = SUPGAIN_ERROR_PARAM_A << 1;
aecm->aecmCore->supGainErrParamD = SUPGAIN_ERROR_PARAM_D << 1;
aecm->aecmCore->supGainErrParamDiffAB =
(SUPGAIN_ERROR_PARAM_A << 1) - (SUPGAIN_ERROR_PARAM_B << 1);
aecm->aecmCore->supGainErrParamDiffBD =
(SUPGAIN_ERROR_PARAM_B << 1) - (SUPGAIN_ERROR_PARAM_D << 1);
}
return 0;
}
int32_t WebRtcAecm_InitEchoPath(void* aecmInst,
const void* echo_path,
size_t size_bytes) {
AecMobile* aecm = static_cast<AecMobile*>(aecmInst);
const int16_t* echo_path_ptr = static_cast<const int16_t*>(echo_path);
if (aecmInst == NULL) {
return -1;
}
if (echo_path == NULL) {
return AECM_NULL_POINTER_ERROR;
}
if (size_bytes != WebRtcAecm_echo_path_size_bytes()) {
// Input channel size does not match the size of AECM
return AECM_BAD_PARAMETER_ERROR;
}
if (aecm->initFlag != kInitCheck) {
return AECM_UNINITIALIZED_ERROR;
}
WebRtcAecm_InitEchoPathCore(aecm->aecmCore, echo_path_ptr);
return 0;
}
int32_t WebRtcAecm_GetEchoPath(void* aecmInst,
void* echo_path,
size_t size_bytes) {
AecMobile* aecm = static_cast<AecMobile*>(aecmInst);
int16_t* echo_path_ptr = static_cast<int16_t*>(echo_path);
if (aecmInst == NULL) {
return -1;
}
if (echo_path == NULL) {
return AECM_NULL_POINTER_ERROR;
}
if (size_bytes != WebRtcAecm_echo_path_size_bytes()) {
// Input channel size does not match the size of AECM
return AECM_BAD_PARAMETER_ERROR;
}
if (aecm->initFlag != kInitCheck) {
return AECM_UNINITIALIZED_ERROR;
}
memcpy(echo_path_ptr, aecm->aecmCore->channelStored, size_bytes);
return 0;
}
size_t WebRtcAecm_echo_path_size_bytes() {
return (PART_LEN1 * sizeof(int16_t));
}
static int WebRtcAecm_EstBufDelay(AecMobile* aecm, short msInSndCardBuf) {
short delayNew, nSampSndCard;
short nSampFar = (short)WebRtc_available_read(aecm->farendBuf);
short diff;
nSampSndCard = msInSndCardBuf * kSampMsNb * aecm->aecmCore->mult;
delayNew = nSampSndCard - nSampFar;
if (delayNew < FRAME_LEN) {
WebRtc_MoveReadPtr(aecm->farendBuf, FRAME_LEN);
delayNew += FRAME_LEN;
}
aecm->filtDelay =
WEBRTC_SPL_MAX(0, (8 * aecm->filtDelay + 2 * delayNew) / 10);
diff = aecm->filtDelay - aecm->knownDelay;
if (diff > 224) {
if (aecm->lastDelayDiff < 96) {
aecm->timeForDelayChange = 0;
} else {
aecm->timeForDelayChange++;
}
} else if (diff < 96 && aecm->knownDelay > 0) {
if (aecm->lastDelayDiff > 224) {
aecm->timeForDelayChange = 0;
} else {
aecm->timeForDelayChange++;
}
} else {
aecm->timeForDelayChange = 0;
}
aecm->lastDelayDiff = diff;
if (aecm->timeForDelayChange > 25) {
aecm->knownDelay = WEBRTC_SPL_MAX((int)aecm->filtDelay - 160, 0);
}
return 0;
}
static int WebRtcAecm_DelayComp(AecMobile* aecm) {
int nSampFar = (int)WebRtc_available_read(aecm->farendBuf);
int nSampSndCard, delayNew, nSampAdd;
const int maxStuffSamp = 10 * FRAME_LEN;
nSampSndCard = aecm->msInSndCardBuf * kSampMsNb * aecm->aecmCore->mult;
delayNew = nSampSndCard - nSampFar;
if (delayNew > FAR_BUF_LEN - FRAME_LEN * aecm->aecmCore->mult) {
// The difference of the buffer sizes is larger than the maximum
// allowed known delay. Compensate by stuffing the buffer.
nSampAdd =
(int)(WEBRTC_SPL_MAX(((nSampSndCard >> 1) - nSampFar), FRAME_LEN));
nSampAdd = WEBRTC_SPL_MIN(nSampAdd, maxStuffSamp);
WebRtc_MoveReadPtr(aecm->farendBuf, -nSampAdd);
aecm->delayChange = 1; // the delay needs to be updated
}
return 0;
}
} // namespace webrtc