diff options
Diffstat (limited to 'src/modules/audio_processing/aecm/echo_control_mobile.c')
| -rw-r--r-- | src/modules/audio_processing/aecm/echo_control_mobile.c | 808 |
1 files changed, 808 insertions, 0 deletions
diff --git a/src/modules/audio_processing/aecm/echo_control_mobile.c b/src/modules/audio_processing/aecm/echo_control_mobile.c new file mode 100644 index 0000000000..49798b74c6 --- /dev/null +++ b/src/modules/audio_processing/aecm/echo_control_mobile.c @@ -0,0 +1,808 @@ +/* + * 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. + */ + +#include <stdlib.h> +//#include <string.h> + +#include "echo_control_mobile.h" +#include "aecm_core.h" +#include "ring_buffer.h" +#ifdef AEC_DEBUG +#include <stdio.h> +#endif +#ifdef MAC_IPHONE_PRINT +#include <time.h> +#include <stdio.h> +#elif defined ARM_WINM_LOG +#include "windows.h" +extern HANDLE logFile; +#endif + +#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; + + WebRtc_Word16 echoMode; + +#ifdef AEC_DEBUG + FILE *bufFile; + FILE *delayFile; + FILE *preCompFile; + FILE *postCompFile; +#endif // AEC_DEBUG + // Structures + void *farendBuf; + + int lastError; + + AecmCore_t *aecmCore; +} aecmob_t; + +// Estimates delay to set the position of the farend buffer read pointer +// (controlled by knownDelay) +static int WebRtcAecm_EstBufDelay(aecmob_t *aecmInst, short msInSndCardBuf); + +// Stuffs the farend buffer if the estimated delay is too large +static int WebRtcAecm_DelayComp(aecmob_t *aecmInst); + +WebRtc_Word32 WebRtcAecm_Create(void **aecmInst) +{ + aecmob_t *aecm; + if (aecmInst == NULL) + { + return -1; + } + + aecm = malloc(sizeof(aecmob_t)); + *aecmInst = aecm; + if (aecm == NULL) + { + return -1; + } + + if (WebRtcAecm_CreateCore(&aecm->aecmCore) == -1) + { + WebRtcAecm_Free(aecm); + aecm = NULL; + return -1; + } + + if (WebRtc_CreateBuffer(&aecm->farendBuf, kBufSizeSamp, + sizeof(int16_t)) == -1) + { + WebRtcAecm_Free(aecm); + aecm = NULL; + return -1; + } + + aecm->initFlag = 0; + aecm->lastError = 0; + +#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 0; +} + +WebRtc_Word32 WebRtcAecm_Free(void *aecmInst) +{ + aecmob_t *aecm = aecmInst; + + if (aecm == NULL) + { + return -1; + } + +#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); + + return 0; +} + +WebRtc_Word32 WebRtcAecm_Init(void *aecmInst, WebRtc_Word32 sampFreq) +{ + aecmob_t *aecm = aecmInst; + AecmConfig aecConfig; + + if (aecm == NULL) + { + return -1; + } + + if (sampFreq != 8000 && sampFreq != 16000) + { + aecm->lastError = AECM_BAD_PARAMETER_ERROR; + return -1; + } + aecm->sampFreq = sampFreq; + + // Initialize AECM core + if (WebRtcAecm_InitCore(aecm->aecmCore, aecm->sampFreq) == -1) + { + aecm->lastError = AECM_UNSPECIFIED_ERROR; + return -1; + } + + // Initialize farend buffer + if (WebRtc_InitBuffer(aecm->farendBuf) == -1) + { + aecm->lastError = AECM_UNSPECIFIED_ERROR; + return -1; + } + + 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][0], 0, 160); + + // Default settings. + aecConfig.cngMode = AecmTrue; + aecConfig.echoMode = 3; + + if (WebRtcAecm_set_config(aecm, aecConfig) == -1) + { + aecm->lastError = AECM_UNSPECIFIED_ERROR; + return -1; + } + + return 0; +} + +WebRtc_Word32 WebRtcAecm_BufferFarend(void *aecmInst, const WebRtc_Word16 *farend, + WebRtc_Word16 nrOfSamples) +{ + aecmob_t *aecm = aecmInst; + WebRtc_Word32 retVal = 0; + + if (aecm == NULL) + { + return -1; + } + + if (farend == NULL) + { + aecm->lastError = AECM_NULL_POINTER_ERROR; + return -1; + } + + if (aecm->initFlag != kInitCheck) + { + aecm->lastError = AECM_UNINITIALIZED_ERROR; + return -1; + } + + if (nrOfSamples != 80 && nrOfSamples != 160) + { + aecm->lastError = AECM_BAD_PARAMETER_ERROR; + return -1; + } + + // TODO: Is this really a good idea? + if (!aecm->ECstartup) + { + WebRtcAecm_DelayComp(aecm); + } + + WebRtc_WriteBuffer(aecm->farendBuf, farend, (size_t) nrOfSamples); + + return retVal; +} + +WebRtc_Word32 WebRtcAecm_Process(void *aecmInst, const WebRtc_Word16 *nearendNoisy, + const WebRtc_Word16 *nearendClean, WebRtc_Word16 *out, + WebRtc_Word16 nrOfSamples, WebRtc_Word16 msInSndCardBuf) +{ + aecmob_t *aecm = aecmInst; + WebRtc_Word32 retVal = 0; + short i; + short nmbrOfFilledBuffers; + short nBlocks10ms; + short nFrames; +#ifdef AEC_DEBUG + short msInAECBuf; +#endif + +#ifdef ARM_WINM_LOG + __int64 freq, start, end, diff; + unsigned int milliseconds; + DWORD temp; +#elif defined MAC_IPHONE_PRINT + // double endtime = 0, starttime = 0; + struct timeval starttime; + struct timeval endtime; + static long int timeused = 0; + static int timecount = 0; +#endif + + if (aecm == NULL) + { + return -1; + } + + if (nearendNoisy == NULL) + { + aecm->lastError = AECM_NULL_POINTER_ERROR; + return -1; + } + + if (out == NULL) + { + aecm->lastError = AECM_NULL_POINTER_ERROR; + return -1; + } + + if (aecm->initFlag != kInitCheck) + { + aecm->lastError = AECM_UNINITIALIZED_ERROR; + return -1; + } + + if (nrOfSamples != 80 && nrOfSamples != 160) + { + aecm->lastError = AECM_BAD_PARAMETER_ERROR; + return -1; + } + + if (msInSndCardBuf < 0) + { + msInSndCardBuf = 0; + aecm->lastError = AECM_BAD_PARAMETER_WARNING; + retVal = -1; + } else if (msInSndCardBuf > 500) + { + msInSndCardBuf = 500; + aecm->lastError = AECM_BAD_PARAMETER_WARNING; + retVal = -1; + } + msInSndCardBuf += 10; + aecm->msInSndCardBuf = msInSndCardBuf; + + nFrames = nrOfSamples / FRAME_LEN; + nBlocks10ms = nFrames / aecm->aecmCore->mult; + + if (aecm->ECstartup) + { + if (nearendClean == NULL) + { + memcpy(out, nearendNoisy, sizeof(short) * nrOfSamples); + } else + { + 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); + } + +#ifdef ARM_WINM_LOG + // measure tick start + QueryPerformanceFrequency((LARGE_INTEGER*)&freq); + QueryPerformanceCounter((LARGE_INTEGER*)&start); +#elif defined MAC_IPHONE_PRINT + // starttime = clock()/(double)CLOCKS_PER_SEC; + gettimeofday(&starttime, NULL); +#endif + // Call the AECM + /*WebRtcAecm_ProcessFrame(aecm->aecmCore, farend, &nearend[FRAME_LEN * i], + &out[FRAME_LEN * i], aecm->knownDelay);*/ + if (nearendClean == NULL) + { + if (WebRtcAecm_ProcessFrame(aecm->aecmCore, + farend_ptr, + &nearendNoisy[FRAME_LEN * i], + NULL, + &out[FRAME_LEN * i]) == -1) + { + return -1; + } + } else + { + if (WebRtcAecm_ProcessFrame(aecm->aecmCore, + farend_ptr, + &nearendNoisy[FRAME_LEN * i], + &nearendClean[FRAME_LEN * i], + &out[FRAME_LEN * i]) == -1) + { + return -1; + } + } + +#ifdef ARM_WINM_LOG + + // measure tick end + QueryPerformanceCounter((LARGE_INTEGER*)&end); + + if(end > start) + { + diff = ((end - start) * 1000) / (freq/1000); + milliseconds = (unsigned int)(diff & 0xffffffff); + WriteFile (logFile, &milliseconds, sizeof(unsigned int), &temp, NULL); + } +#elif defined MAC_IPHONE_PRINT + // endtime = clock()/(double)CLOCKS_PER_SEC; + // printf("%f\n", endtime - starttime); + + gettimeofday(&endtime, NULL); + + if( endtime.tv_usec > starttime.tv_usec) + { + timeused += endtime.tv_usec - starttime.tv_usec; + } else + { + timeused += endtime.tv_usec + 1000000 - starttime.tv_usec; + } + + if(++timecount == 1000) + { + timecount = 0; + printf("AEC: %ld\n", timeused); + timeused = 0; + } +#endif + + } + } + +#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; +} + +WebRtc_Word32 WebRtcAecm_set_config(void *aecmInst, AecmConfig config) +{ + aecmob_t *aecm = aecmInst; + + if (aecm == NULL) + { + return -1; + } + + if (aecm->initFlag != kInitCheck) + { + aecm->lastError = AECM_UNINITIALIZED_ERROR; + return -1; + } + + if (config.cngMode != AecmFalse && config.cngMode != AecmTrue) + { + aecm->lastError = AECM_BAD_PARAMETER_ERROR; + return -1; + } + aecm->aecmCore->cngMode = config.cngMode; + + if (config.echoMode < 0 || config.echoMode > 4) + { + aecm->lastError = AECM_BAD_PARAMETER_ERROR; + return -1; + } + 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; +} + +WebRtc_Word32 WebRtcAecm_get_config(void *aecmInst, AecmConfig *config) +{ + aecmob_t *aecm = aecmInst; + + if (aecm == NULL) + { + return -1; + } + + if (config == NULL) + { + aecm->lastError = AECM_NULL_POINTER_ERROR; + return -1; + } + + if (aecm->initFlag != kInitCheck) + { + aecm->lastError = AECM_UNINITIALIZED_ERROR; + return -1; + } + + config->cngMode = aecm->aecmCore->cngMode; + config->echoMode = aecm->echoMode; + + return 0; +} + +WebRtc_Word32 WebRtcAecm_InitEchoPath(void* aecmInst, + const void* echo_path, + size_t size_bytes) +{ + aecmob_t *aecm = aecmInst; + const WebRtc_Word16* echo_path_ptr = echo_path; + + if ((aecm == NULL) || (echo_path == NULL)) + { + aecm->lastError = AECM_NULL_POINTER_ERROR; + return -1; + } + if (size_bytes != WebRtcAecm_echo_path_size_bytes()) + { + // Input channel size does not match the size of AECM + aecm->lastError = AECM_BAD_PARAMETER_ERROR; + return -1; + } + if (aecm->initFlag != kInitCheck) + { + aecm->lastError = AECM_UNINITIALIZED_ERROR; + return -1; + } + + WebRtcAecm_InitEchoPathCore(aecm->aecmCore, echo_path_ptr); + + return 0; +} + +WebRtc_Word32 WebRtcAecm_GetEchoPath(void* aecmInst, + void* echo_path, + size_t size_bytes) +{ + aecmob_t *aecm = aecmInst; + WebRtc_Word16* echo_path_ptr = echo_path; + + if ((aecm == NULL) || (echo_path == NULL)) + { + aecm->lastError = AECM_NULL_POINTER_ERROR; + return -1; + } + if (size_bytes != WebRtcAecm_echo_path_size_bytes()) + { + // Input channel size does not match the size of AECM + aecm->lastError = AECM_BAD_PARAMETER_ERROR; + return -1; + } + if (aecm->initFlag != kInitCheck) + { + aecm->lastError = AECM_UNINITIALIZED_ERROR; + return -1; + } + + memcpy(echo_path_ptr, aecm->aecmCore->channelStored, size_bytes); + return 0; +} + +size_t WebRtcAecm_echo_path_size_bytes() +{ + return (PART_LEN1 * sizeof(WebRtc_Word16)); +} + +WebRtc_Word32 WebRtcAecm_get_version(WebRtc_Word8 *versionStr, WebRtc_Word16 len) +{ + const char version[] = "AECM 1.2.0"; + const short versionLen = (short)strlen(version) + 1; // +1 for null-termination + + if (versionStr == NULL) + { + return -1; + } + + if (versionLen > len) + { + return -1; + } + + strncpy(versionStr, version, versionLen); + return 0; +} + +WebRtc_Word32 WebRtcAecm_get_error_code(void *aecmInst) +{ + aecmob_t *aecm = aecmInst; + + if (aecm == NULL) + { + return -1; + } + + return aecm->lastError; +} + +static int WebRtcAecm_EstBufDelay(aecmob_t *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(aecmob_t *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; +} |