diff options
Diffstat (limited to 'third_party/webrtc/src/webrtc/modules/audio_processing/aecm/aecm_core.c')
| -rw-r--r-- | third_party/webrtc/src/webrtc/modules/audio_processing/aecm/aecm_core.c | 1233 |
1 files changed, 1233 insertions, 0 deletions
diff --git a/third_party/webrtc/src/webrtc/modules/audio_processing/aecm/aecm_core.c b/third_party/webrtc/src/webrtc/modules/audio_processing/aecm/aecm_core.c new file mode 100644 index 00000000..b801f07a --- /dev/null +++ b/third_party/webrtc/src/webrtc/modules/audio_processing/aecm/aecm_core.c @@ -0,0 +1,1233 @@ +/* + * 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 "webrtc/modules/audio_processing/aecm/aecm_core.h" + +#include <assert.h> +#include <stddef.h> +#include <stdlib.h> + +#include "webrtc/common_audio/ring_buffer.h" +#include "webrtc/common_audio/signal_processing/include/real_fft.h" +#include "webrtc/modules/audio_processing/aecm/include/echo_control_mobile.h" +#include "webrtc/modules/audio_processing/utility/delay_estimator_wrapper.h" +#include "webrtc/system_wrappers/interface/compile_assert_c.h" +#include "webrtc/system_wrappers/interface/cpu_features_wrapper.h" +#include "webrtc/typedefs.h" + +#ifdef AEC_DEBUG +FILE *dfile; +FILE *testfile; +#endif + +const int16_t WebRtcAecm_kCosTable[] = { + 8192, 8190, 8187, 8180, 8172, 8160, 8147, 8130, 8112, + 8091, 8067, 8041, 8012, 7982, 7948, 7912, 7874, 7834, + 7791, 7745, 7697, 7647, 7595, 7540, 7483, 7424, 7362, + 7299, 7233, 7164, 7094, 7021, 6947, 6870, 6791, 6710, + 6627, 6542, 6455, 6366, 6275, 6182, 6087, 5991, 5892, + 5792, 5690, 5586, 5481, 5374, 5265, 5155, 5043, 4930, + 4815, 4698, 4580, 4461, 4341, 4219, 4096, 3971, 3845, + 3719, 3591, 3462, 3331, 3200, 3068, 2935, 2801, 2667, + 2531, 2395, 2258, 2120, 1981, 1842, 1703, 1563, 1422, + 1281, 1140, 998, 856, 713, 571, 428, 285, 142, + 0, -142, -285, -428, -571, -713, -856, -998, -1140, + -1281, -1422, -1563, -1703, -1842, -1981, -2120, -2258, -2395, + -2531, -2667, -2801, -2935, -3068, -3200, -3331, -3462, -3591, + -3719, -3845, -3971, -4095, -4219, -4341, -4461, -4580, -4698, + -4815, -4930, -5043, -5155, -5265, -5374, -5481, -5586, -5690, + -5792, -5892, -5991, -6087, -6182, -6275, -6366, -6455, -6542, + -6627, -6710, -6791, -6870, -6947, -7021, -7094, -7164, -7233, + -7299, -7362, -7424, -7483, -7540, -7595, -7647, -7697, -7745, + -7791, -7834, -7874, -7912, -7948, -7982, -8012, -8041, -8067, + -8091, -8112, -8130, -8147, -8160, -8172, -8180, -8187, -8190, + -8191, -8190, -8187, -8180, -8172, -8160, -8147, -8130, -8112, + -8091, -8067, -8041, -8012, -7982, -7948, -7912, -7874, -7834, + -7791, -7745, -7697, -7647, -7595, -7540, -7483, -7424, -7362, + -7299, -7233, -7164, -7094, -7021, -6947, -6870, -6791, -6710, + -6627, -6542, -6455, -6366, -6275, -6182, -6087, -5991, -5892, + -5792, -5690, -5586, -5481, -5374, -5265, -5155, -5043, -4930, + -4815, -4698, -4580, -4461, -4341, -4219, -4096, -3971, -3845, + -3719, -3591, -3462, -3331, -3200, -3068, -2935, -2801, -2667, + -2531, -2395, -2258, -2120, -1981, -1842, -1703, -1563, -1422, + -1281, -1140, -998, -856, -713, -571, -428, -285, -142, + 0, 142, 285, 428, 571, 713, 856, 998, 1140, + 1281, 1422, 1563, 1703, 1842, 1981, 2120, 2258, 2395, + 2531, 2667, 2801, 2935, 3068, 3200, 3331, 3462, 3591, + 3719, 3845, 3971, 4095, 4219, 4341, 4461, 4580, 4698, + 4815, 4930, 5043, 5155, 5265, 5374, 5481, 5586, 5690, + 5792, 5892, 5991, 6087, 6182, 6275, 6366, 6455, 6542, + 6627, 6710, 6791, 6870, 6947, 7021, 7094, 7164, 7233, + 7299, 7362, 7424, 7483, 7540, 7595, 7647, 7697, 7745, + 7791, 7834, 7874, 7912, 7948, 7982, 8012, 8041, 8067, + 8091, 8112, 8130, 8147, 8160, 8172, 8180, 8187, 8190 +}; + +const int16_t WebRtcAecm_kSinTable[] = { + 0, 142, 285, 428, 571, 713, 856, 998, + 1140, 1281, 1422, 1563, 1703, 1842, 1981, 2120, + 2258, 2395, 2531, 2667, 2801, 2935, 3068, 3200, + 3331, 3462, 3591, 3719, 3845, 3971, 4095, 4219, + 4341, 4461, 4580, 4698, 4815, 4930, 5043, 5155, + 5265, 5374, 5481, 5586, 5690, 5792, 5892, 5991, + 6087, 6182, 6275, 6366, 6455, 6542, 6627, 6710, + 6791, 6870, 6947, 7021, 7094, 7164, 7233, 7299, + 7362, 7424, 7483, 7540, 7595, 7647, 7697, 7745, + 7791, 7834, 7874, 7912, 7948, 7982, 8012, 8041, + 8067, 8091, 8112, 8130, 8147, 8160, 8172, 8180, + 8187, 8190, 8191, 8190, 8187, 8180, 8172, 8160, + 8147, 8130, 8112, 8091, 8067, 8041, 8012, 7982, + 7948, 7912, 7874, 7834, 7791, 7745, 7697, 7647, + 7595, 7540, 7483, 7424, 7362, 7299, 7233, 7164, + 7094, 7021, 6947, 6870, 6791, 6710, 6627, 6542, + 6455, 6366, 6275, 6182, 6087, 5991, 5892, 5792, + 5690, 5586, 5481, 5374, 5265, 5155, 5043, 4930, + 4815, 4698, 4580, 4461, 4341, 4219, 4096, 3971, + 3845, 3719, 3591, 3462, 3331, 3200, 3068, 2935, + 2801, 2667, 2531, 2395, 2258, 2120, 1981, 1842, + 1703, 1563, 1422, 1281, 1140, 998, 856, 713, + 571, 428, 285, 142, 0, -142, -285, -428, + -571, -713, -856, -998, -1140, -1281, -1422, -1563, + -1703, -1842, -1981, -2120, -2258, -2395, -2531, -2667, + -2801, -2935, -3068, -3200, -3331, -3462, -3591, -3719, + -3845, -3971, -4095, -4219, -4341, -4461, -4580, -4698, + -4815, -4930, -5043, -5155, -5265, -5374, -5481, -5586, + -5690, -5792, -5892, -5991, -6087, -6182, -6275, -6366, + -6455, -6542, -6627, -6710, -6791, -6870, -6947, -7021, + -7094, -7164, -7233, -7299, -7362, -7424, -7483, -7540, + -7595, -7647, -7697, -7745, -7791, -7834, -7874, -7912, + -7948, -7982, -8012, -8041, -8067, -8091, -8112, -8130, + -8147, -8160, -8172, -8180, -8187, -8190, -8191, -8190, + -8187, -8180, -8172, -8160, -8147, -8130, -8112, -8091, + -8067, -8041, -8012, -7982, -7948, -7912, -7874, -7834, + -7791, -7745, -7697, -7647, -7595, -7540, -7483, -7424, + -7362, -7299, -7233, -7164, -7094, -7021, -6947, -6870, + -6791, -6710, -6627, -6542, -6455, -6366, -6275, -6182, + -6087, -5991, -5892, -5792, -5690, -5586, -5481, -5374, + -5265, -5155, -5043, -4930, -4815, -4698, -4580, -4461, + -4341, -4219, -4096, -3971, -3845, -3719, -3591, -3462, + -3331, -3200, -3068, -2935, -2801, -2667, -2531, -2395, + -2258, -2120, -1981, -1842, -1703, -1563, -1422, -1281, + -1140, -998, -856, -713, -571, -428, -285, -142 +}; + +// Initialization table for echo channel in 8 kHz +static const int16_t kChannelStored8kHz[PART_LEN1] = { + 2040, 1815, 1590, 1498, 1405, 1395, 1385, 1418, + 1451, 1506, 1562, 1644, 1726, 1804, 1882, 1918, + 1953, 1982, 2010, 2025, 2040, 2034, 2027, 2021, + 2014, 1997, 1980, 1925, 1869, 1800, 1732, 1683, + 1635, 1604, 1572, 1545, 1517, 1481, 1444, 1405, + 1367, 1331, 1294, 1270, 1245, 1239, 1233, 1247, + 1260, 1282, 1303, 1338, 1373, 1407, 1441, 1470, + 1499, 1524, 1549, 1565, 1582, 1601, 1621, 1649, + 1676 +}; + +// Initialization table for echo channel in 16 kHz +static const int16_t kChannelStored16kHz[PART_LEN1] = { + 2040, 1590, 1405, 1385, 1451, 1562, 1726, 1882, + 1953, 2010, 2040, 2027, 2014, 1980, 1869, 1732, + 1635, 1572, 1517, 1444, 1367, 1294, 1245, 1233, + 1260, 1303, 1373, 1441, 1499, 1549, 1582, 1621, + 1676, 1741, 1802, 1861, 1921, 1983, 2040, 2102, + 2170, 2265, 2375, 2515, 2651, 2781, 2922, 3075, + 3253, 3471, 3738, 3976, 4151, 4258, 4308, 4288, + 4270, 4253, 4237, 4179, 4086, 3947, 3757, 3484, + 3153 +}; + +// Moves the pointer to the next entry and inserts |far_spectrum| and +// corresponding Q-domain in its buffer. +// +// Inputs: +// - self : Pointer to the delay estimation instance +// - far_spectrum : Pointer to the far end spectrum +// - far_q : Q-domain of far end spectrum +// +void WebRtcAecm_UpdateFarHistory(AecmCore* self, + uint16_t* far_spectrum, + int far_q) { + // Get new buffer position + self->far_history_pos++; + if (self->far_history_pos >= MAX_DELAY) { + self->far_history_pos = 0; + } + // Update Q-domain buffer + self->far_q_domains[self->far_history_pos] = far_q; + // Update far end spectrum buffer + memcpy(&(self->far_history[self->far_history_pos * PART_LEN1]), + far_spectrum, + sizeof(uint16_t) * PART_LEN1); +} + +// Returns a pointer to the far end spectrum aligned to current near end +// spectrum. The function WebRtc_DelayEstimatorProcessFix(...) should have been +// called before AlignedFarend(...). Otherwise, you get the pointer to the +// previous frame. The memory is only valid until the next call of +// WebRtc_DelayEstimatorProcessFix(...). +// +// Inputs: +// - self : Pointer to the AECM instance. +// - delay : Current delay estimate. +// +// Output: +// - far_q : The Q-domain of the aligned far end spectrum +// +// Return value: +// - far_spectrum : Pointer to the aligned far end spectrum +// NULL - Error +// +const uint16_t* WebRtcAecm_AlignedFarend(AecmCore* self, + int* far_q, + int delay) { + int buffer_position = 0; + assert(self != NULL); + buffer_position = self->far_history_pos - delay; + + // Check buffer position + if (buffer_position < 0) { + buffer_position += MAX_DELAY; + } + // Get Q-domain + *far_q = self->far_q_domains[buffer_position]; + // Return far end spectrum + return &(self->far_history[buffer_position * PART_LEN1]); +} + +// Declare function pointers. +CalcLinearEnergies WebRtcAecm_CalcLinearEnergies; +StoreAdaptiveChannel WebRtcAecm_StoreAdaptiveChannel; +ResetAdaptiveChannel WebRtcAecm_ResetAdaptiveChannel; + +AecmCore* WebRtcAecm_CreateCore() { + AecmCore* aecm = malloc(sizeof(AecmCore)); + + aecm->farFrameBuf = WebRtc_CreateBuffer(FRAME_LEN + PART_LEN, + sizeof(int16_t)); + if (!aecm->farFrameBuf) + { + WebRtcAecm_FreeCore(aecm); + return NULL; + } + + aecm->nearNoisyFrameBuf = WebRtc_CreateBuffer(FRAME_LEN + PART_LEN, + sizeof(int16_t)); + if (!aecm->nearNoisyFrameBuf) + { + WebRtcAecm_FreeCore(aecm); + return NULL; + } + + aecm->nearCleanFrameBuf = WebRtc_CreateBuffer(FRAME_LEN + PART_LEN, + sizeof(int16_t)); + if (!aecm->nearCleanFrameBuf) + { + WebRtcAecm_FreeCore(aecm); + return NULL; + } + + aecm->outFrameBuf = WebRtc_CreateBuffer(FRAME_LEN + PART_LEN, + sizeof(int16_t)); + if (!aecm->outFrameBuf) + { + WebRtcAecm_FreeCore(aecm); + return NULL; + } + + aecm->delay_estimator_farend = WebRtc_CreateDelayEstimatorFarend(PART_LEN1, + MAX_DELAY); + if (aecm->delay_estimator_farend == NULL) { + WebRtcAecm_FreeCore(aecm); + return NULL; + } + aecm->delay_estimator = + WebRtc_CreateDelayEstimator(aecm->delay_estimator_farend, 0); + if (aecm->delay_estimator == NULL) { + WebRtcAecm_FreeCore(aecm); + return NULL; + } + // TODO(bjornv): Explicitly disable robust delay validation until no + // performance regression has been established. Then remove the line. + WebRtc_enable_robust_validation(aecm->delay_estimator, 0); + + aecm->real_fft = WebRtcSpl_CreateRealFFT(PART_LEN_SHIFT); + if (aecm->real_fft == NULL) { + WebRtcAecm_FreeCore(aecm); + return NULL; + } + + // Init some aecm pointers. 16 and 32 byte alignment is only necessary + // for Neon code currently. + aecm->xBuf = (int16_t*) (((uintptr_t)aecm->xBuf_buf + 31) & ~ 31); + aecm->dBufClean = (int16_t*) (((uintptr_t)aecm->dBufClean_buf + 31) & ~ 31); + aecm->dBufNoisy = (int16_t*) (((uintptr_t)aecm->dBufNoisy_buf + 31) & ~ 31); + aecm->outBuf = (int16_t*) (((uintptr_t)aecm->outBuf_buf + 15) & ~ 15); + aecm->channelStored = (int16_t*) (((uintptr_t) + aecm->channelStored_buf + 15) & ~ 15); + aecm->channelAdapt16 = (int16_t*) (((uintptr_t) + aecm->channelAdapt16_buf + 15) & ~ 15); + aecm->channelAdapt32 = (int32_t*) (((uintptr_t) + aecm->channelAdapt32_buf + 31) & ~ 31); + + return aecm; +} + +void WebRtcAecm_InitEchoPathCore(AecmCore* aecm, const int16_t* echo_path) { + int i = 0; + + // Reset the stored channel + memcpy(aecm->channelStored, echo_path, sizeof(int16_t) * PART_LEN1); + // Reset the adapted channels + memcpy(aecm->channelAdapt16, echo_path, sizeof(int16_t) * PART_LEN1); + for (i = 0; i < PART_LEN1; i++) + { + aecm->channelAdapt32[i] = (int32_t)aecm->channelAdapt16[i] << 16; + } + + // Reset channel storing variables + aecm->mseAdaptOld = 1000; + aecm->mseStoredOld = 1000; + aecm->mseThreshold = WEBRTC_SPL_WORD32_MAX; + aecm->mseChannelCount = 0; +} + +static void CalcLinearEnergiesC(AecmCore* aecm, + const uint16_t* far_spectrum, + int32_t* echo_est, + uint32_t* far_energy, + uint32_t* echo_energy_adapt, + uint32_t* echo_energy_stored) { + int i; + + // Get energy for the delayed far end signal and estimated + // echo using both stored and adapted channels. + for (i = 0; i < PART_LEN1; i++) + { + echo_est[i] = WEBRTC_SPL_MUL_16_U16(aecm->channelStored[i], + far_spectrum[i]); + (*far_energy) += (uint32_t)(far_spectrum[i]); + *echo_energy_adapt += aecm->channelAdapt16[i] * far_spectrum[i]; + (*echo_energy_stored) += (uint32_t)echo_est[i]; + } +} + +static void StoreAdaptiveChannelC(AecmCore* aecm, + const uint16_t* far_spectrum, + int32_t* echo_est) { + int i; + + // During startup we store the channel every block. + memcpy(aecm->channelStored, aecm->channelAdapt16, sizeof(int16_t) * PART_LEN1); + // Recalculate echo estimate + for (i = 0; i < PART_LEN; i += 4) + { + echo_est[i] = WEBRTC_SPL_MUL_16_U16(aecm->channelStored[i], + far_spectrum[i]); + echo_est[i + 1] = WEBRTC_SPL_MUL_16_U16(aecm->channelStored[i + 1], + far_spectrum[i + 1]); + echo_est[i + 2] = WEBRTC_SPL_MUL_16_U16(aecm->channelStored[i + 2], + far_spectrum[i + 2]); + echo_est[i + 3] = WEBRTC_SPL_MUL_16_U16(aecm->channelStored[i + 3], + far_spectrum[i + 3]); + } + echo_est[i] = WEBRTC_SPL_MUL_16_U16(aecm->channelStored[i], + far_spectrum[i]); +} + +static void ResetAdaptiveChannelC(AecmCore* aecm) { + int i; + + // The stored channel has a significantly lower MSE than the adaptive one for + // two consecutive calculations. Reset the adaptive channel. + memcpy(aecm->channelAdapt16, aecm->channelStored, + sizeof(int16_t) * PART_LEN1); + // Restore the W32 channel + for (i = 0; i < PART_LEN; i += 4) + { + aecm->channelAdapt32[i] = (int32_t)aecm->channelStored[i] << 16; + aecm->channelAdapt32[i + 1] = (int32_t)aecm->channelStored[i + 1] << 16; + aecm->channelAdapt32[i + 2] = (int32_t)aecm->channelStored[i + 2] << 16; + aecm->channelAdapt32[i + 3] = (int32_t)aecm->channelStored[i + 3] << 16; + } + aecm->channelAdapt32[i] = (int32_t)aecm->channelStored[i] << 16; +} + +// Initialize function pointers for ARM Neon platform. +#if (defined WEBRTC_DETECT_NEON || defined WEBRTC_HAS_NEON) +static void WebRtcAecm_InitNeon(void) +{ + WebRtcAecm_StoreAdaptiveChannel = WebRtcAecm_StoreAdaptiveChannelNeon; + WebRtcAecm_ResetAdaptiveChannel = WebRtcAecm_ResetAdaptiveChannelNeon; + WebRtcAecm_CalcLinearEnergies = WebRtcAecm_CalcLinearEnergiesNeon; +} +#endif + +// Initialize function pointers for MIPS platform. +#if defined(MIPS32_LE) +static void WebRtcAecm_InitMips(void) +{ +#if defined(MIPS_DSP_R1_LE) + WebRtcAecm_StoreAdaptiveChannel = WebRtcAecm_StoreAdaptiveChannel_mips; + WebRtcAecm_ResetAdaptiveChannel = WebRtcAecm_ResetAdaptiveChannel_mips; +#endif + WebRtcAecm_CalcLinearEnergies = WebRtcAecm_CalcLinearEnergies_mips; +} +#endif + +// WebRtcAecm_InitCore(...) +// +// This function initializes the AECM instant created with WebRtcAecm_CreateCore(...) +// Input: +// - aecm : Pointer to the Echo Suppression instance +// - samplingFreq : Sampling Frequency +// +// Output: +// - aecm : Initialized instance +// +// Return value : 0 - Ok +// -1 - Error +// +int WebRtcAecm_InitCore(AecmCore* const aecm, int samplingFreq) { + int i = 0; + int32_t tmp32 = PART_LEN1 * PART_LEN1; + int16_t tmp16 = PART_LEN1; + + if (samplingFreq != 8000 && samplingFreq != 16000) + { + samplingFreq = 8000; + return -1; + } + // sanity check of sampling frequency + aecm->mult = (int16_t)samplingFreq / 8000; + + aecm->farBufWritePos = 0; + aecm->farBufReadPos = 0; + aecm->knownDelay = 0; + aecm->lastKnownDelay = 0; + + WebRtc_InitBuffer(aecm->farFrameBuf); + WebRtc_InitBuffer(aecm->nearNoisyFrameBuf); + WebRtc_InitBuffer(aecm->nearCleanFrameBuf); + WebRtc_InitBuffer(aecm->outFrameBuf); + + memset(aecm->xBuf_buf, 0, sizeof(aecm->xBuf_buf)); + memset(aecm->dBufClean_buf, 0, sizeof(aecm->dBufClean_buf)); + memset(aecm->dBufNoisy_buf, 0, sizeof(aecm->dBufNoisy_buf)); + memset(aecm->outBuf_buf, 0, sizeof(aecm->outBuf_buf)); + + aecm->seed = 666; + aecm->totCount = 0; + + if (WebRtc_InitDelayEstimatorFarend(aecm->delay_estimator_farend) != 0) { + return -1; + } + if (WebRtc_InitDelayEstimator(aecm->delay_estimator) != 0) { + return -1; + } + // Set far end histories to zero + memset(aecm->far_history, 0, sizeof(uint16_t) * PART_LEN1 * MAX_DELAY); + memset(aecm->far_q_domains, 0, sizeof(int) * MAX_DELAY); + aecm->far_history_pos = MAX_DELAY; + + aecm->nlpFlag = 1; + aecm->fixedDelay = -1; + + aecm->dfaCleanQDomain = 0; + aecm->dfaCleanQDomainOld = 0; + aecm->dfaNoisyQDomain = 0; + aecm->dfaNoisyQDomainOld = 0; + + memset(aecm->nearLogEnergy, 0, sizeof(aecm->nearLogEnergy)); + aecm->farLogEnergy = 0; + memset(aecm->echoAdaptLogEnergy, 0, sizeof(aecm->echoAdaptLogEnergy)); + memset(aecm->echoStoredLogEnergy, 0, sizeof(aecm->echoStoredLogEnergy)); + + // Initialize the echo channels with a stored shape. + if (samplingFreq == 8000) + { + WebRtcAecm_InitEchoPathCore(aecm, kChannelStored8kHz); + } + else + { + WebRtcAecm_InitEchoPathCore(aecm, kChannelStored16kHz); + } + + memset(aecm->echoFilt, 0, sizeof(aecm->echoFilt)); + memset(aecm->nearFilt, 0, sizeof(aecm->nearFilt)); + aecm->noiseEstCtr = 0; + + aecm->cngMode = AecmTrue; + + memset(aecm->noiseEstTooLowCtr, 0, sizeof(aecm->noiseEstTooLowCtr)); + memset(aecm->noiseEstTooHighCtr, 0, sizeof(aecm->noiseEstTooHighCtr)); + // Shape the initial noise level to an approximate pink noise. + for (i = 0; i < (PART_LEN1 >> 1) - 1; i++) + { + aecm->noiseEst[i] = (tmp32 << 8); + tmp16--; + tmp32 -= (int32_t)((tmp16 << 1) + 1); + } + for (; i < PART_LEN1; i++) + { + aecm->noiseEst[i] = (tmp32 << 8); + } + + aecm->farEnergyMin = WEBRTC_SPL_WORD16_MAX; + aecm->farEnergyMax = WEBRTC_SPL_WORD16_MIN; + aecm->farEnergyMaxMin = 0; + aecm->farEnergyVAD = FAR_ENERGY_MIN; // This prevents false speech detection at the + // beginning. + aecm->farEnergyMSE = 0; + aecm->currentVADValue = 0; + aecm->vadUpdateCount = 0; + aecm->firstVAD = 1; + + aecm->startupState = 0; + aecm->supGain = SUPGAIN_DEFAULT; + aecm->supGainOld = SUPGAIN_DEFAULT; + + aecm->supGainErrParamA = SUPGAIN_ERROR_PARAM_A; + aecm->supGainErrParamD = SUPGAIN_ERROR_PARAM_D; + aecm->supGainErrParamDiffAB = SUPGAIN_ERROR_PARAM_A - SUPGAIN_ERROR_PARAM_B; + aecm->supGainErrParamDiffBD = SUPGAIN_ERROR_PARAM_B - SUPGAIN_ERROR_PARAM_D; + + // Assert a preprocessor definition at compile-time. It's an assumption + // used in assembly code, so check the assembly files before any change. + COMPILE_ASSERT(PART_LEN % 16 == 0); + + // Initialize function pointers. + WebRtcAecm_CalcLinearEnergies = CalcLinearEnergiesC; + WebRtcAecm_StoreAdaptiveChannel = StoreAdaptiveChannelC; + WebRtcAecm_ResetAdaptiveChannel = ResetAdaptiveChannelC; + +#ifdef WEBRTC_DETECT_NEON + uint64_t features = WebRtc_GetCPUFeaturesARM(); + if ((features & kCPUFeatureNEON) != 0) + { + WebRtcAecm_InitNeon(); + } +#elif defined(WEBRTC_HAS_NEON) + WebRtcAecm_InitNeon(); +#endif + +#if defined(MIPS32_LE) + WebRtcAecm_InitMips(); +#endif + return 0; +} + +// TODO(bjornv): This function is currently not used. Add support for these +// parameters from a higher level +int WebRtcAecm_Control(AecmCore* aecm, int delay, int nlpFlag) { + aecm->nlpFlag = nlpFlag; + aecm->fixedDelay = delay; + + return 0; +} + +void WebRtcAecm_FreeCore(AecmCore* aecm) { + if (aecm == NULL) { + return; + } + + WebRtc_FreeBuffer(aecm->farFrameBuf); + WebRtc_FreeBuffer(aecm->nearNoisyFrameBuf); + WebRtc_FreeBuffer(aecm->nearCleanFrameBuf); + WebRtc_FreeBuffer(aecm->outFrameBuf); + + WebRtc_FreeDelayEstimator(aecm->delay_estimator); + WebRtc_FreeDelayEstimatorFarend(aecm->delay_estimator_farend); + WebRtcSpl_FreeRealFFT(aecm->real_fft); + + free(aecm); +} + +int WebRtcAecm_ProcessFrame(AecmCore* aecm, + const int16_t* farend, + const int16_t* nearendNoisy, + const int16_t* nearendClean, + int16_t* out) { + int16_t outBlock_buf[PART_LEN + 8]; // Align buffer to 8-byte boundary. + int16_t* outBlock = (int16_t*) (((uintptr_t) outBlock_buf + 15) & ~ 15); + + int16_t farFrame[FRAME_LEN]; + const int16_t* out_ptr = NULL; + int size = 0; + + // Buffer the current frame. + // Fetch an older one corresponding to the delay. + WebRtcAecm_BufferFarFrame(aecm, farend, FRAME_LEN); + WebRtcAecm_FetchFarFrame(aecm, farFrame, FRAME_LEN, aecm->knownDelay); + + // Buffer the synchronized far and near frames, + // to pass the smaller blocks individually. + WebRtc_WriteBuffer(aecm->farFrameBuf, farFrame, FRAME_LEN); + WebRtc_WriteBuffer(aecm->nearNoisyFrameBuf, nearendNoisy, FRAME_LEN); + if (nearendClean != NULL) + { + WebRtc_WriteBuffer(aecm->nearCleanFrameBuf, nearendClean, FRAME_LEN); + } + + // Process as many blocks as possible. + while (WebRtc_available_read(aecm->farFrameBuf) >= PART_LEN) + { + int16_t far_block[PART_LEN]; + const int16_t* far_block_ptr = NULL; + int16_t near_noisy_block[PART_LEN]; + const int16_t* near_noisy_block_ptr = NULL; + + WebRtc_ReadBuffer(aecm->farFrameBuf, (void**) &far_block_ptr, far_block, + PART_LEN); + WebRtc_ReadBuffer(aecm->nearNoisyFrameBuf, + (void**) &near_noisy_block_ptr, + near_noisy_block, + PART_LEN); + if (nearendClean != NULL) + { + int16_t near_clean_block[PART_LEN]; + const int16_t* near_clean_block_ptr = NULL; + + WebRtc_ReadBuffer(aecm->nearCleanFrameBuf, + (void**) &near_clean_block_ptr, + near_clean_block, + PART_LEN); + if (WebRtcAecm_ProcessBlock(aecm, + far_block_ptr, + near_noisy_block_ptr, + near_clean_block_ptr, + outBlock) == -1) + { + return -1; + } + } else + { + if (WebRtcAecm_ProcessBlock(aecm, + far_block_ptr, + near_noisy_block_ptr, + NULL, + outBlock) == -1) + { + return -1; + } + } + + WebRtc_WriteBuffer(aecm->outFrameBuf, outBlock, PART_LEN); + } + + // Stuff the out buffer if we have less than a frame to output. + // This should only happen for the first frame. + size = (int) WebRtc_available_read(aecm->outFrameBuf); + if (size < FRAME_LEN) + { + WebRtc_MoveReadPtr(aecm->outFrameBuf, size - FRAME_LEN); + } + + // Obtain an output frame. + WebRtc_ReadBuffer(aecm->outFrameBuf, (void**) &out_ptr, out, FRAME_LEN); + if (out_ptr != out) { + // ReadBuffer() hasn't copied to |out| in this case. + memcpy(out, out_ptr, FRAME_LEN * sizeof(int16_t)); + } + + return 0; +} + +// WebRtcAecm_AsymFilt(...) +// +// Performs asymmetric filtering. +// +// Inputs: +// - filtOld : Previous filtered value. +// - inVal : New input value. +// - stepSizePos : Step size when we have a positive contribution. +// - stepSizeNeg : Step size when we have a negative contribution. +// +// Output: +// +// Return: - Filtered value. +// +int16_t WebRtcAecm_AsymFilt(const int16_t filtOld, const int16_t inVal, + const int16_t stepSizePos, + const int16_t stepSizeNeg) +{ + int16_t retVal; + + if ((filtOld == WEBRTC_SPL_WORD16_MAX) | (filtOld == WEBRTC_SPL_WORD16_MIN)) + { + return inVal; + } + retVal = filtOld; + if (filtOld > inVal) + { + retVal -= (filtOld - inVal) >> stepSizeNeg; + } else + { + retVal += (inVal - filtOld) >> stepSizePos; + } + + return retVal; +} + +// ExtractFractionPart(a, zeros) +// +// returns the fraction part of |a|, with |zeros| number of leading zeros, as an +// int16_t scaled to Q8. There is no sanity check of |a| in the sense that the +// number of zeros match. +static int16_t ExtractFractionPart(uint32_t a, int zeros) { + return (int16_t)(((a << zeros) & 0x7FFFFFFF) >> 23); +} + +// Calculates and returns the log of |energy| in Q8. The input |energy| is +// supposed to be in Q(|q_domain|). +static int16_t LogOfEnergyInQ8(uint32_t energy, int q_domain) { + static const int16_t kLogLowValue = PART_LEN_SHIFT << 7; + int16_t log_energy_q8 = kLogLowValue; + if (energy > 0) { + int zeros = WebRtcSpl_NormU32(energy); + int16_t frac = ExtractFractionPart(energy, zeros); + // log2 of |energy| in Q8. + log_energy_q8 += ((31 - zeros) << 8) + frac - (q_domain << 8); + } + return log_energy_q8; +} + +// WebRtcAecm_CalcEnergies(...) +// +// This function calculates the log of energies for nearend, farend and estimated +// echoes. There is also an update of energy decision levels, i.e. internal VAD. +// +// +// @param aecm [i/o] Handle of the AECM instance. +// @param far_spectrum [in] Pointer to farend spectrum. +// @param far_q [in] Q-domain of farend spectrum. +// @param nearEner [in] Near end energy for current block in +// Q(aecm->dfaQDomain). +// @param echoEst [out] Estimated echo in Q(xfa_q+RESOLUTION_CHANNEL16). +// +void WebRtcAecm_CalcEnergies(AecmCore* aecm, + const uint16_t* far_spectrum, + const int16_t far_q, + const uint32_t nearEner, + int32_t* echoEst) { + // Local variables + uint32_t tmpAdapt = 0; + uint32_t tmpStored = 0; + uint32_t tmpFar = 0; + + int i; + + int16_t tmp16; + int16_t increase_max_shifts = 4; + int16_t decrease_max_shifts = 11; + int16_t increase_min_shifts = 11; + int16_t decrease_min_shifts = 3; + + // Get log of near end energy and store in buffer + + // Shift buffer + memmove(aecm->nearLogEnergy + 1, aecm->nearLogEnergy, + sizeof(int16_t) * (MAX_BUF_LEN - 1)); + + // Logarithm of integrated magnitude spectrum (nearEner) + aecm->nearLogEnergy[0] = LogOfEnergyInQ8(nearEner, aecm->dfaNoisyQDomain); + + WebRtcAecm_CalcLinearEnergies(aecm, far_spectrum, echoEst, &tmpFar, &tmpAdapt, &tmpStored); + + // Shift buffers + memmove(aecm->echoAdaptLogEnergy + 1, aecm->echoAdaptLogEnergy, + sizeof(int16_t) * (MAX_BUF_LEN - 1)); + memmove(aecm->echoStoredLogEnergy + 1, aecm->echoStoredLogEnergy, + sizeof(int16_t) * (MAX_BUF_LEN - 1)); + + // Logarithm of delayed far end energy + aecm->farLogEnergy = LogOfEnergyInQ8(tmpFar, far_q); + + // Logarithm of estimated echo energy through adapted channel + aecm->echoAdaptLogEnergy[0] = LogOfEnergyInQ8(tmpAdapt, + RESOLUTION_CHANNEL16 + far_q); + + // Logarithm of estimated echo energy through stored channel + aecm->echoStoredLogEnergy[0] = + LogOfEnergyInQ8(tmpStored, RESOLUTION_CHANNEL16 + far_q); + + // Update farend energy levels (min, max, vad, mse) + if (aecm->farLogEnergy > FAR_ENERGY_MIN) + { + if (aecm->startupState == 0) + { + increase_max_shifts = 2; + decrease_min_shifts = 2; + increase_min_shifts = 8; + } + + aecm->farEnergyMin = WebRtcAecm_AsymFilt(aecm->farEnergyMin, aecm->farLogEnergy, + increase_min_shifts, decrease_min_shifts); + aecm->farEnergyMax = WebRtcAecm_AsymFilt(aecm->farEnergyMax, aecm->farLogEnergy, + increase_max_shifts, decrease_max_shifts); + aecm->farEnergyMaxMin = (aecm->farEnergyMax - aecm->farEnergyMin); + + // Dynamic VAD region size + tmp16 = 2560 - aecm->farEnergyMin; + if (tmp16 > 0) + { + tmp16 = (int16_t)((tmp16 * FAR_ENERGY_VAD_REGION) >> 9); + } else + { + tmp16 = 0; + } + tmp16 += FAR_ENERGY_VAD_REGION; + + if ((aecm->startupState == 0) | (aecm->vadUpdateCount > 1024)) + { + // In startup phase or VAD update halted + aecm->farEnergyVAD = aecm->farEnergyMin + tmp16; + } else + { + if (aecm->farEnergyVAD > aecm->farLogEnergy) + { + aecm->farEnergyVAD += + (aecm->farLogEnergy + tmp16 - aecm->farEnergyVAD) >> 6; + aecm->vadUpdateCount = 0; + } else + { + aecm->vadUpdateCount++; + } + } + // Put MSE threshold higher than VAD + aecm->farEnergyMSE = aecm->farEnergyVAD + (1 << 8); + } + + // Update VAD variables + if (aecm->farLogEnergy > aecm->farEnergyVAD) + { + if ((aecm->startupState == 0) | (aecm->farEnergyMaxMin > FAR_ENERGY_DIFF)) + { + // We are in startup or have significant dynamics in input speech level + aecm->currentVADValue = 1; + } + } else + { + aecm->currentVADValue = 0; + } + if ((aecm->currentVADValue) && (aecm->firstVAD)) + { + aecm->firstVAD = 0; + if (aecm->echoAdaptLogEnergy[0] > aecm->nearLogEnergy[0]) + { + // The estimated echo has higher energy than the near end signal. + // This means that the initialization was too aggressive. Scale + // down by a factor 8 + for (i = 0; i < PART_LEN1; i++) + { + aecm->channelAdapt16[i] >>= 3; + } + // Compensate the adapted echo energy level accordingly. + aecm->echoAdaptLogEnergy[0] -= (3 << 8); + aecm->firstVAD = 1; + } + } +} + +// WebRtcAecm_CalcStepSize(...) +// +// This function calculates the step size used in channel estimation +// +// +// @param aecm [in] Handle of the AECM instance. +// @param mu [out] (Return value) Stepsize in log2(), i.e. number of shifts. +// +// +int16_t WebRtcAecm_CalcStepSize(AecmCore* const aecm) { + int32_t tmp32; + int16_t tmp16; + int16_t mu = MU_MAX; + + // Here we calculate the step size mu used in the + // following NLMS based Channel estimation algorithm + if (!aecm->currentVADValue) + { + // Far end energy level too low, no channel update + mu = 0; + } else if (aecm->startupState > 0) + { + if (aecm->farEnergyMin >= aecm->farEnergyMax) + { + mu = MU_MIN; + } else + { + tmp16 = (aecm->farLogEnergy - aecm->farEnergyMin); + tmp32 = tmp16 * MU_DIFF; + tmp32 = WebRtcSpl_DivW32W16(tmp32, aecm->farEnergyMaxMin); + mu = MU_MIN - 1 - (int16_t)(tmp32); + // The -1 is an alternative to rounding. This way we get a larger + // stepsize, so we in some sense compensate for truncation in NLMS + } + if (mu < MU_MAX) + { + mu = MU_MAX; // Equivalent with maximum step size of 2^-MU_MAX + } + } + + return mu; +} + +// WebRtcAecm_UpdateChannel(...) +// +// This function performs channel estimation. NLMS and decision on channel storage. +// +// +// @param aecm [i/o] Handle of the AECM instance. +// @param far_spectrum [in] Absolute value of the farend signal in Q(far_q) +// @param far_q [in] Q-domain of the farend signal +// @param dfa [in] Absolute value of the nearend signal (Q[aecm->dfaQDomain]) +// @param mu [in] NLMS step size. +// @param echoEst [i/o] Estimated echo in Q(far_q+RESOLUTION_CHANNEL16). +// +void WebRtcAecm_UpdateChannel(AecmCore* aecm, + const uint16_t* far_spectrum, + const int16_t far_q, + const uint16_t* const dfa, + const int16_t mu, + int32_t* echoEst) { + uint32_t tmpU32no1, tmpU32no2; + int32_t tmp32no1, tmp32no2; + int32_t mseStored; + int32_t mseAdapt; + + int i; + + int16_t zerosFar, zerosNum, zerosCh, zerosDfa; + int16_t shiftChFar, shiftNum, shift2ResChan; + int16_t tmp16no1; + int16_t xfaQ, dfaQ; + + // This is the channel estimation algorithm. It is base on NLMS but has a variable step + // length, which was calculated above. + if (mu) + { + for (i = 0; i < PART_LEN1; i++) + { + // Determine norm of channel and farend to make sure we don't get overflow in + // multiplication + zerosCh = WebRtcSpl_NormU32(aecm->channelAdapt32[i]); + zerosFar = WebRtcSpl_NormU32((uint32_t)far_spectrum[i]); + if (zerosCh + zerosFar > 31) + { + // Multiplication is safe + tmpU32no1 = WEBRTC_SPL_UMUL_32_16(aecm->channelAdapt32[i], + far_spectrum[i]); + shiftChFar = 0; + } else + { + // We need to shift down before multiplication + shiftChFar = 32 - zerosCh - zerosFar; + tmpU32no1 = (aecm->channelAdapt32[i] >> shiftChFar) * + far_spectrum[i]; + } + // Determine Q-domain of numerator + zerosNum = WebRtcSpl_NormU32(tmpU32no1); + if (dfa[i]) + { + zerosDfa = WebRtcSpl_NormU32((uint32_t)dfa[i]); + } else + { + zerosDfa = 32; + } + tmp16no1 = zerosDfa - 2 + aecm->dfaNoisyQDomain - + RESOLUTION_CHANNEL32 - far_q + shiftChFar; + if (zerosNum > tmp16no1 + 1) + { + xfaQ = tmp16no1; + dfaQ = zerosDfa - 2; + } else + { + xfaQ = zerosNum - 2; + dfaQ = RESOLUTION_CHANNEL32 + far_q - aecm->dfaNoisyQDomain - + shiftChFar + xfaQ; + } + // Add in the same Q-domain + tmpU32no1 = WEBRTC_SPL_SHIFT_W32(tmpU32no1, xfaQ); + tmpU32no2 = WEBRTC_SPL_SHIFT_W32((uint32_t)dfa[i], dfaQ); + tmp32no1 = (int32_t)tmpU32no2 - (int32_t)tmpU32no1; + zerosNum = WebRtcSpl_NormW32(tmp32no1); + if ((tmp32no1) && (far_spectrum[i] > (CHANNEL_VAD << far_q))) + { + // + // Update is needed + // + // This is what we would like to compute + // + // tmp32no1 = dfa[i] - (aecm->channelAdapt[i] * far_spectrum[i]) + // tmp32norm = (i + 1) + // aecm->channelAdapt[i] += (2^mu) * tmp32no1 + // / (tmp32norm * far_spectrum[i]) + // + + // Make sure we don't get overflow in multiplication. + if (zerosNum + zerosFar > 31) + { + if (tmp32no1 > 0) + { + tmp32no2 = (int32_t)WEBRTC_SPL_UMUL_32_16(tmp32no1, + far_spectrum[i]); + } else + { + tmp32no2 = -(int32_t)WEBRTC_SPL_UMUL_32_16(-tmp32no1, + far_spectrum[i]); + } + shiftNum = 0; + } else + { + shiftNum = 32 - (zerosNum + zerosFar); + if (tmp32no1 > 0) + { + tmp32no2 = (tmp32no1 >> shiftNum) * far_spectrum[i]; + } else + { + tmp32no2 = -((-tmp32no1 >> shiftNum) * far_spectrum[i]); + } + } + // Normalize with respect to frequency bin + tmp32no2 = WebRtcSpl_DivW32W16(tmp32no2, i + 1); + // Make sure we are in the right Q-domain + shift2ResChan = shiftNum + shiftChFar - xfaQ - mu - ((30 - zerosFar) << 1); + if (WebRtcSpl_NormW32(tmp32no2) < shift2ResChan) + { + tmp32no2 = WEBRTC_SPL_WORD32_MAX; + } else + { + tmp32no2 = WEBRTC_SPL_SHIFT_W32(tmp32no2, shift2ResChan); + } + aecm->channelAdapt32[i] = + WebRtcSpl_AddSatW32(aecm->channelAdapt32[i], tmp32no2); + if (aecm->channelAdapt32[i] < 0) + { + // We can never have negative channel gain + aecm->channelAdapt32[i] = 0; + } + aecm->channelAdapt16[i] = + (int16_t)(aecm->channelAdapt32[i] >> 16); + } + } + } + // END: Adaptive channel update + + // Determine if we should store or restore the channel + if ((aecm->startupState == 0) & (aecm->currentVADValue)) + { + // During startup we store the channel every block, + // and we recalculate echo estimate + WebRtcAecm_StoreAdaptiveChannel(aecm, far_spectrum, echoEst); + } else + { + if (aecm->farLogEnergy < aecm->farEnergyMSE) + { + aecm->mseChannelCount = 0; + } else + { + aecm->mseChannelCount++; + } + // Enough data for validation. Store channel if we can. + if (aecm->mseChannelCount >= (MIN_MSE_COUNT + 10)) + { + // We have enough data. + // Calculate MSE of "Adapt" and "Stored" versions. + // It is actually not MSE, but average absolute error. + mseStored = 0; + mseAdapt = 0; + for (i = 0; i < MIN_MSE_COUNT; i++) + { + tmp32no1 = ((int32_t)aecm->echoStoredLogEnergy[i] + - (int32_t)aecm->nearLogEnergy[i]); + tmp32no2 = WEBRTC_SPL_ABS_W32(tmp32no1); + mseStored += tmp32no2; + + tmp32no1 = ((int32_t)aecm->echoAdaptLogEnergy[i] + - (int32_t)aecm->nearLogEnergy[i]); + tmp32no2 = WEBRTC_SPL_ABS_W32(tmp32no1); + mseAdapt += tmp32no2; + } + if (((mseStored << MSE_RESOLUTION) < (MIN_MSE_DIFF * mseAdapt)) + & ((aecm->mseStoredOld << MSE_RESOLUTION) < (MIN_MSE_DIFF + * aecm->mseAdaptOld))) + { + // The stored channel has a significantly lower MSE than the adaptive one for + // two consecutive calculations. Reset the adaptive channel. + WebRtcAecm_ResetAdaptiveChannel(aecm); + } else if (((MIN_MSE_DIFF * mseStored) > (mseAdapt << MSE_RESOLUTION)) & (mseAdapt + < aecm->mseThreshold) & (aecm->mseAdaptOld < aecm->mseThreshold)) + { + // The adaptive channel has a significantly lower MSE than the stored one. + // The MSE for the adaptive channel has also been low for two consecutive + // calculations. Store the adaptive channel. + WebRtcAecm_StoreAdaptiveChannel(aecm, far_spectrum, echoEst); + + // Update threshold + if (aecm->mseThreshold == WEBRTC_SPL_WORD32_MAX) + { + aecm->mseThreshold = (mseAdapt + aecm->mseAdaptOld); + } else + { + int scaled_threshold = aecm->mseThreshold * 5 / 8; + aecm->mseThreshold += + ((mseAdapt - scaled_threshold) * 205) >> 8; + } + + } + + // Reset counter + aecm->mseChannelCount = 0; + + // Store the MSE values. + aecm->mseStoredOld = mseStored; + aecm->mseAdaptOld = mseAdapt; + } + } + // END: Determine if we should store or reset channel estimate. +} + +// CalcSuppressionGain(...) +// +// This function calculates the suppression gain that is used in the Wiener filter. +// +// +// @param aecm [i/n] Handle of the AECM instance. +// @param supGain [out] (Return value) Suppression gain with which to scale the noise +// level (Q14). +// +// +int16_t WebRtcAecm_CalcSuppressionGain(AecmCore* const aecm) { + int32_t tmp32no1; + + int16_t supGain = SUPGAIN_DEFAULT; + int16_t tmp16no1; + int16_t dE = 0; + + // Determine suppression gain used in the Wiener filter. The gain is based on a mix of far + // end energy and echo estimation error. + // Adjust for the far end signal level. A low signal level indicates no far end signal, + // hence we set the suppression gain to 0 + if (!aecm->currentVADValue) + { + supGain = 0; + } else + { + // Adjust for possible double talk. If we have large variations in estimation error we + // likely have double talk (or poor channel). + tmp16no1 = (aecm->nearLogEnergy[0] - aecm->echoStoredLogEnergy[0] - ENERGY_DEV_OFFSET); + dE = WEBRTC_SPL_ABS_W16(tmp16no1); + + if (dE < ENERGY_DEV_TOL) + { + // Likely no double talk. The better estimation, the more we can suppress signal. + // Update counters + if (dE < SUPGAIN_EPC_DT) + { + tmp32no1 = aecm->supGainErrParamDiffAB * dE; + tmp32no1 += (SUPGAIN_EPC_DT >> 1); + tmp16no1 = (int16_t)WebRtcSpl_DivW32W16(tmp32no1, SUPGAIN_EPC_DT); + supGain = aecm->supGainErrParamA - tmp16no1; + } else + { + tmp32no1 = aecm->supGainErrParamDiffBD * (ENERGY_DEV_TOL - dE); + tmp32no1 += ((ENERGY_DEV_TOL - SUPGAIN_EPC_DT) >> 1); + tmp16no1 = (int16_t)WebRtcSpl_DivW32W16(tmp32no1, (ENERGY_DEV_TOL + - SUPGAIN_EPC_DT)); + supGain = aecm->supGainErrParamD + tmp16no1; + } + } else + { + // Likely in double talk. Use default value + supGain = aecm->supGainErrParamD; + } + } + + if (supGain > aecm->supGainOld) + { + tmp16no1 = supGain; + } else + { + tmp16no1 = aecm->supGainOld; + } + aecm->supGainOld = supGain; + if (tmp16no1 < aecm->supGain) + { + aecm->supGain += (int16_t)((tmp16no1 - aecm->supGain) >> 4); + } else + { + aecm->supGain += (int16_t)((tmp16no1 - aecm->supGain) >> 4); + } + + // END: Update suppression gain + + return aecm->supGain; +} + +void WebRtcAecm_BufferFarFrame(AecmCore* const aecm, + const int16_t* const farend, + const int farLen) { + int writeLen = farLen, writePos = 0; + + // Check if the write position must be wrapped + while (aecm->farBufWritePos + writeLen > FAR_BUF_LEN) + { + // Write to remaining buffer space before wrapping + writeLen = FAR_BUF_LEN - aecm->farBufWritePos; + memcpy(aecm->farBuf + aecm->farBufWritePos, farend + writePos, + sizeof(int16_t) * writeLen); + aecm->farBufWritePos = 0; + writePos = writeLen; + writeLen = farLen - writeLen; + } + + memcpy(aecm->farBuf + aecm->farBufWritePos, farend + writePos, + sizeof(int16_t) * writeLen); + aecm->farBufWritePos += writeLen; +} + +void WebRtcAecm_FetchFarFrame(AecmCore* const aecm, + int16_t* const farend, + const int farLen, + const int knownDelay) { + int readLen = farLen; + int readPos = 0; + int delayChange = knownDelay - aecm->lastKnownDelay; + + aecm->farBufReadPos -= delayChange; + + // Check if delay forces a read position wrap + while (aecm->farBufReadPos < 0) + { + aecm->farBufReadPos += FAR_BUF_LEN; + } + while (aecm->farBufReadPos > FAR_BUF_LEN - 1) + { + aecm->farBufReadPos -= FAR_BUF_LEN; + } + + aecm->lastKnownDelay = knownDelay; + + // Check if read position must be wrapped + while (aecm->farBufReadPos + readLen > FAR_BUF_LEN) + { + + // Read from remaining buffer space before wrapping + readLen = FAR_BUF_LEN - aecm->farBufReadPos; + memcpy(farend + readPos, aecm->farBuf + aecm->farBufReadPos, + sizeof(int16_t) * readLen); + aecm->farBufReadPos = 0; + readPos = readLen; + readLen = farLen - readLen; + } + memcpy(farend + readPos, aecm->farBuf + aecm->farBufReadPos, + sizeof(int16_t) * readLen); + aecm->farBufReadPos += readLen; +} |