/* * Copyright (c) 2013 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 #include #include "modules/audio_processing/aecm/aecm_core.h" extern "C" { #include "common_audio/ring_buffer.h" #include "common_audio/signal_processing/include/real_fft.h" } #include "modules/audio_processing/aecm/echo_control_mobile.h" #include "modules/audio_processing/utility/delay_estimator_wrapper.h" extern "C" { #include "system_wrappers/include/cpu_features_wrapper.h" } #include "rtc_base/checks.h" #include "rtc_base/numerics/safe_conversions.h" #include "rtc_base/sanitizer.h" namespace webrtc { namespace { // Square root of Hanning window in Q14. static const ALIGN8_BEG int16_t WebRtcAecm_kSqrtHanning[] ALIGN8_END = { 0, 399, 798, 1196, 1594, 1990, 2386, 2780, 3172, 3562, 3951, 4337, 4720, 5101, 5478, 5853, 6224, 6591, 6954, 7313, 7668, 8019, 8364, 8705, 9040, 9370, 9695, 10013, 10326, 10633, 10933, 11227, 11514, 11795, 12068, 12335, 12594, 12845, 13089, 13325, 13553, 13773, 13985, 14189, 14384, 14571, 14749, 14918, 15079, 15231, 15373, 15506, 15631, 15746, 15851, 15947, 16034, 16111, 16179, 16237, 16286, 16325, 16354, 16373, 16384}; #ifdef AECM_WITH_ABS_APPROX // Q15 alpha = 0.99439986968132 const Factor for magnitude approximation static const uint16_t kAlpha1 = 32584; // Q15 beta = 0.12967166976970 const Factor for magnitude approximation static const uint16_t kBeta1 = 4249; // Q15 alpha = 0.94234827210087 const Factor for magnitude approximation static const uint16_t kAlpha2 = 30879; // Q15 beta = 0.33787806009150 const Factor for magnitude approximation static const uint16_t kBeta2 = 11072; // Q15 alpha = 0.82247698684306 const Factor for magnitude approximation static const uint16_t kAlpha3 = 26951; // Q15 beta = 0.57762063060713 const Factor for magnitude approximation static const uint16_t kBeta3 = 18927; #endif static const int16_t kNoiseEstQDomain = 15; static const int16_t kNoiseEstIncCount = 5; static void ComfortNoise(AecmCore* aecm, const uint16_t* dfa, ComplexInt16* out, const int16_t* lambda) { int16_t i; int16_t tmp16; int32_t tmp32; int16_t randW16[PART_LEN]; int16_t uReal[PART_LEN1]; int16_t uImag[PART_LEN1]; int32_t outLShift32; int16_t noiseRShift16[PART_LEN1]; int16_t shiftFromNearToNoise = kNoiseEstQDomain - aecm->dfaCleanQDomain; int16_t minTrackShift; RTC_DCHECK_GE(shiftFromNearToNoise, 0); RTC_DCHECK_LT(shiftFromNearToNoise, 16); if (aecm->noiseEstCtr < 100) { // Track the minimum more quickly initially. aecm->noiseEstCtr++; minTrackShift = 6; } else { minTrackShift = 9; } // Estimate noise power. for (i = 0; i < PART_LEN1; i++) { // Shift to the noise domain. tmp32 = (int32_t)dfa[i]; outLShift32 = tmp32 << shiftFromNearToNoise; if (outLShift32 < aecm->noiseEst[i]) { // Reset "too low" counter aecm->noiseEstTooLowCtr[i] = 0; // Track the minimum. if (aecm->noiseEst[i] < (1 << minTrackShift)) { // For small values, decrease noiseEst[i] every // `kNoiseEstIncCount` block. The regular approach below can not // go further down due to truncation. aecm->noiseEstTooHighCtr[i]++; if (aecm->noiseEstTooHighCtr[i] >= kNoiseEstIncCount) { aecm->noiseEst[i]--; aecm->noiseEstTooHighCtr[i] = 0; // Reset the counter } } else { aecm->noiseEst[i] -= ((aecm->noiseEst[i] - outLShift32) >> minTrackShift); } } else { // Reset "too high" counter aecm->noiseEstTooHighCtr[i] = 0; // Ramp slowly upwards until we hit the minimum again. if ((aecm->noiseEst[i] >> 19) > 0) { // Avoid overflow. // Multiplication with 2049 will cause wrap around. Scale // down first and then multiply aecm->noiseEst[i] >>= 11; aecm->noiseEst[i] *= 2049; } else if ((aecm->noiseEst[i] >> 11) > 0) { // Large enough for relative increase aecm->noiseEst[i] *= 2049; aecm->noiseEst[i] >>= 11; } else { // Make incremental increases based on size every // `kNoiseEstIncCount` block aecm->noiseEstTooLowCtr[i]++; if (aecm->noiseEstTooLowCtr[i] >= kNoiseEstIncCount) { aecm->noiseEst[i] += (aecm->noiseEst[i] >> 9) + 1; aecm->noiseEstTooLowCtr[i] = 0; // Reset counter } } } } for (i = 0; i < PART_LEN1; i++) { tmp32 = aecm->noiseEst[i] >> shiftFromNearToNoise; if (tmp32 > 32767) { tmp32 = 32767; aecm->noiseEst[i] = tmp32 << shiftFromNearToNoise; } noiseRShift16[i] = (int16_t)tmp32; tmp16 = ONE_Q14 - lambda[i]; noiseRShift16[i] = (int16_t)((tmp16 * noiseRShift16[i]) >> 14); } // Generate a uniform random array on [0 2^15-1]. WebRtcSpl_RandUArray(randW16, PART_LEN, &aecm->seed); // Generate noise according to estimated energy. uReal[0] = 0; // Reject LF noise. uImag[0] = 0; for (i = 1; i < PART_LEN1; i++) { // Get a random index for the cos and sin tables over [0 359]. tmp16 = (int16_t)((359 * randW16[i - 1]) >> 15); // Tables are in Q13. uReal[i] = (int16_t)((noiseRShift16[i] * WebRtcAecm_kCosTable[tmp16]) >> 13); uImag[i] = (int16_t)((-noiseRShift16[i] * WebRtcAecm_kSinTable[tmp16]) >> 13); } uImag[PART_LEN] = 0; for (i = 0; i < PART_LEN1; i++) { out[i].real = WebRtcSpl_AddSatW16(out[i].real, uReal[i]); out[i].imag = WebRtcSpl_AddSatW16(out[i].imag, uImag[i]); } } static void WindowAndFFT(AecmCore* aecm, int16_t* fft, const int16_t* time_signal, ComplexInt16* freq_signal, int time_signal_scaling) { int i = 0; // FFT of signal for (i = 0; i < PART_LEN; i++) { // Window time domain signal and insert into real part of // transformation array `fft` int16_t scaled_time_signal = time_signal[i] * (1 << time_signal_scaling); fft[i] = (int16_t)((scaled_time_signal * WebRtcAecm_kSqrtHanning[i]) >> 14); scaled_time_signal = time_signal[i + PART_LEN] * (1 << time_signal_scaling); fft[PART_LEN + i] = (int16_t)( (scaled_time_signal * WebRtcAecm_kSqrtHanning[PART_LEN - i]) >> 14); } // Do forward FFT, then take only the first PART_LEN complex samples, // and change signs of the imaginary parts. WebRtcSpl_RealForwardFFT(aecm->real_fft, fft, (int16_t*)freq_signal); for (i = 0; i < PART_LEN; i++) { freq_signal[i].imag = -freq_signal[i].imag; } } static void InverseFFTAndWindow(AecmCore* aecm, int16_t* fft, ComplexInt16* efw, int16_t* output, const int16_t* nearendClean) { int i, j, outCFFT; int32_t tmp32no1; // Reuse `efw` for the inverse FFT output after transferring // the contents to `fft`. int16_t* ifft_out = (int16_t*)efw; // Synthesis for (i = 1, j = 2; i < PART_LEN; i += 1, j += 2) { fft[j] = efw[i].real; fft[j + 1] = -efw[i].imag; } fft[0] = efw[0].real; fft[1] = -efw[0].imag; fft[PART_LEN2] = efw[PART_LEN].real; fft[PART_LEN2 + 1] = -efw[PART_LEN].imag; // Inverse FFT. Keep outCFFT to scale the samples in the next block. outCFFT = WebRtcSpl_RealInverseFFT(aecm->real_fft, fft, ifft_out); for (i = 0; i < PART_LEN; i++) { ifft_out[i] = (int16_t)WEBRTC_SPL_MUL_16_16_RSFT_WITH_ROUND( ifft_out[i], WebRtcAecm_kSqrtHanning[i], 14); tmp32no1 = WEBRTC_SPL_SHIFT_W32((int32_t)ifft_out[i], outCFFT - aecm->dfaCleanQDomain); output[i] = (int16_t)WEBRTC_SPL_SAT(WEBRTC_SPL_WORD16_MAX, tmp32no1 + aecm->outBuf[i], WEBRTC_SPL_WORD16_MIN); tmp32no1 = (ifft_out[PART_LEN + i] * WebRtcAecm_kSqrtHanning[PART_LEN - i]) >> 14; tmp32no1 = WEBRTC_SPL_SHIFT_W32(tmp32no1, outCFFT - aecm->dfaCleanQDomain); aecm->outBuf[i] = (int16_t)WEBRTC_SPL_SAT(WEBRTC_SPL_WORD16_MAX, tmp32no1, WEBRTC_SPL_WORD16_MIN); } // Copy the current block to the old position // (aecm->outBuf is shifted elsewhere) memcpy(aecm->xBuf, aecm->xBuf + PART_LEN, sizeof(int16_t) * PART_LEN); memcpy(aecm->dBufNoisy, aecm->dBufNoisy + PART_LEN, sizeof(int16_t) * PART_LEN); if (nearendClean != NULL) { memcpy(aecm->dBufClean, aecm->dBufClean + PART_LEN, sizeof(int16_t) * PART_LEN); } } // Transforms a time domain signal into the frequency domain, outputting the // complex valued signal, absolute value and sum of absolute values. // // time_signal [in] Pointer to time domain signal // freq_signal_real [out] Pointer to real part of frequency domain array // freq_signal_imag [out] Pointer to imaginary part of frequency domain // array // freq_signal_abs [out] Pointer to absolute value of frequency domain // array // freq_signal_sum_abs [out] Pointer to the sum of all absolute values in // the frequency domain array // return value The Q-domain of current frequency values // static int TimeToFrequencyDomain(AecmCore* aecm, const int16_t* time_signal, ComplexInt16* freq_signal, uint16_t* freq_signal_abs, uint32_t* freq_signal_sum_abs) { int i = 0; int time_signal_scaling = 0; int32_t tmp32no1 = 0; int32_t tmp32no2 = 0; // In fft_buf, +16 for 32-byte alignment. int16_t fft_buf[PART_LEN4 + 16]; int16_t* fft = (int16_t*)(((uintptr_t)fft_buf + 31) & ~31); int16_t tmp16no1; #ifndef WEBRTC_ARCH_ARM_V7 int16_t tmp16no2; #endif #ifdef AECM_WITH_ABS_APPROX int16_t max_value = 0; int16_t min_value = 0; uint16_t alpha = 0; uint16_t beta = 0; #endif #ifdef AECM_DYNAMIC_Q tmp16no1 = WebRtcSpl_MaxAbsValueW16(time_signal, PART_LEN2); time_signal_scaling = WebRtcSpl_NormW16(tmp16no1); #endif WindowAndFFT(aecm, fft, time_signal, freq_signal, time_signal_scaling); // Extract imaginary and real part, calculate the magnitude for // all frequency bins freq_signal[0].imag = 0; freq_signal[PART_LEN].imag = 0; freq_signal_abs[0] = (uint16_t)WEBRTC_SPL_ABS_W16(freq_signal[0].real); freq_signal_abs[PART_LEN] = (uint16_t)WEBRTC_SPL_ABS_W16(freq_signal[PART_LEN].real); (*freq_signal_sum_abs) = (uint32_t)(freq_signal_abs[0]) + (uint32_t)(freq_signal_abs[PART_LEN]); for (i = 1; i < PART_LEN; i++) { if (freq_signal[i].real == 0) { freq_signal_abs[i] = (uint16_t)WEBRTC_SPL_ABS_W16(freq_signal[i].imag); } else if (freq_signal[i].imag == 0) { freq_signal_abs[i] = (uint16_t)WEBRTC_SPL_ABS_W16(freq_signal[i].real); } else { // Approximation for magnitude of complex fft output // magn = sqrt(real^2 + imag^2) // magn ~= alpha * max(`imag`,`real`) + beta * min(`imag`,`real`) // // The parameters alpha and beta are stored in Q15 #ifdef AECM_WITH_ABS_APPROX tmp16no1 = WEBRTC_SPL_ABS_W16(freq_signal[i].real); tmp16no2 = WEBRTC_SPL_ABS_W16(freq_signal[i].imag); if (tmp16no1 > tmp16no2) { max_value = tmp16no1; min_value = tmp16no2; } else { max_value = tmp16no2; min_value = tmp16no1; } // Magnitude in Q(-6) if ((max_value >> 2) > min_value) { alpha = kAlpha1; beta = kBeta1; } else if ((max_value >> 1) > min_value) { alpha = kAlpha2; beta = kBeta2; } else { alpha = kAlpha3; beta = kBeta3; } tmp16no1 = (int16_t)((max_value * alpha) >> 15); tmp16no2 = (int16_t)((min_value * beta) >> 15); freq_signal_abs[i] = (uint16_t)tmp16no1 + (uint16_t)tmp16no2; #else #ifdef WEBRTC_ARCH_ARM_V7 __asm __volatile( "smulbb %[tmp32no1], %[real], %[real]\n\t" "smlabb %[tmp32no2], %[imag], %[imag], %[tmp32no1]\n\t" : [tmp32no1] "+&r"(tmp32no1), [tmp32no2] "=r"(tmp32no2) : [real] "r"(freq_signal[i].real), [imag] "r"(freq_signal[i].imag)); #else tmp16no1 = WEBRTC_SPL_ABS_W16(freq_signal[i].real); tmp16no2 = WEBRTC_SPL_ABS_W16(freq_signal[i].imag); tmp32no1 = tmp16no1 * tmp16no1; tmp32no2 = tmp16no2 * tmp16no2; tmp32no2 = WebRtcSpl_AddSatW32(tmp32no1, tmp32no2); #endif // WEBRTC_ARCH_ARM_V7 tmp32no1 = WebRtcSpl_SqrtFloor(tmp32no2); freq_signal_abs[i] = (uint16_t)tmp32no1; #endif // AECM_WITH_ABS_APPROX } (*freq_signal_sum_abs) += (uint32_t)freq_signal_abs[i]; } return time_signal_scaling; } } // namespace int RTC_NO_SANITIZE("signed-integer-overflow") // bugs.webrtc.org/8200 WebRtcAecm_ProcessBlock(AecmCore* aecm, const int16_t* farend, const int16_t* nearendNoisy, const int16_t* nearendClean, int16_t* output) { int i; uint32_t xfaSum; uint32_t dfaNoisySum; uint32_t dfaCleanSum; uint32_t echoEst32Gained; uint32_t tmpU32; int32_t tmp32no1; uint16_t xfa[PART_LEN1]; uint16_t dfaNoisy[PART_LEN1]; uint16_t dfaClean[PART_LEN1]; uint16_t* ptrDfaClean = dfaClean; const uint16_t* far_spectrum_ptr = NULL; // 32 byte aligned buffers (with +8 or +16). // TODO(kma): define fft with ComplexInt16. int16_t fft_buf[PART_LEN4 + 2 + 16]; // +2 to make a loop safe. int32_t echoEst32_buf[PART_LEN1 + 8]; int32_t dfw_buf[PART_LEN2 + 8]; int32_t efw_buf[PART_LEN2 + 8]; int16_t* fft = (int16_t*)(((uintptr_t)fft_buf + 31) & ~31); int32_t* echoEst32 = (int32_t*)(((uintptr_t)echoEst32_buf + 31) & ~31); ComplexInt16* dfw = (ComplexInt16*)(((uintptr_t)dfw_buf + 31) & ~31); ComplexInt16* efw = (ComplexInt16*)(((uintptr_t)efw_buf + 31) & ~31); int16_t hnl[PART_LEN1]; int16_t numPosCoef = 0; int16_t nlpGain = ONE_Q14; int delay; int16_t tmp16no1; int16_t tmp16no2; int16_t mu; int16_t supGain; int16_t zeros32, zeros16; int16_t zerosDBufNoisy, zerosDBufClean, zerosXBuf; int far_q; int16_t resolutionDiff, qDomainDiff, dfa_clean_q_domain_diff; const int kMinPrefBand = 4; const int kMaxPrefBand = 24; int32_t avgHnl32 = 0; // Determine startup state. There are three states: // (0) the first CONV_LEN blocks // (1) another CONV_LEN blocks // (2) the rest if (aecm->startupState < 2) { aecm->startupState = (aecm->totCount >= CONV_LEN) + (aecm->totCount >= CONV_LEN2); } // END: Determine startup state // Buffer near and far end signals memcpy(aecm->xBuf + PART_LEN, farend, sizeof(int16_t) * PART_LEN); memcpy(aecm->dBufNoisy + PART_LEN, nearendNoisy, sizeof(int16_t) * PART_LEN); if (nearendClean != NULL) { memcpy(aecm->dBufClean + PART_LEN, nearendClean, sizeof(int16_t) * PART_LEN); } // Transform far end signal from time domain to frequency domain. far_q = TimeToFrequencyDomain(aecm, aecm->xBuf, dfw, xfa, &xfaSum); // Transform noisy near end signal from time domain to frequency domain. zerosDBufNoisy = TimeToFrequencyDomain(aecm, aecm->dBufNoisy, dfw, dfaNoisy, &dfaNoisySum); aecm->dfaNoisyQDomainOld = aecm->dfaNoisyQDomain; aecm->dfaNoisyQDomain = (int16_t)zerosDBufNoisy; if (nearendClean == NULL) { ptrDfaClean = dfaNoisy; aecm->dfaCleanQDomainOld = aecm->dfaNoisyQDomainOld; aecm->dfaCleanQDomain = aecm->dfaNoisyQDomain; dfaCleanSum = dfaNoisySum; } else { // Transform clean near end signal from time domain to frequency domain. zerosDBufClean = TimeToFrequencyDomain(aecm, aecm->dBufClean, dfw, dfaClean, &dfaCleanSum); aecm->dfaCleanQDomainOld = aecm->dfaCleanQDomain; aecm->dfaCleanQDomain = (int16_t)zerosDBufClean; } // Get the delay // Save far-end history and estimate delay WebRtcAecm_UpdateFarHistory(aecm, xfa, far_q); if (WebRtc_AddFarSpectrumFix(aecm->delay_estimator_farend, xfa, PART_LEN1, far_q) == -1) { return -1; } delay = WebRtc_DelayEstimatorProcessFix(aecm->delay_estimator, dfaNoisy, PART_LEN1, zerosDBufNoisy); if (delay == -1) { return -1; } else if (delay == -2) { // If the delay is unknown, we assume zero. // NOTE: this will have to be adjusted if we ever add lookahead. delay = 0; } if (aecm->fixedDelay >= 0) { // Use fixed delay delay = aecm->fixedDelay; } // Get aligned far end spectrum far_spectrum_ptr = WebRtcAecm_AlignedFarend(aecm, &far_q, delay); zerosXBuf = (int16_t)far_q; if (far_spectrum_ptr == NULL) { return -1; } // Calculate log(energy) and update energy threshold levels WebRtcAecm_CalcEnergies(aecm, far_spectrum_ptr, zerosXBuf, dfaNoisySum, echoEst32); // Calculate stepsize mu = WebRtcAecm_CalcStepSize(aecm); // Update counters aecm->totCount++; // This is the channel estimation algorithm. // It is base on NLMS but has a variable step length, // which was calculated above. WebRtcAecm_UpdateChannel(aecm, far_spectrum_ptr, zerosXBuf, dfaNoisy, mu, echoEst32); supGain = WebRtcAecm_CalcSuppressionGain(aecm); // Calculate Wiener filter hnl[] for (i = 0; i < PART_LEN1; i++) { // Far end signal through channel estimate in Q8 // How much can we shift right to preserve resolution tmp32no1 = echoEst32[i] - aecm->echoFilt[i]; aecm->echoFilt[i] += rtc::dchecked_cast((int64_t{tmp32no1} * 50) >> 8); zeros32 = WebRtcSpl_NormW32(aecm->echoFilt[i]) + 1; zeros16 = WebRtcSpl_NormW16(supGain) + 1; if (zeros32 + zeros16 > 16) { // Multiplication is safe // Result in // Q(RESOLUTION_CHANNEL+RESOLUTION_SUPGAIN+ // aecm->xfaQDomainBuf[diff]) echoEst32Gained = WEBRTC_SPL_UMUL_32_16((uint32_t)aecm->echoFilt[i], (uint16_t)supGain); resolutionDiff = 14 - RESOLUTION_CHANNEL16 - RESOLUTION_SUPGAIN; resolutionDiff += (aecm->dfaCleanQDomain - zerosXBuf); } else { tmp16no1 = 17 - zeros32 - zeros16; resolutionDiff = 14 + tmp16no1 - RESOLUTION_CHANNEL16 - RESOLUTION_SUPGAIN; resolutionDiff += (aecm->dfaCleanQDomain - zerosXBuf); if (zeros32 > tmp16no1) { echoEst32Gained = WEBRTC_SPL_UMUL_32_16((uint32_t)aecm->echoFilt[i], supGain >> tmp16no1); } else { // Result in Q-(RESOLUTION_CHANNEL+RESOLUTION_SUPGAIN-16) echoEst32Gained = (aecm->echoFilt[i] >> tmp16no1) * supGain; } } zeros16 = WebRtcSpl_NormW16(aecm->nearFilt[i]); RTC_DCHECK_GE(zeros16, 0); // `zeros16` is a norm, hence non-negative. dfa_clean_q_domain_diff = aecm->dfaCleanQDomain - aecm->dfaCleanQDomainOld; if (zeros16 < dfa_clean_q_domain_diff && aecm->nearFilt[i]) { tmp16no1 = aecm->nearFilt[i] * (1 << zeros16); qDomainDiff = zeros16 - dfa_clean_q_domain_diff; tmp16no2 = ptrDfaClean[i] >> -qDomainDiff; } else { tmp16no1 = dfa_clean_q_domain_diff < 0 ? aecm->nearFilt[i] >> -dfa_clean_q_domain_diff : aecm->nearFilt[i] * (1 << dfa_clean_q_domain_diff); qDomainDiff = 0; tmp16no2 = ptrDfaClean[i]; } tmp32no1 = (int32_t)(tmp16no2 - tmp16no1); tmp16no2 = (int16_t)(tmp32no1 >> 4); tmp16no2 += tmp16no1; zeros16 = WebRtcSpl_NormW16(tmp16no2); if ((tmp16no2) & (-qDomainDiff > zeros16)) { aecm->nearFilt[i] = WEBRTC_SPL_WORD16_MAX; } else { aecm->nearFilt[i] = qDomainDiff < 0 ? tmp16no2 * (1 << -qDomainDiff) : tmp16no2 >> qDomainDiff; } // Wiener filter coefficients, resulting hnl in Q14 if (echoEst32Gained == 0) { hnl[i] = ONE_Q14; } else if (aecm->nearFilt[i] == 0) { hnl[i] = 0; } else { // Multiply the suppression gain // Rounding echoEst32Gained += (uint32_t)(aecm->nearFilt[i] >> 1); tmpU32 = WebRtcSpl_DivU32U16(echoEst32Gained, (uint16_t)aecm->nearFilt[i]); // Current resolution is // Q-(RESOLUTION_CHANNEL+RESOLUTION_SUPGAIN- max(0,17-zeros16- zeros32)) // Make sure we are in Q14 tmp32no1 = (int32_t)WEBRTC_SPL_SHIFT_W32(tmpU32, resolutionDiff); if (tmp32no1 > ONE_Q14) { hnl[i] = 0; } else if (tmp32no1 < 0) { hnl[i] = ONE_Q14; } else { // 1-echoEst/dfa hnl[i] = ONE_Q14 - (int16_t)tmp32no1; if (hnl[i] < 0) { hnl[i] = 0; } } } if (hnl[i]) { numPosCoef++; } } // Only in wideband. Prevent the gain in upper band from being larger than // in lower band. if (aecm->mult == 2) { // TODO(bjornv): Investigate if the scaling of hnl[i] below can cause // speech distortion in double-talk. for (i = 0; i < PART_LEN1; i++) { hnl[i] = (int16_t)((hnl[i] * hnl[i]) >> 14); } for (i = kMinPrefBand; i <= kMaxPrefBand; i++) { avgHnl32 += (int32_t)hnl[i]; } RTC_DCHECK_GT(kMaxPrefBand - kMinPrefBand + 1, 0); avgHnl32 /= (kMaxPrefBand - kMinPrefBand + 1); for (i = kMaxPrefBand; i < PART_LEN1; i++) { if (hnl[i] > (int16_t)avgHnl32) { hnl[i] = (int16_t)avgHnl32; } } } // Calculate NLP gain, result is in Q14 if (aecm->nlpFlag) { for (i = 0; i < PART_LEN1; i++) { // Truncate values close to zero and one. if (hnl[i] > NLP_COMP_HIGH) { hnl[i] = ONE_Q14; } else if (hnl[i] < NLP_COMP_LOW) { hnl[i] = 0; } // Remove outliers if (numPosCoef < 3) { nlpGain = 0; } else { nlpGain = ONE_Q14; } // NLP if ((hnl[i] == ONE_Q14) && (nlpGain == ONE_Q14)) { hnl[i] = ONE_Q14; } else { hnl[i] = (int16_t)((hnl[i] * nlpGain) >> 14); } // multiply with Wiener coefficients efw[i].real = (int16_t)( WEBRTC_SPL_MUL_16_16_RSFT_WITH_ROUND(dfw[i].real, hnl[i], 14)); efw[i].imag = (int16_t)( WEBRTC_SPL_MUL_16_16_RSFT_WITH_ROUND(dfw[i].imag, hnl[i], 14)); } } else { // multiply with Wiener coefficients for (i = 0; i < PART_LEN1; i++) { efw[i].real = (int16_t)( WEBRTC_SPL_MUL_16_16_RSFT_WITH_ROUND(dfw[i].real, hnl[i], 14)); efw[i].imag = (int16_t)( WEBRTC_SPL_MUL_16_16_RSFT_WITH_ROUND(dfw[i].imag, hnl[i], 14)); } } if (aecm->cngMode == AecmTrue) { ComfortNoise(aecm, ptrDfaClean, efw, hnl); } InverseFFTAndWindow(aecm, fft, efw, output, nearendClean); return 0; } } // namespace webrtc