1 /* 2 * Copyright (c) 2017 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 #ifndef MODULES_AUDIO_PROCESSING_AEC3_ERL_ESTIMATOR_H_ 12 #define MODULES_AUDIO_PROCESSING_AEC3_ERL_ESTIMATOR_H_ 13 14 #include <array> 15 16 #include "modules/audio_processing/aec3/aec3_common.h" 17 #include "rtc_base/constructormagic.h" 18 19 namespace webrtc { 20 21 // Estimates the echo return loss based on the signal spectra. 22 class ErlEstimator { 23 public: 24 ErlEstimator(); 25 ~ErlEstimator(); 26 27 // Updates the ERL estimate. 28 void Update(const std::array<float, kFftLengthBy2Plus1>& render_spectrum, 29 const std::array<float, kFftLengthBy2Plus1>& capture_spectrum); 30 31 // Returns the most recent ERL estimate. Erl()32 const std::array<float, kFftLengthBy2Plus1>& Erl() const { return erl_; } ErlTimeDomain()33 float ErlTimeDomain() const { return erl_time_domain_; } 34 35 private: 36 std::array<float, kFftLengthBy2Plus1> erl_; 37 std::array<int, kFftLengthBy2Minus1> hold_counters_; 38 float erl_time_domain_; 39 int hold_counter_time_domain_; 40 41 RTC_DISALLOW_COPY_AND_ASSIGN(ErlEstimator); 42 }; 43 44 } // namespace webrtc 45 46 #endif // MODULES_AUDIO_PROCESSING_AEC3_ERL_ESTIMATOR_H_ 47