1 /* 2 * Copyright (c) 2018 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_ECHO_AUDIBILITY_H_ 12 #define MODULES_AUDIO_PROCESSING_AEC3_ECHO_AUDIBILITY_H_ 13 14 #include <stddef.h> 15 16 #include "absl/types/optional.h" 17 #include "api/array_view.h" 18 #include "modules/audio_processing/aec3/block_buffer.h" 19 #include "modules/audio_processing/aec3/render_buffer.h" 20 #include "modules/audio_processing/aec3/spectrum_buffer.h" 21 #include "modules/audio_processing/aec3/stationarity_estimator.h" 22 23 namespace webrtc { 24 25 class EchoAudibility { 26 public: 27 explicit EchoAudibility(bool use_render_stationarity_at_init); 28 ~EchoAudibility(); 29 30 EchoAudibility(const EchoAudibility&) = delete; 31 EchoAudibility& operator=(const EchoAudibility&) = delete; 32 33 // Feed new render data to the echo audibility estimator. 34 void Update(const RenderBuffer& render_buffer, 35 rtc::ArrayView<const float> average_reverb, 36 int min_channel_delay_blocks, 37 bool external_delay_seen); 38 // Get the residual echo scaling. GetResidualEchoScaling(bool filter_has_had_time_to_converge,rtc::ArrayView<float> residual_scaling)39 void GetResidualEchoScaling(bool filter_has_had_time_to_converge, 40 rtc::ArrayView<float> residual_scaling) const { 41 for (size_t band = 0; band < residual_scaling.size(); ++band) { 42 if (render_stationarity_.IsBandStationary(band) && 43 (filter_has_had_time_to_converge || 44 use_render_stationarity_at_init_)) { 45 residual_scaling[band] = 0.f; 46 } else { 47 residual_scaling[band] = 1.0f; 48 } 49 } 50 } 51 52 // Returns true if the current render block is estimated as stationary. IsBlockStationary()53 bool IsBlockStationary() const { 54 return render_stationarity_.IsBlockStationary(); 55 } 56 57 private: 58 // Reset the EchoAudibility class. 59 void Reset(); 60 61 // Updates the render stationarity flags for the current frame. 62 void UpdateRenderStationarityFlags(const RenderBuffer& render_buffer, 63 rtc::ArrayView<const float> average_reverb, 64 int delay_blocks); 65 66 // Updates the noise estimator with the new render data since the previous 67 // call to this method. 68 void UpdateRenderNoiseEstimator(const SpectrumBuffer& spectrum_buffer, 69 const BlockBuffer& block_buffer, 70 bool external_delay_seen); 71 72 // Returns a bool being true if the render signal contains just close to zero 73 // values. 74 bool IsRenderTooLow(const BlockBuffer& block_buffer); 75 76 absl::optional<int> render_spectrum_write_prev_; 77 int render_block_write_prev_; 78 bool non_zero_render_seen_; 79 const bool use_render_stationarity_at_init_; 80 StationarityEstimator render_stationarity_; 81 }; 82 83 } // namespace webrtc 84 85 #endif // MODULES_AUDIO_PROCESSING_AEC3_ECHO_AUDIBILITY_H_ 86