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 #include "rtc_base/constructor_magic.h" 23 24 namespace webrtc { 25 26 class EchoAudibility { 27 public: 28 explicit EchoAudibility(bool use_render_stationarity_at_init); 29 ~EchoAudibility(); 30 31 EchoAudibility(const EchoAudibility&) = delete; 32 EchoAudibility& operator=(const EchoAudibility&) = delete; 33 34 // Feed new render data to the echo audibility estimator. 35 void Update(const RenderBuffer& render_buffer, 36 rtc::ArrayView<const float> average_reverb, 37 int min_channel_delay_blocks, 38 bool external_delay_seen); 39 // Get the residual echo scaling. GetResidualEchoScaling(bool filter_has_had_time_to_converge,rtc::ArrayView<float> residual_scaling)40 void GetResidualEchoScaling(bool filter_has_had_time_to_converge, 41 rtc::ArrayView<float> residual_scaling) const { 42 for (size_t band = 0; band < residual_scaling.size(); ++band) { 43 if (render_stationarity_.IsBandStationary(band) && 44 (filter_has_had_time_to_converge || 45 use_render_stationarity_at_init_)) { 46 residual_scaling[band] = 0.f; 47 } else { 48 residual_scaling[band] = 1.0f; 49 } 50 } 51 } 52 53 // Returns true if the current render block is estimated as stationary. IsBlockStationary()54 bool IsBlockStationary() const { 55 return render_stationarity_.IsBlockStationary(); 56 } 57 58 private: 59 // Reset the EchoAudibility class. 60 void Reset(); 61 62 // Updates the render stationarity flags for the current frame. 63 void UpdateRenderStationarityFlags(const RenderBuffer& render_buffer, 64 rtc::ArrayView<const float> average_reverb, 65 int delay_blocks); 66 67 // Updates the noise estimator with the new render data since the previous 68 // call to this method. 69 void UpdateRenderNoiseEstimator(const SpectrumBuffer& spectrum_buffer, 70 const BlockBuffer& block_buffer, 71 bool external_delay_seen); 72 73 // Returns a bool being true if the render signal contains just close to zero 74 // values. 75 bool IsRenderTooLow(const BlockBuffer& block_buffer); 76 77 absl::optional<int> render_spectrum_write_prev_; 78 int render_block_write_prev_; 79 bool non_zero_render_seen_; 80 const bool use_render_stationarity_at_init_; 81 StationarityEstimator render_stationarity_; 82 }; 83 84 } // namespace webrtc 85 86 #endif // MODULES_AUDIO_PROCESSING_AEC3_ECHO_AUDIBILITY_H_ 87