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gain_controller2.h (4697B)

      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_GAIN_CONTROLLER2_H_
     12 #define MODULES_AUDIO_PROCESSING_GAIN_CONTROLLER2_H_
     13 
     14 #include <atomic>
     15 #include <memory>
     16 #include <optional>
     17 
     18 #include "api/audio/audio_processing.h"
     19 #include "api/environment/environment.h"
     20 #include "modules/audio_processing/agc2/adaptive_digital_gain_controller.h"
     21 #include "modules/audio_processing/agc2/cpu_features.h"
     22 #include "modules/audio_processing/agc2/gain_applier.h"
     23 #include "modules/audio_processing/agc2/input_volume_controller.h"
     24 #include "modules/audio_processing/agc2/limiter.h"
     25 #include "modules/audio_processing/agc2/noise_level_estimator.h"
     26 #include "modules/audio_processing/agc2/saturation_protector.h"
     27 #include "modules/audio_processing/agc2/speech_level_estimator.h"
     28 #include "modules/audio_processing/agc2/vad_wrapper.h"
     29 #include "modules/audio_processing/logging/apm_data_dumper.h"
     30 
     31 namespace webrtc {
     32 
     33 class AudioBuffer;
     34 
     35 // Gain Controller 2 aims to automatically adjust levels by acting on the
     36 // microphone gain and/or applying digital gain.
     37 class GainController2 {
     38 public:
     39  // Ctor. If `use_internal_vad` is true, an internal voice activity
     40  // detector is used for digital adaptive gain.
     41  GainController2(
     42      const Environment& env,
     43      const AudioProcessing::Config::GainController2& config,
     44      const InputVolumeController::Config& input_volume_controller_config,
     45      int sample_rate_hz,
     46      int num_channels,
     47      bool use_internal_vad);
     48  GainController2(const GainController2&) = delete;
     49  GainController2& operator=(const GainController2&) = delete;
     50  ~GainController2();
     51 
     52  // Sets the fixed digital gain.
     53  void SetFixedGainDb(float gain_db);
     54 
     55  // Updates the input volume controller about whether the capture output is
     56  // used or not.
     57  void SetCaptureOutputUsed(bool capture_output_used);
     58 
     59  // Analyzes `audio_buffer` before `Process()` is called so that the analysis
     60  // can be performed before digital processing operations take place (e.g.,
     61  // echo cancellation). The analysis consists of input clipping detection and
     62  // prediction (if enabled). The value of `applied_input_volume` is limited to
     63  // [0, 255].
     64  void Analyze(int applied_input_volume, const AudioBuffer& audio_buffer);
     65 
     66  // Updates the recommended input volume, applies the adaptive digital and the
     67  // fixed digital gains and runs a limiter on `audio`.
     68  // When the internal VAD is not used, `speech_probability` should be specified
     69  // and in the [0, 1] range. Otherwise ignores `speech_probability` and
     70  // computes the speech probability via `vad_`.
     71  // Handles input volume changes; if the caller cannot determine whether an
     72  // input volume change occurred, set `input_volume_changed` to false.
     73  // TODO(bugs.webrtc.org/7494): Remove `speech_probability`.
     74  void Process(std::optional<float> speech_probability,
     75               bool input_volume_changed,
     76               AudioBuffer* audio);
     77 
     78  static bool Validate(const AudioProcessing::Config::GainController2& config);
     79 
     80  AvailableCpuFeatures GetCpuFeatures() const { return cpu_features_; }
     81 
     82  std::optional<int> recommended_input_volume() const {
     83    return recommended_input_volume_;
     84  }
     85 
     86 private:
     87  static std::atomic<int> instance_count_;
     88  const AvailableCpuFeatures cpu_features_;
     89  ApmDataDumper data_dumper_;
     90 
     91  GainApplier fixed_gain_applier_;
     92  std::unique_ptr<NoiseLevelEstimator> noise_level_estimator_;
     93  std::unique_ptr<VoiceActivityDetectorWrapper> vad_;
     94  std::unique_ptr<SpeechLevelEstimator> speech_level_estimator_;
     95  std::unique_ptr<InputVolumeController> input_volume_controller_;
     96  // TODO(bugs.webrtc.org/7494): Rename to `CrestFactorEstimator`.
     97  std::unique_ptr<SaturationProtector> saturation_protector_;
     98  std::unique_ptr<AdaptiveDigitalGainController> adaptive_digital_controller_;
     99  Limiter limiter_;
    100 
    101  int calls_since_last_limiter_log_;
    102 
    103  // TODO(bugs.webrtc.org/7494): Remove intermediate storing at this level once
    104  // APM refactoring is completed.
    105  // Recommended input volume from `InputVolumecontroller`. Non-empty after
    106  // `Process()` if input volume controller is enabled and
    107  // `InputVolumeController::Process()` has returned a non-empty value.
    108  std::optional<int> recommended_input_volume_;
    109 };
    110 
    111 }  // namespace webrtc
    112 
    113 #endif  // MODULES_AUDIO_PROCESSING_GAIN_CONTROLLER2_H_