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agc_manager_direct.h (11546B)


      1 /*
      2 *  Copyright (c) 2013 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_AGC_AGC_MANAGER_DIRECT_H_
     12 #define MODULES_AUDIO_PROCESSING_AGC_AGC_MANAGER_DIRECT_H_
     13 
     14 #include <atomic>
     15 #include <cstdint>
     16 #include <memory>
     17 #include <optional>
     18 #include <vector>
     19 
     20 #include "api/array_view.h"
     21 #include "api/audio/audio_processing.h"
     22 #include "api/environment/environment.h"
     23 #include "modules/audio_processing/agc/agc.h"
     24 #include "modules/audio_processing/agc2/clipping_predictor.h"
     25 #include "modules/audio_processing/audio_buffer.h"
     26 #include "modules/audio_processing/logging/apm_data_dumper.h"
     27 #include "rtc_base/gtest_prod_util.h"
     28 
     29 namespace webrtc {
     30 
     31 class MonoAgc;
     32 class GainControl;
     33 
     34 // Adaptive Gain Controller (AGC) that controls the input volume and a digital
     35 // gain. The input volume controller recommends what volume to use, handles
     36 // volume changes and clipping. In particular, it handles changes triggered by
     37 // the user (e.g., volume set to zero by a HW mute button). The digital
     38 // controller chooses and applies the digital compression gain.
     39 // This class is not thread-safe.
     40 // TODO(bugs.webrtc.org/7494): Use applied/recommended input volume naming
     41 // convention.
     42 class AgcManagerDirect final {
     43 public:
     44  // Ctor. `num_capture_channels` specifies the number of channels for the audio
     45  // passed to `AnalyzePreProcess()` and `Process()`. Clamps
     46  // `analog_config.startup_min_level` in the [12, 255] range.
     47  AgcManagerDirect(
     48      const Environment& env,
     49      int num_capture_channels,
     50      const AudioProcessing::Config::GainController1::AnalogGainController&
     51          analog_config);
     52 
     53  ~AgcManagerDirect();
     54  AgcManagerDirect(const AgcManagerDirect&) = delete;
     55  AgcManagerDirect& operator=(const AgcManagerDirect&) = delete;
     56 
     57  void Initialize();
     58 
     59  // Configures `gain_control` to work as a fixed digital controller so that the
     60  // adaptive part is only handled by this gain controller. Must be called if
     61  // `gain_control` is also used to avoid the side-effects of running two AGCs.
     62  void SetupDigitalGainControl(GainControl& gain_control) const;
     63 
     64  // Sets the applied input volume.
     65  void set_stream_analog_level(int level);
     66 
     67  // TODO(bugs.webrtc.org/7494): Add argument for the applied input volume and
     68  // remove `set_stream_analog_level()`.
     69  // Analyzes `audio` before `Process()` is called so that the analysis can be
     70  // performed before external digital processing operations take place (e.g.,
     71  // echo cancellation). The analysis consists of input clipping detection and
     72  // prediction (if enabled). Must be called after `set_stream_analog_level()`.
     73  void AnalyzePreProcess(const AudioBuffer& audio_buffer);
     74 
     75  // Processes `audio_buffer`. Chooses a digital compression gain and the new
     76  // input volume to recommend. Must be called after `AnalyzePreProcess()`. If
     77  // `speech_probability` (range [0.0f, 1.0f]) and `speech_level_dbfs` (range
     78  // [-90.f, 30.0f]) are given, uses them to override the estimated RMS error.
     79  // TODO(webrtc:7494): This signature is needed for testing purposes, unify
     80  // the signatures when the clean-up is done.
     81  void Process(const AudioBuffer& audio_buffer,
     82               std::optional<float> speech_probability,
     83               std::optional<float> speech_level_dbfs);
     84 
     85  // Processes `audio_buffer`. Chooses a digital compression gain and the new
     86  // input volume to recommend. Must be called after `AnalyzePreProcess()`.
     87  void Process(const AudioBuffer& audio_buffer);
     88 
     89  // TODO(bugs.webrtc.org/7494): Return recommended input volume and remove
     90  // `recommended_analog_level()`.
     91  // Returns the recommended input volume. If the input volume contoller is
     92  // disabled, returns the input volume set via the latest
     93  // `set_stream_analog_level()` call. Must be called after
     94  // `AnalyzePreProcess()` and `Process()`.
     95  int recommended_analog_level() const { return recommended_input_volume_; }
     96 
     97  // Call when the capture stream output has been flagged to be used/not-used.
     98  // If unused, the manager  disregards all incoming audio.
     99  void HandleCaptureOutputUsedChange(bool capture_output_used);
    100 
    101  float voice_probability() const;
    102 
    103  int num_channels() const { return num_capture_channels_; }
    104 
    105  // If available, returns the latest digital compression gain that has been
    106  // chosen.
    107  std::optional<int> GetDigitalComressionGain();
    108 
    109  // Returns true if clipping prediction is enabled.
    110  bool clipping_predictor_enabled() const { return !!clipping_predictor_; }
    111 
    112  // Returns true if clipping prediction is used to adjust the input volume.
    113  bool use_clipping_predictor_step() const {
    114    return use_clipping_predictor_step_;
    115  }
    116 
    117 private:
    118  friend class AgcManagerDirectTestHelper;
    119 
    120  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectTest, DisableDigitalDisablesDigital);
    121  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectTest,
    122                           AgcMinMicLevelExperimentDefault);
    123  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectTest,
    124                           AgcMinMicLevelExperimentDisabled);
    125  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectTest,
    126                           AgcMinMicLevelExperimentOutOfRangeAbove);
    127  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectTest,
    128                           AgcMinMicLevelExperimentOutOfRangeBelow);
    129  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectTest,
    130                           AgcMinMicLevelExperimentEnabled50);
    131  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectTest,
    132                           AgcMinMicLevelExperimentEnabledAboveStartupLevel);
    133  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectParametrizedTest,
    134                           ClippingParametersVerified);
    135  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectParametrizedTest,
    136                           DisableClippingPredictorDoesNotLowerVolume);
    137  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectParametrizedTest,
    138                           UsedClippingPredictionsProduceLowerAnalogLevels);
    139  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectParametrizedTest,
    140                           UnusedClippingPredictionsProduceEqualAnalogLevels);
    141  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectParametrizedTest,
    142                           EmptyRmsErrorOverrideHasNoEffect);
    143  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectParametrizedTest,
    144                           NonEmptyRmsErrorOverrideHasEffect);
    145 
    146  // Ctor that creates a single channel AGC and by injecting `agc`.
    147  // `agc` will be owned by this class; hence, do not delete it.
    148  AgcManagerDirect(
    149      const Environment& env,
    150      const AudioProcessing::Config::GainController1::AnalogGainController&
    151          analog_config,
    152      Agc* agc);
    153 
    154  void AggregateChannelLevels();
    155 
    156  const bool analog_controller_enabled_;
    157 
    158  const std::optional<int> min_mic_level_override_;
    159  std::unique_ptr<ApmDataDumper> data_dumper_;
    160  static std::atomic<int> instance_counter_;
    161  const int num_capture_channels_;
    162  const bool disable_digital_adaptive_;
    163 
    164  int frames_since_clipped_;
    165 
    166  // TODO(bugs.webrtc.org/7494): Create a separate member for the applied input
    167  // volume.
    168  // TODO(bugs.webrtc.org/7494): Once
    169  // `AudioProcessingImpl::recommended_stream_analog_level()` becomes a trivial
    170  // getter, leave uninitialized.
    171  // Recommended input volume. After `set_stream_analog_level()` is called it
    172  // holds the observed input volume. Possibly updated by `AnalyzePreProcess()`
    173  // and `Process()`; after these calls, holds the recommended input volume.
    174  int recommended_input_volume_ = 0;
    175 
    176  bool capture_output_used_;
    177  int channel_controlling_gain_ = 0;
    178 
    179  const int clipped_level_step_;
    180  const float clipped_ratio_threshold_;
    181  const int clipped_wait_frames_;
    182 
    183  std::vector<std::unique_ptr<MonoAgc>> channel_agcs_;
    184  std::vector<std::optional<int>> new_compressions_to_set_;
    185 
    186  const std::unique_ptr<ClippingPredictor> clipping_predictor_;
    187  const bool use_clipping_predictor_step_;
    188  float clipping_rate_log_;
    189  int clipping_rate_log_counter_;
    190 };
    191 
    192 // TODO(bugs.webrtc.org/7494): Use applied/recommended input volume naming
    193 // convention.
    194 class MonoAgc {
    195 public:
    196  MonoAgc(ApmDataDumper* data_dumper,
    197          int clipped_level_min,
    198          bool disable_digital_adaptive,
    199          int min_mic_level);
    200  ~MonoAgc();
    201  MonoAgc(const MonoAgc&) = delete;
    202  MonoAgc& operator=(const MonoAgc&) = delete;
    203 
    204  void Initialize();
    205  void HandleCaptureOutputUsedChange(bool capture_output_used);
    206 
    207  // Sets the current input volume.
    208  void set_stream_analog_level(int level) { recommended_input_volume_ = level; }
    209 
    210  // Lowers the recommended input volume in response to clipping based on the
    211  // suggested reduction `clipped_level_step`. Must be called after
    212  // `set_stream_analog_level()`.
    213  void HandleClipping(int clipped_level_step);
    214 
    215  // Analyzes `audio`, requests the RMS error from AGC, updates the recommended
    216  // input volume based on the estimated speech level and, if enabled, updates
    217  // the (digital) compression gain to be applied by `agc_`. Must be called
    218  // after `HandleClipping()`. If `rms_error_override` has a value, RMS error
    219  // from AGC is overridden by it.
    220  void Process(ArrayView<const int16_t> audio,
    221               std::optional<int> rms_error_override);
    222 
    223  // Returns the recommended input volume. Must be called after `Process()`.
    224  int recommended_analog_level() const { return recommended_input_volume_; }
    225 
    226  float voice_probability() const { return agc_->voice_probability(); }
    227  void ActivateLogging() { log_to_histograms_ = true; }
    228  std::optional<int> new_compression() const { return new_compression_to_set_; }
    229 
    230  // Only used for testing.
    231  void set_agc(Agc* agc) { agc_.reset(agc); }
    232  int min_mic_level() const { return min_mic_level_; }
    233 
    234 private:
    235  // Sets a new input volume, after first checking that it hasn't been updated
    236  // by the user, in which case no action is taken.
    237  void SetLevel(int new_level);
    238 
    239  // Set the maximum input volume the AGC is allowed to apply. Also updates the
    240  // maximum compression gain to compensate. The volume must be at least
    241  // `kClippedLevelMin`.
    242  void SetMaxLevel(int level);
    243 
    244  int CheckVolumeAndReset();
    245  void UpdateGain(int rms_error_db);
    246  void UpdateCompressor();
    247 
    248  const int min_mic_level_;
    249  const bool disable_digital_adaptive_;
    250  std::unique_ptr<Agc> agc_;
    251  int level_ = 0;
    252  int max_level_;
    253  int max_compression_gain_;
    254  int target_compression_;
    255  int compression_;
    256  float compression_accumulator_;
    257  bool capture_output_used_ = true;
    258  bool check_volume_on_next_process_ = true;
    259  bool startup_ = true;
    260 
    261  // TODO(bugs.webrtc.org/7494): Create a separate member for the applied
    262  // input volume.
    263  // Recommended input volume. After `set_stream_analog_level()` is
    264  // called, it holds the observed applied input volume. Possibly updated by
    265  // `HandleClipping()` and `Process()`; after these calls, holds the
    266  // recommended input volume.
    267  int recommended_input_volume_ = 0;
    268 
    269  std::optional<int> new_compression_to_set_;
    270  bool log_to_histograms_ = false;
    271  const int clipped_level_min_;
    272 
    273  // Frames since the last `UpdateGain()` call.
    274  int frames_since_update_gain_ = 0;
    275  // Set to true for the first frame after startup and reset, otherwise false.
    276  bool is_first_frame_ = true;
    277 };
    278 
    279 }  // namespace webrtc
    280 
    281 #endif  // MODULES_AUDIO_PROCESSING_AGC_AGC_MANAGER_DIRECT_H_