xref: /aosp_15_r20/external/webrtc/modules/audio_processing/agc2/saturation_protector.h (revision d9f758449e529ab9291ac668be2861e7a55c2422)
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_AGC2_SATURATION_PROTECTOR_H_
12 #define MODULES_AUDIO_PROCESSING_AGC2_SATURATION_PROTECTOR_H_
13 
14 #include <memory>
15 
16 namespace webrtc {
17 class ApmDataDumper;
18 
19 // Saturation protector. Analyzes peak levels and recommends a headroom to
20 // reduce the chances of clipping.
21 class SaturationProtector {
22  public:
23   virtual ~SaturationProtector() = default;
24 
25   // Returns the recommended headroom in dB.
26   virtual float HeadroomDb() = 0;
27 
28   // Analyzes the peak level of a 10 ms frame along with its speech probability
29   // and the current speech level estimate to update the recommended headroom.
30   virtual void Analyze(float speech_probability,
31                        float peak_dbfs,
32                        float speech_level_dbfs) = 0;
33 
34   // Resets the internal state.
35   virtual void Reset() = 0;
36 };
37 
38 // Creates a saturation protector that starts at `initial_headroom_db`.
39 std::unique_ptr<SaturationProtector> CreateSaturationProtector(
40     float initial_headroom_db,
41     int adjacent_speech_frames_threshold,
42     ApmDataDumper* apm_data_dumper);
43 
44 }  // namespace webrtc
45 
46 #endif  // MODULES_AUDIO_PROCESSING_AGC2_SATURATION_PROTECTOR_H_
47