1 /*
2  *  Copyright (c) 2016 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 WEBRTC_MODULES_AUDIO_PROCESSING_LEVEL_CONTROLLER_GAIN_APPLIER_H_
12 #define WEBRTC_MODULES_AUDIO_PROCESSING_LEVEL_CONTROLLER_GAIN_APPLIER_H_
13 
14 #include "webrtc/base/constructormagic.h"
15 
16 namespace webrtc {
17 
18 class ApmDataDumper;
19 class AudioBuffer;
20 
21 class GainApplier {
22  public:
23   explicit GainApplier(ApmDataDumper* data_dumper);
24   void Initialize(int sample_rate_hz);
25 
26   // Applies the specified gain to the audio frame and returns the resulting
27   // number of saturated sample values.
28   int Process(float new_gain, AudioBuffer* audio);
29 
30  private:
31   ApmDataDumper* const data_dumper_;
32   float old_gain_ = 1.f;
33   float gain_increase_step_size_ = 0.f;
34   float gain_normal_decrease_step_size_ = 0.f;
35   float gain_saturated_decrease_step_size_ = 0.f;
36   bool last_frame_was_saturated_;
37   RTC_DISALLOW_IMPLICIT_CONSTRUCTORS(GainApplier);
38 };
39 
40 }  // namespace webrtc
41 
42 #endif  // WEBRTC_MODULES_AUDIO_PROCESSING_LEVEL_CONTROLLER_GAIN_APPLIER_H_
43