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 MODULES_AUDIO_PROCESSING_AGC2_DOWN_SAMPLER_H_
12 #define MODULES_AUDIO_PROCESSING_AGC2_DOWN_SAMPLER_H_
13 
14 #include "api/array_view.h"
15 #include "modules/audio_processing/agc2/biquad_filter.h"
16 #include "rtc_base/constructor_magic.h"
17 
18 namespace webrtc {
19 
20 class ApmDataDumper;
21 
22 class DownSampler {
23  public:
24   explicit DownSampler(ApmDataDumper* data_dumper);
25   void Initialize(int sample_rate_hz);
26 
27   void DownSample(rtc::ArrayView<const float> in, rtc::ArrayView<float> out);
28 
29  private:
30   ApmDataDumper* data_dumper_;
31   int sample_rate_hz_;
32   int down_sampling_factor_;
33   BiQuadFilter low_pass_filter_;
34 
35   RTC_DISALLOW_IMPLICIT_CONSTRUCTORS(DownSampler);
36 };
37 
38 }  // namespace webrtc
39 
40 #endif  // MODULES_AUDIO_PROCESSING_AGC2_DOWN_SAMPLER_H_
41