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_AEC3_RENDER_SIGNAL_ANALYZER_H_
12 #define MODULES_AUDIO_PROCESSING_AEC3_RENDER_SIGNAL_ANALYZER_H_
13 
14 #include <algorithm>
15 #include <array>
16 #include <cstddef>
17 
18 #include "absl/types/optional.h"
19 #include "api/audio/echo_canceller3_config.h"
20 #include "modules/audio_processing/aec3/aec3_common.h"
21 #include "modules/audio_processing/aec3/render_buffer.h"
22 #include "rtc_base/checks.h"
23 #include "rtc_base/constructor_magic.h"
24 
25 namespace webrtc {
26 
27 // Provides functionality for analyzing the properties of the render signal.
28 class RenderSignalAnalyzer {
29  public:
30   explicit RenderSignalAnalyzer(const EchoCanceller3Config& config);
31   ~RenderSignalAnalyzer();
32 
33   // Updates the render signal analysis with the most recent render signal.
34   void Update(const RenderBuffer& render_buffer,
35               const absl::optional<size_t>& delay_partitions);
36 
37   // Returns true if the render signal is poorly exciting.
PoorSignalExcitation()38   bool PoorSignalExcitation() const {
39     RTC_DCHECK_LT(2, narrow_band_counters_.size());
40     return std::any_of(narrow_band_counters_.begin(),
41                        narrow_band_counters_.end(),
42                        [](size_t a) { return a > 10; });
43   }
44 
45   // Zeros the array around regions with narrow bands signal characteristics.
46   void MaskRegionsAroundNarrowBands(
47       std::array<float, kFftLengthBy2Plus1>* v) const;
48 
NarrowPeakBand()49   absl::optional<int> NarrowPeakBand() const { return narrow_peak_band_; }
50 
51  private:
52   const int strong_peak_freeze_duration_;
53   std::array<size_t, kFftLengthBy2 - 1> narrow_band_counters_;
54   absl::optional<int> narrow_peak_band_;
55   size_t narrow_peak_counter_;
56 
57   RTC_DISALLOW_COPY_AND_ASSIGN(RenderSignalAnalyzer);
58 };
59 
60 }  // namespace webrtc
61 
62 #endif  // MODULES_AUDIO_PROCESSING_AEC3_RENDER_SIGNAL_ANALYZER_H_
63