blob: 51b38714c2836e4b493229492e2ee85c692a3303 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
|
/*
* Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef MODULES_AUDIO_PROCESSING_AGC_LOUDNESS_HISTOGRAM_H_
#define MODULES_AUDIO_PROCESSING_AGC_LOUDNESS_HISTOGRAM_H_
#include <stdint.h>
#include <memory>
namespace webrtc {
// This class implements the histogram of loudness with circular buffers so that
// the histogram tracks the last T seconds of the loudness.
class LoudnessHistogram {
public:
// Create a non-sliding LoudnessHistogram.
static LoudnessHistogram* Create();
// Create a sliding LoudnessHistogram, i.e. the histogram represents the last
// `window_size` samples.
static LoudnessHistogram* Create(int window_size);
~LoudnessHistogram();
// Insert RMS and the corresponding activity probability.
void Update(double rms, double activity_probability);
// Reset the histogram, forget the past.
void Reset();
// Current loudness, which is actually the mean of histogram in loudness
// domain.
double CurrentRms() const;
// Sum of the histogram content.
double AudioContent() const;
// Number of times the histogram has been updated.
int num_updates() const { return num_updates_; }
private:
LoudnessHistogram();
explicit LoudnessHistogram(int window);
// Find the histogram bin associated with the given `rms`.
int GetBinIndex(double rms);
void RemoveOldestEntryAndUpdate();
void InsertNewestEntryAndUpdate(int activity_prob_q10, int hist_index);
void UpdateHist(int activity_prob_q10, int hist_index);
void RemoveTransient();
// Number of histogram bins.
static const int kHistSize = 77;
// Number of times the histogram is updated
int num_updates_;
// Audio content, this should be equal to the sum of the components of
// `bin_count_q10_`.
int64_t audio_content_q10_;
// LoudnessHistogram of input RMS in Q10 with `kHistSize_` bins. In each
// 'Update(),' we increment the associated histogram-bin with the given
// probability. The increment is implemented in Q10 to avoid rounding errors.
int64_t bin_count_q10_[kHistSize];
// Circular buffer for probabilities
std::unique_ptr<int[]> activity_probability_;
// Circular buffer for histogram-indices of probabilities.
std::unique_ptr<int[]> hist_bin_index_;
// Current index of circular buffer, where the newest data will be written to,
// therefore, pointing to the oldest data if buffer is full.
int buffer_index_;
// Indicating if buffer is full and we had a wrap around.
int buffer_is_full_;
// Size of circular buffer.
int len_circular_buffer_;
int len_high_activity_;
};
} // namespace webrtc
#endif // MODULES_AUDIO_PROCESSING_AGC_LOUDNESS_HISTOGRAM_H_
|
