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
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
|
/*
* Copyright (c) 2013 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 WEBRTC_MODULES_AUDIO_PROCESSING_TRANSIENT_TRANSIENT_SUPPRESSOR_H_
#define WEBRTC_MODULES_AUDIO_PROCESSING_TRANSIENT_TRANSIENT_SUPPRESSOR_H_
#include <deque>
#include <set>
#include "webrtc/system_wrappers/interface/scoped_ptr.h"
#include "webrtc/test/testsupport/gtest_prod_util.h"
#include "webrtc/typedefs.h"
namespace webrtc {
class TransientDetector;
// Detects transients in an audio stream and suppress them using a simple
// restoration algorithm that attenuates unexpected spikes in the spectrum.
class TransientSuppressor {
public:
TransientSuppressor();
~TransientSuppressor();
int Initialize(int sample_rate_hz, int detector_rate_hz, int num_channels);
// Processes a |data| chunk, and returns it with keystrokes suppressed from
// it. The float format is assumed to be int16 ranged. If there are more than
// one channel, the chunks are concatenated one after the other in |data|.
// |data_length| must be equal to |data_length_|.
// |num_channels| must be equal to |num_channels_|.
// A sub-band, ideally the higher, can be used as |detection_data|. If it is
// NULL, |data| is used for the detection too. The |detection_data| is always
// assumed mono.
// If a reference signal (e.g. keyboard microphone) is available, it can be
// passed in as |reference_data|. It is assumed mono and must have the same
// length as |data|. NULL is accepted if unavailable.
// This suppressor performs better if voice information is available.
// |voice_probability| is the probability of voice being present in this chunk
// of audio. If voice information is not available, |voice_probability| must
// always be set to 1.
// |key_pressed| determines if a key was pressed on this audio chunk.
// Returns 0 on success and -1 otherwise.
int Suppress(float* data,
size_t data_length,
int num_channels,
const float* detection_data,
size_t detection_length,
const float* reference_data,
size_t reference_length,
float voice_probability,
bool key_pressed);
private:
FRIEND_TEST_ALL_PREFIXES(TransientSuppressorTest,
TypingDetectionLogicWorksAsExpectedForMono);
void Suppress(float* in_ptr, float* spectral_mean, float* out_ptr);
void UpdateKeypress(bool key_pressed);
void UpdateRestoration(float voice_probability);
void UpdateBuffers(float* data);
void HardRestoration(float* spectral_mean);
void SoftRestoration(float* spectral_mean);
scoped_ptr<TransientDetector> detector_;
size_t data_length_;
size_t detection_length_;
size_t analysis_length_;
size_t buffer_delay_;
size_t complex_analysis_length_;
int num_channels_;
// Input buffer where the original samples are stored.
scoped_ptr<float[]> in_buffer_;
scoped_ptr<float[]> detection_buffer_;
// Output buffer where the restored samples are stored.
scoped_ptr<float[]> out_buffer_;
// Arrays for fft.
scoped_ptr<int[]> ip_;
scoped_ptr<float[]> wfft_;
scoped_ptr<float[]> spectral_mean_;
// Stores the data for the fft.
scoped_ptr<float[]> fft_buffer_;
scoped_ptr<float[]> magnitudes_;
const float* window_;
scoped_ptr<float[]> mean_factor_;
float detector_smoothed_;
int keypress_counter_;
int chunks_since_keypress_;
bool detection_enabled_;
bool suppression_enabled_;
bool use_hard_restoration_;
int chunks_since_voice_change_;
uint32_t seed_;
bool using_reference_;
};
} // namespace webrtc
#endif // WEBRTC_MODULES_AUDIO_PROCESSING_TRANSIENT_TRANSIENT_SUPPRESSOR_H_
|
