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
|
/*
* 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 WEBRTC_MODULES_AUDIO_CODING_NETEQ_PREEMPTIVE_EXPAND_H_
#define WEBRTC_MODULES_AUDIO_CODING_NETEQ_PREEMPTIVE_EXPAND_H_
#include <assert.h>
#include "webrtc/base/constructormagic.h"
#include "webrtc/modules/audio_coding/neteq/audio_multi_vector.h"
#include "webrtc/modules/audio_coding/neteq/time_stretch.h"
#include "webrtc/typedefs.h"
namespace webrtc {
// Forward declarations.
class BackgroundNoise;
// This class implements the PreemptiveExpand operation. Most of the work is
// done in the base class TimeStretch, which is shared with the Accelerate
// operation. In the PreemptiveExpand class, the operations that are specific to
// PreemptiveExpand are implemented.
class PreemptiveExpand : public TimeStretch {
public:
PreemptiveExpand(int sample_rate_hz,
size_t num_channels,
const BackgroundNoise& background_noise,
int overlap_samples)
: TimeStretch(sample_rate_hz, num_channels, background_noise),
old_data_length_per_channel_(-1),
overlap_samples_(overlap_samples) {
}
virtual ~PreemptiveExpand() {}
// This method performs the actual PreemptiveExpand operation. The samples are
// read from |input|, of length |input_length| elements, and are written to
// |output|. The number of samples added through time-stretching is
// is provided in the output |length_change_samples|. The method returns
// the outcome of the operation as an enumerator value.
ReturnCodes Process(const int16_t *pw16_decoded,
int len,
int old_data_len,
AudioMultiVector* output,
int16_t* length_change_samples);
protected:
// Sets the parameters |best_correlation| and |peak_index| to suitable
// values when the signal contains no active speech.
virtual void SetParametersForPassiveSpeech(size_t len,
int16_t* w16_bestCorr,
int* w16_bestIndex) const;
// Checks the criteria for performing the time-stretching operation and,
// if possible, performs the time-stretching.
virtual ReturnCodes CheckCriteriaAndStretch(
const int16_t *pw16_decoded, size_t len, size_t w16_bestIndex,
int16_t w16_bestCorr, bool w16_VAD,
AudioMultiVector* output) const;
private:
int old_data_length_per_channel_;
int overlap_samples_;
DISALLOW_COPY_AND_ASSIGN(PreemptiveExpand);
};
struct PreemptiveExpandFactory {
PreemptiveExpandFactory() {}
virtual ~PreemptiveExpandFactory() {}
virtual PreemptiveExpand* Create(
int sample_rate_hz,
size_t num_channels,
const BackgroundNoise& background_noise,
int overlap_samples) const;
};
} // namespace webrtc
#endif // WEBRTC_MODULES_AUDIO_CODING_NETEQ_PREEMPTIVE_EXPAND_H_
|
