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
|
/*
* 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_CODING_NETEQ_DTMF_TONE_GENERATOR_H_
#define MODULES_AUDIO_CODING_NETEQ_DTMF_TONE_GENERATOR_H_
#include <stddef.h>
#include <stdint.h>
#include "modules/audio_coding/neteq/audio_multi_vector.h"
namespace webrtc {
// This class provides a generator for DTMF tones.
class DtmfToneGenerator {
public:
enum ReturnCodes {
kNotInitialized = -1,
kParameterError = -2,
};
DtmfToneGenerator();
virtual ~DtmfToneGenerator() {}
DtmfToneGenerator(const DtmfToneGenerator&) = delete;
DtmfToneGenerator& operator=(const DtmfToneGenerator&) = delete;
virtual int Init(int fs, int event, int attenuation);
virtual void Reset();
virtual int Generate(size_t num_samples, AudioMultiVector* output);
virtual bool initialized() const;
private:
static const int kCoeff1[4][16]; // 1st oscillator model coefficient table.
static const int kCoeff2[4][16]; // 2nd oscillator model coefficient table.
static const int kInitValue1[4][16]; // Initialization for 1st oscillator.
static const int kInitValue2[4][16]; // Initialization for 2nd oscillator.
static const int kAmplitude[64]; // Amplitude for 0 through -63 dBm0.
static const int16_t kAmpMultiplier = 23171; // 3 dB attenuation (in Q15).
bool initialized_; // True if generator is initialized properly.
int coeff1_; // 1st oscillator coefficient for this event.
int coeff2_; // 2nd oscillator coefficient for this event.
int amplitude_; // Amplitude for this event.
int16_t sample_history1_[2]; // Last 2 samples for the 1st oscillator.
int16_t sample_history2_[2]; // Last 2 samples for the 2nd oscillator.
};
} // namespace webrtc
#endif // MODULES_AUDIO_CODING_NETEQ_DTMF_TONE_GENERATOR_H_
|
