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
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
content / browser / speech / speech_recognizer_impl.h [blame]
// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef CONTENT_BROWSER_SPEECH_SPEECH_RECOGNIZER_IMPL_H_
#define CONTENT_BROWSER_SPEECH_SPEECH_RECOGNIZER_IMPL_H_
#include <memory>
#include <string>
#include "base/memory/raw_ptr.h"
#include "base/memory/weak_ptr.h"
#include "components/speech/endpointer/endpointer.h"
#include "components/speech/speech_recognizer_fsm.h"
#include "content/browser/speech/speech_recognition_engine.h"
#include "content/browser/speech/speech_recognizer.h"
#include "content/common/content_export.h"
#include "media/base/audio_capturer_source.h"
#include "media/mojo/mojom/audio_data.mojom.h"
#include "media/mojo/mojom/speech_recognition.mojom.h"
#include "media/mojo/mojom/speech_recognition_audio_forwarder.mojom.h"
#include "media/mojo/mojom/speech_recognition_error.mojom.h"
#include "media/mojo/mojom/speech_recognition_result.mojom.h"
#include "media/mojo/mojom/speech_recognizer.mojom.h"
#include "mojo/public/cpp/bindings/receiver.h"
namespace media {
class AudioBus;
class AudioSystem;
} // namespace media
namespace content {
class SpeechRecognitionEventListener;
struct SpeechRecognitionAudioForwarderConfig;
// Handles speech recognition for a session (identified by |session_id|), taking
// care of audio capture, silence detection/endpointer and interaction with the
// SpeechRecognitionEngine.
class CONTENT_EXPORT SpeechRecognizerImpl
: public SpeechRecognizer,
public media::AudioCapturerSource::CaptureCallback,
public SpeechRecognitionEngine::Delegate,
public speech::SpeechRecognizerFsm,
public media::mojom::SpeechRecognitionAudioForwarder {
public:
static constexpr int kAudioSampleRate = 16000;
static constexpr media::ChannelLayout kChannelLayout =
media::CHANNEL_LAYOUT_MONO;
static constexpr int kNumBitsPerAudioSample = 16;
static constexpr int kNoSpeechTimeoutMs = 8000;
static constexpr int kEndpointerEstimationTimeMs = 300;
static void SetAudioEnvironmentForTesting(
media::AudioSystem* audio_system,
media::AudioCapturerSource* capturer_source);
SpeechRecognizerImpl(SpeechRecognitionEventListener* listener,
media::AudioSystem* audio_system,
int session_id,
bool continuous,
bool provisional_results,
std::unique_ptr<SpeechRecognitionEngine> engine,
std::optional<SpeechRecognitionAudioForwarderConfig>
audio_forwarder_config);
SpeechRecognizerImpl(const SpeechRecognizerImpl&) = delete;
SpeechRecognizerImpl& operator=(const SpeechRecognizerImpl&) = delete;
// SpeechRecognizer methods.
void StartRecognition(const std::string& device_id) override;
void AbortRecognition() override;
void StopAudioCapture() override;
bool IsActive() const override;
bool IsCapturingAudio() const override;
const SpeechRecognitionEngine& recognition_engine() const;
private:
friend class SpeechRecognizerTest;
~SpeechRecognizerImpl() override;
// Callback from AudioSystem.
void OnAudioParametersReceived(
const std::optional<media::AudioParameters>& params);
// speech::SpeechRecognizerFsm implementation.
// Process a new audio chunk in the audio pipeline (endpointer, vumeter, etc).
void DispatchEvent(const FSMEventArgs& event_args) override;
void ProcessAudioPipeline(const FSMEventArgs& event_args) override;
FSMState PrepareRecognition(const FSMEventArgs&) override;
FSMState StartRecording(const FSMEventArgs& event_args) override;
FSMState StartRecognitionEngine(const FSMEventArgs& event_args) override;
FSMState WaitEnvironmentEstimationCompletion(
const FSMEventArgs& event_args) override;
FSMState DetectUserSpeechOrTimeout(const FSMEventArgs& event_args) override;
FSMState StopCaptureAndWaitForResult(const FSMEventArgs& event_args) override;
FSMState ProcessIntermediateResult(const FSMEventArgs& event_args) override;
FSMState ProcessFinalResult(const FSMEventArgs& event_args) override;
FSMState AbortSilently(const FSMEventArgs& event_args) override;
FSMState AbortWithError(const FSMEventArgs& event_args) override;
FSMState Abort(const media::mojom::SpeechRecognitionError& error) override;
FSMState DetectEndOfSpeech(const FSMEventArgs& event_args) override;
FSMState DoNothing(const FSMEventArgs& event_args) const override;
FSMState NotFeasible(const FSMEventArgs& event_args) override;
// Returns the time span of captured audio samples since the start of capture.
int GetElapsedTimeMs() const;
// Calculates the input volume to be displayed in the UI, triggering the
// OnAudioLevelsChange event accordingly.
void UpdateSignalAndNoiseLevels(const float& rms, bool clip_detected);
void CloseAudioCapturerSource();
// media::AudioCapturerSource::CaptureCallback methods.
void OnCaptureStarted() final {}
void Capture(const media::AudioBus* audio_bus,
base::TimeTicks audio_capture_time,
const media::AudioGlitchInfo& glitch_info,
double volume,
bool key_pressed) final;
void OnCaptureError(media::AudioCapturerSource::ErrorCode code,
const std::string& message) final;
void OnCaptureMuted(bool is_muted) final {}
// media::mojom::blink::SpeechRecognitionAudioForwarder methods.
void AddAudioFromRenderer(media::mojom::AudioDataS16Ptr buffer) override;
// SpeechRecognitionEngineDelegate methods.
void OnSpeechRecognitionEngineResults(
const std::vector<media::mojom::WebSpeechRecognitionResultPtr>& results)
override;
void OnSpeechRecognitionEngineEndOfUtterance() override;
void OnSpeechRecognitionEngineError(
const media::mojom::SpeechRecognitionError& error) override;
media::AudioSystem* GetAudioSystem();
void CreateAudioCapturerSource();
media::AudioCapturerSource* GetAudioCapturerSource();
// Substitute the real audio system and capturer source in browser tests.
static media::AudioSystem* audio_system_for_tests_;
static media::AudioCapturerSource* audio_capturer_source_for_tests_;
raw_ptr<media::AudioSystem, DanglingUntriaged> audio_system_;
std::unique_ptr<SpeechRecognitionEngine> recognition_engine_;
int sample_rate_;
speech::Endpointer endpointer_;
scoped_refptr<media::AudioCapturerSource> audio_capturer_source_;
int num_samples_recorded_;
float audio_level_;
bool provisional_results_;
bool end_of_utterance_;
std::string device_id_;
media::AudioParameters audio_parameters_;
bool use_audio_capturer_source_ = true;
mojo::Receiver<media::mojom::SpeechRecognitionAudioForwarder>
audio_forwarder_receiver_;
media::AudioParameters device_params_;
class OnDataConverter;
// Converts data between native input format and a WebSpeech specific
// output format.
std::unique_ptr<SpeechRecognizerImpl::OnDataConverter> audio_converter_;
base::WeakPtrFactory<SpeechRecognizerImpl> weak_ptr_factory_{this};
};
} // namespace content
#endif // CONTENT_BROWSER_SPEECH_SPEECH_RECOGNIZER_IMPL_H_