1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef MEDIA_AUDIO_AUDIO_INPUT_CONTROLLER_H_ 6 #define MEDIA_AUDIO_AUDIO_INPUT_CONTROLLER_H_ 7 8 #include <string> 9 #include "base/atomicops.h" 10 #include "base/callback.h" 11 #include "base/memory/ref_counted.h" 12 #include "base/memory/scoped_ptr.h" 13 #include "base/synchronization/lock.h" 14 #include "base/synchronization/waitable_event.h" 15 #include "base/threading/thread.h" 16 #include "base/timer/timer.h" 17 #include "media/audio/audio_io.h" 18 #include "media/audio/audio_manager_base.h" 19 #include "media/audio/audio_parameters.h" 20 #include "media/audio/audio_power_monitor.h" 21 #include "media/base/audio_bus.h" 22 23 // An AudioInputController controls an AudioInputStream and records data 24 // from this input stream. The two main methods are Record() and Close() and 25 // they are both executed on the audio thread which is injected by the two 26 // alternative factory methods, Create() or CreateLowLatency(). 27 // 28 // All public methods of AudioInputController are non-blocking. 29 // 30 // Here is a state diagram for the AudioInputController: 31 // 32 // .--> [ Closed / Error ] <--. 33 // | | 34 // | | 35 // [ Created ] ----------> [ Recording ] 36 // ^ 37 // | 38 // *[ Empty ] 39 // 40 // * Initial state 41 // 42 // State sequences (assuming low-latency): 43 // 44 // [Creating Thread] [Audio Thread] 45 // 46 // User AudioInputController EventHandler 47 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 48 // CrateLowLatency() ==> DoCreate() 49 // AudioManager::MakeAudioInputStream() 50 // AudioInputStream::Open() 51 // .- - - - - - - - - - - - -> OnError() 52 // create the data timer 53 // .-------------------------> OnCreated() 54 // kCreated 55 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 56 // Record() ==> DoRecord() 57 // AudioInputStream::Start() 58 // .-------------------------> OnRecording() 59 // start the data timer 60 // kRecording 61 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 62 // Close() ==> DoClose() 63 // delete the data timer 64 // state_ = kClosed 65 // AudioInputStream::Stop() 66 // AudioInputStream::Close() 67 // SyncWriter::Close() 68 // Closure::Run() <-----------------. 69 // (closure-task) 70 // 71 // The audio thread itself is owned by the AudioManager that the 72 // AudioInputController holds a reference to. When performing tasks on the 73 // audio thread, the controller must not add or release references to the 74 // AudioManager or itself (since it in turn holds a reference to the manager). 75 // 76 namespace media { 77 78 // Only do power monitoring for non-mobile platforms to save resources. 79 #if !defined(OS_ANDROID) && !defined(OS_IOS) 80 #define AUDIO_POWER_MONITORING 81 #endif 82 83 class UserInputMonitor; 84 85 class MEDIA_EXPORT AudioInputController 86 : public base::RefCountedThreadSafe<AudioInputController>, 87 public AudioInputStream::AudioInputCallback { 88 public: 89 90 // Error codes to make native loggin more clear. These error codes are added 91 // to generic error strings to provide a higher degree of details. 92 // Changing these values can lead to problems when matching native debug 93 // logs with the actual cause of error. 94 enum ErrorCode { 95 // An unspecified error occured. 96 UNKNOWN_ERROR = 0, 97 98 // Failed to create an audio input stream. 99 STREAM_CREATE_ERROR, // = 1 100 101 // Failed to open an audio input stream. 102 STREAM_OPEN_ERROR, // = 2 103 104 // Native input stream reports an error. Exact reason differs between 105 // platforms. 106 STREAM_ERROR, // = 3 107 108 // This can happen if a capture device has been removed or disabled. 109 NO_DATA_ERROR, // = 4 110 }; 111 112 // An event handler that receives events from the AudioInputController. The 113 // following methods are all called on the audio thread. 114 class MEDIA_EXPORT EventHandler { 115 public: 116 virtual void OnCreated(AudioInputController* controller) = 0; 117 virtual void OnRecording(AudioInputController* controller) = 0; 118 virtual void OnError(AudioInputController* controller, 119 ErrorCode error_code) = 0; 120 virtual void OnData(AudioInputController* controller, 121 const AudioBus* data) = 0; 122 virtual void OnLog(AudioInputController* controller, 123 const std::string& message) = 0; 124 125 protected: 126 virtual ~EventHandler() {} 127 }; 128 129 // A synchronous writer interface used by AudioInputController for 130 // synchronous writing. 131 class SyncWriter { 132 public: 133 virtual ~SyncWriter() {} 134 135 // Notify the synchronous writer about the number of bytes in the 136 // soundcard which has been recorded. 137 virtual void UpdateRecordedBytes(uint32 bytes) = 0; 138 139 // Write certain amount of data from |data|. 140 virtual void Write(const AudioBus* data, 141 double volume, 142 bool key_pressed) = 0; 143 144 // Close this synchronous writer. 145 virtual void Close() = 0; 146 }; 147 148 // AudioInputController::Create() can use the currently registered Factory 149 // to create the AudioInputController. Factory is intended for testing only. 150 // |user_input_monitor| is used for typing detection and can be NULL. 151 class Factory { 152 public: 153 virtual AudioInputController* Create( 154 AudioManager* audio_manager, 155 EventHandler* event_handler, 156 AudioParameters params, 157 UserInputMonitor* user_input_monitor) = 0; 158 159 protected: 160 virtual ~Factory() {} 161 }; 162 163 // Factory method for creating an AudioInputController. 164 // The audio device will be created on the audio thread, and when that is 165 // done, the event handler will receive an OnCreated() call from that same 166 // thread. |device_id| is the unique ID of the audio device to be opened. 167 // |user_input_monitor| is used for typing detection and can be NULL. 168 static scoped_refptr<AudioInputController> Create( 169 AudioManager* audio_manager, 170 EventHandler* event_handler, 171 const AudioParameters& params, 172 const std::string& device_id, 173 UserInputMonitor* user_input_monitor); 174 175 // Sets the factory used by the static method Create(). AudioInputController 176 // does not take ownership of |factory|. A value of NULL results in an 177 // AudioInputController being created directly. 178 static void set_factory_for_testing(Factory* factory) { factory_ = factory; } 179 AudioInputStream* stream_for_testing() { return stream_; } 180 181 // Factory method for creating an AudioInputController for low-latency mode. 182 // The audio device will be created on the audio thread, and when that is 183 // done, the event handler will receive an OnCreated() call from that same 184 // thread. |user_input_monitor| is used for typing detection and can be NULL. 185 static scoped_refptr<AudioInputController> CreateLowLatency( 186 AudioManager* audio_manager, 187 EventHandler* event_handler, 188 const AudioParameters& params, 189 const std::string& device_id, 190 // External synchronous writer for audio controller. 191 SyncWriter* sync_writer, 192 UserInputMonitor* user_input_monitor); 193 194 // Factory method for creating an AudioInputController for low-latency mode, 195 // taking ownership of |stream|. The stream will be opened on the audio 196 // thread, and when that is done, the event handler will receive an 197 // OnCreated() call from that same thread. |user_input_monitor| is used for 198 // typing detection and can be NULL. 199 static scoped_refptr<AudioInputController> CreateForStream( 200 const scoped_refptr<base::SingleThreadTaskRunner>& task_runner, 201 EventHandler* event_handler, 202 AudioInputStream* stream, 203 // External synchronous writer for audio controller. 204 SyncWriter* sync_writer, 205 UserInputMonitor* user_input_monitor); 206 207 // Starts recording using the created audio input stream. 208 // This method is called on the creator thread. 209 virtual void Record(); 210 211 // Closes the audio input stream. The state is changed and the resources 212 // are freed on the audio thread. |closed_task| is then executed on the thread 213 // that called Close(). 214 // Callbacks (EventHandler and SyncWriter) must exist until |closed_task| 215 // is called. 216 // It is safe to call this method more than once. Calls after the first one 217 // will have no effect. 218 // This method trampolines to the audio thread. 219 virtual void Close(const base::Closure& closed_task); 220 221 // Sets the capture volume of the input stream. The value 0.0 corresponds 222 // to muted and 1.0 to maximum volume. 223 virtual void SetVolume(double volume); 224 225 // Sets the Automatic Gain Control (AGC) state of the input stream. 226 // Changing the AGC state is not supported while recording is active. 227 virtual void SetAutomaticGainControl(bool enabled); 228 229 // AudioInputCallback implementation. Threading details depends on the 230 // device-specific implementation. 231 virtual void OnData(AudioInputStream* stream, 232 const AudioBus* source, 233 uint32 hardware_delay_bytes, 234 double volume) OVERRIDE; 235 virtual void OnError(AudioInputStream* stream) OVERRIDE; 236 237 bool SharedMemoryAndSyncSocketMode() const { return sync_writer_ != NULL; } 238 239 protected: 240 friend class base::RefCountedThreadSafe<AudioInputController>; 241 242 // Internal state of the source. 243 enum State { 244 CREATED, 245 RECORDING, 246 CLOSED 247 }; 248 249 AudioInputController(EventHandler* handler, 250 SyncWriter* sync_writer, 251 UserInputMonitor* user_input_monitor); 252 virtual ~AudioInputController(); 253 254 // Methods called on the audio thread (owned by the AudioManager). 255 void DoCreate(AudioManager* audio_manager, const AudioParameters& params, 256 const std::string& device_id); 257 void DoCreateForStream(AudioInputStream* stream_to_control, 258 bool enable_nodata_timer); 259 void DoRecord(); 260 void DoClose(); 261 void DoReportError(); 262 void DoSetVolume(double volume); 263 void DoSetAutomaticGainControl(bool enabled); 264 void DoOnData(scoped_ptr<AudioBus> data); 265 void DoLogAudioLevel(float level_dbfs); 266 267 // Method to check if we get recorded data after a stream was started, 268 // and log the result to UMA. 269 void FirstCheckForNoData(); 270 271 // Method which ensures that OnError() is triggered when data recording 272 // times out. Called on the audio thread. 273 void DoCheckForNoData(); 274 275 // Helper method that stops, closes, and NULL:s |*stream_|. 276 void DoStopCloseAndClearStream(); 277 278 void SetDataIsActive(bool enabled); 279 bool GetDataIsActive(); 280 281 // Gives access to the task runner of the creating thread. 282 scoped_refptr<base::SingleThreadTaskRunner> creator_task_runner_; 283 284 // The task runner of audio-manager thread that this object runs on. 285 scoped_refptr<base::SingleThreadTaskRunner> task_runner_; 286 287 // Contains the AudioInputController::EventHandler which receives state 288 // notifications from this class. 289 EventHandler* handler_; 290 291 // Pointer to the audio input stream object. 292 AudioInputStream* stream_; 293 294 // |no_data_timer_| is used to call OnError() when we stop receiving 295 // OnData() calls. This can occur when an audio input device is unplugged 296 // whilst recording on Windows. 297 // See http://crbug.com/79936 for details. 298 // This member is only touched by the audio thread. 299 scoped_ptr<base::Timer> no_data_timer_; 300 301 // This flag is used to signal that we are receiving OnData() calls, i.e, 302 // that data is active. It can be touched by the audio thread and by the 303 // low-level audio thread which calls OnData(). E.g. on Windows, the 304 // low-level audio thread is called wasapi_capture_thread. 305 base::subtle::Atomic32 data_is_active_; 306 307 // |state_| is written on the audio thread and is read on the hardware audio 308 // thread. These operations need to be locked. But lock is not required for 309 // reading on the audio input controller thread. 310 State state_; 311 312 base::Lock lock_; 313 314 // SyncWriter is used only in low-latency mode for synchronous writing. 315 SyncWriter* sync_writer_; 316 317 static Factory* factory_; 318 319 double max_volume_; 320 321 UserInputMonitor* user_input_monitor_; 322 323 #if defined(AUDIO_POWER_MONITORING) 324 // Scans audio samples from OnData() as input to compute audio levels. 325 scoped_ptr<AudioPowerMonitor> audio_level_; 326 327 // We need these to be able to feed data to the AudioPowerMonitor. 328 media::AudioParameters audio_params_; 329 base::TimeTicks last_audio_level_log_time_; 330 #endif 331 332 size_t prev_key_down_count_; 333 334 DISALLOW_COPY_AND_ASSIGN(AudioInputController); 335 }; 336 337 } // namespace media 338 339 #endif // MEDIA_AUDIO_AUDIO_INPUT_CONTROLLER_H_ 340