1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef AUDIORECORD_H_ 18 #define AUDIORECORD_H_ 19 20 #include <binder/IMemory.h> 21 #include <cutils/sched_policy.h> 22 #include <media/AudioSystem.h> 23 #include <media/IAudioRecord.h> 24 #include <system/audio.h> 25 #include <utils/RefBase.h> 26 #include <utils/Errors.h> 27 #include <utils/threads.h> 28 29 namespace android { 30 31 class audio_track_cblk_t; 32 class AudioRecordClientProxy; 33 34 // ---------------------------------------------------------------------------- 35 36 class AudioRecord : virtual public RefBase 37 { 38 public: 39 40 static const int DEFAULT_SAMPLE_RATE = 8000; 41 42 /* Events used by AudioRecord callback function (callback_t). 43 * Keep in sync with frameworks/base/media/java/android/media/AudioRecord.java NATIVE_EVENT_*. 44 */ 45 enum event_type { 46 EVENT_MORE_DATA = 0, // Request to read more data from PCM buffer. 47 EVENT_OVERRUN = 1, // PCM buffer overrun occurred. 48 EVENT_MARKER = 2, // Record head is at the specified marker position 49 // (See setMarkerPosition()). 50 EVENT_NEW_POS = 3, // Record head is at a new position 51 // (See setPositionUpdatePeriod()). 52 }; 53 54 /* Client should declare Buffer on the stack and pass address to obtainBuffer() 55 * and releaseBuffer(). See also callback_t for EVENT_MORE_DATA. 56 */ 57 58 class Buffer 59 { 60 public: 61 size_t frameCount; // number of sample frames corresponding to size; 62 // on input it is the number of frames available, 63 // on output is the number of frames actually drained 64 65 size_t size; // total size in bytes == frameCount * frameSize 66 union { 67 void* raw; 68 short* i16; // signed 16-bit 69 int8_t* i8; // unsigned 8-bit, offset by 0x80 70 }; 71 }; 72 73 /* As a convenience, if a callback is supplied, a handler thread 74 * is automatically created with the appropriate priority. This thread 75 * invokes the callback when a new buffer becomes ready or various conditions occur. 76 * Parameters: 77 * 78 * event: type of event notified (see enum AudioRecord::event_type). 79 * user: Pointer to context for use by the callback receiver. 80 * info: Pointer to optional parameter according to event type: 81 * - EVENT_MORE_DATA: pointer to AudioRecord::Buffer struct. The callback must not read 82 * more bytes than indicated by 'size' field and update 'size' if fewer bytes are 83 * consumed. 84 * - EVENT_OVERRUN: unused. 85 * - EVENT_MARKER: pointer to const uint32_t containing the marker position in frames. 86 * - EVENT_NEW_POS: pointer to const uint32_t containing the new position in frames. 87 */ 88 89 typedef void (*callback_t)(int event, void* user, void *info); 90 91 /* Returns the minimum frame count required for the successful creation of 92 * an AudioRecord object. 93 * Returned status (from utils/Errors.h) can be: 94 * - NO_ERROR: successful operation 95 * - NO_INIT: audio server or audio hardware not initialized 96 * - BAD_VALUE: unsupported configuration 97 */ 98 99 static status_t getMinFrameCount(size_t* frameCount, 100 uint32_t sampleRate, 101 audio_format_t format, 102 audio_channel_mask_t channelMask); 103 104 /* Constructs an uninitialized AudioRecord. No connection with 105 * AudioFlinger takes place. 106 */ 107 AudioRecord(); 108 109 /* Creates an AudioRecord object and registers it with AudioFlinger. 110 * Once created, the track needs to be started before it can be used. 111 * Unspecified values are set to the audio hardware's current 112 * values. 113 * 114 * Parameters: 115 * 116 * inputSource: Select the audio input to record to (e.g. AUDIO_SOURCE_DEFAULT). 117 * sampleRate: Track sampling rate in Hz. 118 * format: Audio format (e.g AUDIO_FORMAT_PCM_16_BIT for signed 119 * 16 bits per sample). 120 * channelMask: Channel mask. 121 * frameCount: Minimum size of track PCM buffer in frames. This defines the 122 * application's contribution to the 123 * latency of the track. The actual size selected by the AudioRecord could 124 * be larger if the requested size is not compatible with current audio HAL 125 * latency. Zero means to use a default value. 126 * cbf: Callback function. If not null, this function is called periodically 127 * to consume new PCM data. 128 * user: Context for use by the callback receiver. 129 * notificationFrames: The callback function is called each time notificationFrames PCM 130 * frames are ready in record track output buffer. 131 * sessionId: Not yet supported. 132 */ 133 134 AudioRecord(audio_source_t inputSource, 135 uint32_t sampleRate = 0, 136 audio_format_t format = AUDIO_FORMAT_DEFAULT, 137 audio_channel_mask_t channelMask = AUDIO_CHANNEL_IN_MONO, 138 int frameCount = 0, 139 callback_t cbf = NULL, 140 void* user = NULL, 141 int notificationFrames = 0, 142 int sessionId = 0); 143 144 145 /* Terminates the AudioRecord and unregisters it from AudioFlinger. 146 * Also destroys all resources associated with the AudioRecord. 147 */ 148 ~AudioRecord(); 149 150 151 /* Initialize an uninitialized AudioRecord. 152 * Returned status (from utils/Errors.h) can be: 153 * - NO_ERROR: successful intialization 154 * - INVALID_OPERATION: AudioRecord is already intitialized or record device is already in use 155 * - BAD_VALUE: invalid parameter (channels, format, sampleRate...) 156 * - NO_INIT: audio server or audio hardware not initialized 157 * - PERMISSION_DENIED: recording is not allowed for the requesting process 158 */ 159 status_t set(audio_source_t inputSource = AUDIO_SOURCE_DEFAULT, 160 uint32_t sampleRate = 0, 161 audio_format_t format = AUDIO_FORMAT_DEFAULT, 162 audio_channel_mask_t channelMask = AUDIO_CHANNEL_IN_MONO, 163 int frameCount = 0, 164 callback_t cbf = NULL, 165 void* user = NULL, 166 int notificationFrames = 0, 167 bool threadCanCallJava = false, 168 int sessionId = 0); 169 170 171 /* Result of constructing the AudioRecord. This must be checked 172 * before using any AudioRecord API (except for set()), because using 173 * an uninitialized AudioRecord produces undefined results. 174 * See set() method above for possible return codes. 175 */ 176 status_t initCheck() const; 177 178 /* Returns this track's estimated latency in milliseconds. 179 * This includes the latency due to AudioRecord buffer size, 180 * and audio hardware driver. 181 */ 182 uint32_t latency() const; 183 184 /* getters, see constructor and set() */ 185 186 audio_format_t format() const; 187 uint32_t channelCount() const; 188 size_t frameCount() const; frameSize()189 size_t frameSize() const { return mFrameSize; } 190 audio_source_t inputSource() const; 191 192 193 /* After it's created the track is not active. Call start() to 194 * make it active. If set, the callback will start being called. 195 * If event is not AudioSystem::SYNC_EVENT_NONE, the capture start will be delayed until 196 * the specified event occurs on the specified trigger session. 197 */ 198 status_t start(AudioSystem::sync_event_t event = AudioSystem::SYNC_EVENT_NONE, 199 int triggerSession = 0); 200 201 /* Stop a track. If set, the callback will cease being called and 202 * obtainBuffer returns STOPPED. Note that obtainBuffer() still works 203 * and will drain buffers until the pool is exhausted. 204 */ 205 void stop(); 206 bool stopped() const; 207 208 /* Get sample rate for this record track in Hz. 209 */ 210 uint32_t getSampleRate() const; 211 212 /* Sets marker position. When record reaches the number of frames specified, 213 * a callback with event type EVENT_MARKER is called. Calling setMarkerPosition 214 * with marker == 0 cancels marker notification callback. 215 * If the AudioRecord has been opened with no callback function associated, 216 * the operation will fail. 217 * 218 * Parameters: 219 * 220 * marker: marker position expressed in frames. 221 * 222 * Returned status (from utils/Errors.h) can be: 223 * - NO_ERROR: successful operation 224 * - INVALID_OPERATION: the AudioRecord has no callback installed. 225 */ 226 status_t setMarkerPosition(uint32_t marker); 227 status_t getMarkerPosition(uint32_t *marker) const; 228 229 230 /* Sets position update period. Every time the number of frames specified has been recorded, 231 * a callback with event type EVENT_NEW_POS is called. 232 * Calling setPositionUpdatePeriod with updatePeriod == 0 cancels new position notification 233 * callback. 234 * If the AudioRecord has been opened with no callback function associated, 235 * the operation will fail. 236 * 237 * Parameters: 238 * 239 * updatePeriod: position update notification period expressed in frames. 240 * 241 * Returned status (from utils/Errors.h) can be: 242 * - NO_ERROR: successful operation 243 * - INVALID_OPERATION: the AudioRecord has no callback installed. 244 */ 245 status_t setPositionUpdatePeriod(uint32_t updatePeriod); 246 status_t getPositionUpdatePeriod(uint32_t *updatePeriod) const; 247 248 249 /* Gets record head position. The position is the total number of frames 250 * recorded since record start. 251 * 252 * Parameters: 253 * 254 * position: Address where to return record head position within AudioRecord buffer. 255 * 256 * Returned status (from utils/Errors.h) can be: 257 * - NO_ERROR: successful operation 258 * - BAD_VALUE: position is NULL 259 */ 260 status_t getPosition(uint32_t *position) const; 261 262 /* Returns a handle on the audio input used by this AudioRecord. 263 * 264 * Parameters: 265 * none. 266 * 267 * Returned value: 268 * handle on audio hardware input 269 */ 270 audio_io_handle_t getInput() const; 271 272 /* Returns the audio session ID associated with this AudioRecord. 273 * 274 * Parameters: 275 * none. 276 * 277 * Returned value: 278 * AudioRecord session ID. 279 */ 280 int getSessionId() const; 281 282 /* Obtains a buffer of "frameCount" frames. The buffer must be 283 * drained entirely, and then released with releaseBuffer(). 284 * If the track is stopped, obtainBuffer() returns 285 * STOPPED instead of NO_ERROR as long as there are buffers available, 286 * at which point NO_MORE_BUFFERS is returned. 287 * Buffers will be returned until the pool 288 * is exhausted, at which point obtainBuffer() will either block 289 * or return WOULD_BLOCK depending on the value of the "blocking" 290 * parameter. 291 * 292 * Interpretation of waitCount: 293 * +n limits wait time to n * WAIT_PERIOD_MS, 294 * -1 causes an (almost) infinite wait time, 295 * 0 non-blocking. 296 */ 297 298 enum { 299 NO_MORE_BUFFERS = 0x80000001, // same name in AudioFlinger.h, ok to be different value 300 STOPPED = 1 301 }; 302 303 status_t obtainBuffer(Buffer* audioBuffer, int32_t waitCount); 304 305 /* Release an emptied buffer of "frameCount" frames for AudioFlinger to re-fill. */ 306 void releaseBuffer(Buffer* audioBuffer); 307 308 309 /* As a convenience we provide a read() interface to the audio buffer. 310 * This is implemented on top of obtainBuffer/releaseBuffer. 311 */ 312 ssize_t read(void* buffer, size_t size); 313 314 /* Return the number of input frames lost in the audio driver since the last call of this 315 * function. Audio driver is expected to reset the value to 0 and restart counting upon 316 * returning the current value by this function call. Such loss typically occurs when the 317 * user space process is blocked longer than the capacity of audio driver buffers. 318 * Units: the number of input audio frames. 319 */ 320 unsigned int getInputFramesLost() const; 321 322 private: 323 /* copying audio record objects is not allowed */ 324 AudioRecord(const AudioRecord& other); 325 AudioRecord& operator = (const AudioRecord& other); 326 327 /* a small internal class to handle the callback */ 328 class AudioRecordThread : public Thread 329 { 330 public: 331 AudioRecordThread(AudioRecord& receiver, bool bCanCallJava = false); 332 333 // Do not call Thread::requestExitAndWait() without first calling requestExit(). 334 // Thread::requestExitAndWait() is not virtual, and the implementation doesn't do enough. 335 virtual void requestExit(); 336 337 void pause(); // suspend thread from execution at next loop boundary 338 void resume(); // allow thread to execute, if not requested to exit 339 340 private: 341 friend class AudioRecord; 342 virtual bool threadLoop(); 343 AudioRecord& mReceiver; 344 virtual ~AudioRecordThread(); 345 Mutex mMyLock; // Thread::mLock is private 346 Condition mMyCond; // Thread::mThreadExitedCondition is private 347 bool mPaused; // whether thread is currently paused 348 }; 349 350 // body of AudioRecordThread::threadLoop() 351 bool processAudioBuffer(const sp<AudioRecordThread>& thread); 352 353 status_t openRecord_l(uint32_t sampleRate, 354 audio_format_t format, 355 size_t frameCount, 356 audio_io_handle_t input); 357 audio_io_handle_t getInput_l(); 358 status_t restoreRecord_l(audio_track_cblk_t*& cblk); 359 360 sp<AudioRecordThread> mAudioRecordThread; 361 mutable Mutex mLock; 362 363 bool mActive; // protected by mLock 364 365 // for client callback handler 366 callback_t mCbf; // callback handler for events, or NULL 367 void* mUserData; 368 369 // for notification APIs 370 uint32_t mNotificationFrames; 371 uint32_t mRemainingFrames; 372 uint32_t mMarkerPosition; // in frames 373 bool mMarkerReached; 374 uint32_t mNewPosition; // in frames 375 uint32_t mUpdatePeriod; // in ms 376 377 // constant after constructor or set() 378 uint32_t mSampleRate; 379 size_t mFrameCount; 380 audio_format_t mFormat; 381 uint8_t mChannelCount; 382 size_t mFrameSize; // app-level frame size == AudioFlinger frame size 383 audio_source_t mInputSource; 384 status_t mStatus; 385 uint32_t mLatency; 386 audio_channel_mask_t mChannelMask; 387 audio_io_handle_t mInput; // returned by AudioSystem::getInput() 388 int mSessionId; 389 390 // may be changed if IAudioRecord object is re-created 391 sp<IAudioRecord> mAudioRecord; 392 sp<IMemory> mCblkMemory; 393 audio_track_cblk_t* mCblk; 394 void* mBuffers; // starting address of buffers in shared memory 395 396 int mPreviousPriority; // before start() 397 SchedPolicy mPreviousSchedulingGroup; 398 AudioRecordClientProxy* mProxy; 399 }; 400 401 }; // namespace android 402 403 #endif /*AUDIORECORD_H_*/ 404