AudioTrack.java revision b282e08ab641d4fc74d0324b7a0ce30926638dd5
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 17package android.media; 18 19import java.lang.ref.WeakReference; 20import java.lang.IllegalArgumentException; 21import java.lang.IllegalStateException; 22 23import android.os.Handler; 24import android.os.Looper; 25import android.os.Message; 26import android.media.AudioManager; 27import android.util.Log; 28 29 30/** 31 * The AudioTrack class manages and plays a single audio resource for Java applications. 32 * It allows streaming PCM audio buffers to the audio hardware for playback. This is 33 * achieved by "pushing" the data to the AudioTrack object using one of the 34 * {@link #write(byte[], int, int)} and {@link #write(short[], int, int)} methods. 35 * 36 * <p>An AudioTrack instance can operate under two modes: static or streaming.<br> 37 * In Streaming mode, the application writes a continuous stream of data to the AudioTrack, using 38 * one of the {@code write()} methods. These are blocking and return when the data has been 39 * transferred from the Java layer to the native layer and queued for playback. The streaming 40 * mode is most useful when playing blocks of audio data that for instance are: 41 * 42 * <ul> 43 * <li>too big to fit in memory because of the duration of the sound to play,</li> 44 * <li>too big to fit in memory because of the characteristics of the audio data 45 * (high sampling rate, bits per sample ...)</li> 46 * <li>received or generated while previously queued audio is playing.</li> 47 * </ul> 48 * 49 * The static mode should be chosen when dealing with short sounds that fit in memory and 50 * that need to be played with the smallest latency possible. The static mode will 51 * therefore be preferred for UI and game sounds that are played often, and with the 52 * smallest overhead possible. 53 * 54 * <p>Upon creation, an AudioTrack object initializes its associated audio buffer. 55 * The size of this buffer, specified during the construction, determines how long an AudioTrack 56 * can play before running out of data.<br> 57 * For an AudioTrack using the static mode, this size is the maximum size of the sound that can 58 * be played from it.<br> 59 * For the streaming mode, data will be written to the hardware in chunks of 60 * sizes less than or equal to the total buffer size. 61 */ 62public class AudioTrack 63{ 64 //--------------------------------------------------------- 65 // Constants 66 //-------------------- 67 /** Minimum value for a channel volume */ 68 private static final float VOLUME_MIN = 0.0f; 69 /** Maximum value for a channel volume */ 70 private static final float VOLUME_MAX = 1.0f; 71 72 /** indicates AudioTrack state is stopped */ 73 public static final int PLAYSTATE_STOPPED = 1; // matches SL_PLAYSTATE_STOPPED 74 /** indicates AudioTrack state is paused */ 75 public static final int PLAYSTATE_PAUSED = 2; // matches SL_PLAYSTATE_PAUSED 76 /** indicates AudioTrack state is playing */ 77 public static final int PLAYSTATE_PLAYING = 3; // matches SL_PLAYSTATE_PLAYING 78 79 // keep these values in sync with android_media_AudioTrack.cpp 80 /** 81 * Creation mode where audio data is transferred from Java to the native layer 82 * only once before the audio starts playing. 83 */ 84 public static final int MODE_STATIC = 0; 85 /** 86 * Creation mode where audio data is streamed from Java to the native layer 87 * as the audio is playing. 88 */ 89 public static final int MODE_STREAM = 1; 90 91 /** 92 * State of an AudioTrack that was not successfully initialized upon creation. 93 */ 94 public static final int STATE_UNINITIALIZED = 0; 95 /** 96 * State of an AudioTrack that is ready to be used. 97 */ 98 public static final int STATE_INITIALIZED = 1; 99 /** 100 * State of a successfully initialized AudioTrack that uses static data, 101 * but that hasn't received that data yet. 102 */ 103 public static final int STATE_NO_STATIC_DATA = 2; 104 105 // Error codes: 106 // to keep in sync with frameworks/base/core/jni/android_media_AudioTrack.cpp 107 /** 108 * Denotes a successful operation. 109 */ 110 public static final int SUCCESS = 0; 111 /** 112 * Denotes a generic operation failure. 113 */ 114 public static final int ERROR = -1; 115 /** 116 * Denotes a failure due to the use of an invalid value. 117 */ 118 public static final int ERROR_BAD_VALUE = -2; 119 /** 120 * Denotes a failure due to the improper use of a method. 121 */ 122 public static final int ERROR_INVALID_OPERATION = -3; 123 124 private static final int ERROR_NATIVESETUP_AUDIOSYSTEM = -16; 125 private static final int ERROR_NATIVESETUP_INVALIDCHANNELMASK = -17; 126 private static final int ERROR_NATIVESETUP_INVALIDFORMAT = -18; 127 private static final int ERROR_NATIVESETUP_INVALIDSTREAMTYPE = -19; 128 private static final int ERROR_NATIVESETUP_NATIVEINITFAILED = -20; 129 130 // Events: 131 // to keep in sync with frameworks/base/include/media/AudioTrack.h 132 /** 133 * Event id denotes when playback head has reached a previously set marker. 134 */ 135 private static final int NATIVE_EVENT_MARKER = 3; 136 /** 137 * Event id denotes when previously set update period has elapsed during playback. 138 */ 139 private static final int NATIVE_EVENT_NEW_POS = 4; 140 141 private final static String TAG = "AudioTrack-Java"; 142 143 144 //-------------------------------------------------------------------------- 145 // Member variables 146 //-------------------- 147 /** 148 * Indicates the state of the AudioTrack instance. 149 */ 150 private int mState = STATE_UNINITIALIZED; 151 /** 152 * Indicates the play state of the AudioTrack instance. 153 */ 154 private int mPlayState = PLAYSTATE_STOPPED; 155 /** 156 * Lock to make sure mPlayState updates are reflecting the actual state of the object. 157 */ 158 private final Object mPlayStateLock = new Object(); 159 /** 160 * The listener the AudioTrack notifies when the playback position reaches a marker 161 * or for periodic updates during the progression of the playback head. 162 * @see #setPlaybackPositionUpdateListener(OnPlaybackPositionUpdateListener) 163 */ 164 private OnPlaybackPositionUpdateListener mPositionListener = null; 165 /** 166 * Lock to protect event listener updates against event notifications. 167 */ 168 private final Object mPositionListenerLock = new Object(); 169 /** 170 * Size of the native audio buffer. 171 */ 172 private int mNativeBufferSizeInBytes = 0; 173 /** 174 * Handler for marker events coming from the native code. 175 */ 176 private NativeEventHandlerDelegate mEventHandlerDelegate = null; 177 /** 178 * Looper associated with the thread that creates the AudioTrack instance. 179 */ 180 private Looper mInitializationLooper = null; 181 /** 182 * The audio data sampling rate in Hz. 183 */ 184 private int mSampleRate; // initialized by all constructors 185 /** 186 * The number of audio output channels (1 is mono, 2 is stereo). 187 */ 188 private int mChannelCount = 1; 189 /** 190 * The audio channel mask. 191 */ 192 private int mChannels = AudioFormat.CHANNEL_OUT_MONO; 193 194 /** 195 * The type of the audio stream to play. See 196 * {@link AudioManager#STREAM_VOICE_CALL}, {@link AudioManager#STREAM_SYSTEM}, 197 * {@link AudioManager#STREAM_RING}, {@link AudioManager#STREAM_MUSIC}, 198 * {@link AudioManager#STREAM_ALARM}, {@link AudioManager#STREAM_NOTIFICATION}, and 199 * {@link AudioManager#STREAM_DTMF}. 200 */ 201 private int mStreamType = AudioManager.STREAM_MUSIC; 202 /** 203 * The way audio is consumed by the hardware, streaming or static. 204 */ 205 private int mDataLoadMode = MODE_STREAM; 206 /** 207 * The current audio channel configuration. 208 */ 209 private int mChannelConfiguration = AudioFormat.CHANNEL_OUT_MONO; 210 /** 211 * The encoding of the audio samples. 212 * @see AudioFormat#ENCODING_PCM_8BIT 213 * @see AudioFormat#ENCODING_PCM_16BIT 214 */ 215 private int mAudioFormat = AudioFormat.ENCODING_PCM_16BIT; 216 /** 217 * Audio session ID 218 */ 219 private int mSessionId = 0; 220 221 222 //-------------------------------- 223 // Used exclusively by native code 224 //-------------------- 225 /** 226 * Accessed by native methods: provides access to C++ AudioTrack object. 227 */ 228 @SuppressWarnings("unused") 229 private int mNativeTrackInJavaObj; 230 /** 231 * Accessed by native methods: provides access to the JNI data (i.e. resources used by 232 * the native AudioTrack object, but not stored in it). 233 */ 234 @SuppressWarnings("unused") 235 private int mJniData; 236 237 238 //-------------------------------------------------------------------------- 239 // Constructor, Finalize 240 //-------------------- 241 /** 242 * Class constructor. 243 * @param streamType the type of the audio stream. See 244 * {@link AudioManager#STREAM_VOICE_CALL}, {@link AudioManager#STREAM_SYSTEM}, 245 * {@link AudioManager#STREAM_RING}, {@link AudioManager#STREAM_MUSIC}, 246 * {@link AudioManager#STREAM_ALARM}, and {@link AudioManager#STREAM_NOTIFICATION}. 247 * @param sampleRateInHz the sample rate expressed in Hertz. 248 * @param channelConfig describes the configuration of the audio channels. 249 * See {@link AudioFormat#CHANNEL_OUT_MONO} and 250 * {@link AudioFormat#CHANNEL_OUT_STEREO} 251 * @param audioFormat the format in which the audio data is represented. 252 * See {@link AudioFormat#ENCODING_PCM_16BIT} and 253 * {@link AudioFormat#ENCODING_PCM_8BIT} 254 * @param bufferSizeInBytes the total size (in bytes) of the buffer where audio data is read 255 * from for playback. If using the AudioTrack in streaming mode, you can write data into 256 * this buffer in smaller chunks than this size. If using the AudioTrack in static mode, 257 * this is the maximum size of the sound that will be played for this instance. 258 * See {@link #getMinBufferSize(int, int, int)} to determine the minimum required buffer size 259 * for the successful creation of an AudioTrack instance in streaming mode. Using values 260 * smaller than getMinBufferSize() will result in an initialization failure. 261 * @param mode streaming or static buffer. See {@link #MODE_STATIC} and {@link #MODE_STREAM} 262 * @throws java.lang.IllegalArgumentException 263 */ 264 public AudioTrack(int streamType, int sampleRateInHz, int channelConfig, int audioFormat, 265 int bufferSizeInBytes, int mode) 266 throws IllegalArgumentException { 267 this(streamType, sampleRateInHz, channelConfig, audioFormat, 268 bufferSizeInBytes, mode, 0); 269 } 270 271 /** 272 * Class constructor with audio session. Use this constructor when the AudioTrack must be 273 * attached to a particular audio session. The primary use of the audio session ID is to 274 * associate audio effects to a particular instance of AudioTrack: if an audio session ID 275 * is provided when creating an AudioEffect, this effect will be applied only to audio tracks 276 * and media players in the same session and not to the output mix. 277 * When an AudioTrack is created without specifying a session, it will create its own session 278 * which can be retreived by calling the {@link #getAudioSessionId()} method. 279 * If a non-zero session ID is provided, this AudioTrack will share effects attached to this 280 * session 281 * with all other media players or audio tracks in the same session, otherwise a new session 282 * will be created for this track if none is supplied. 283 * @param streamType the type of the audio stream. See 284 * {@link AudioManager#STREAM_VOICE_CALL}, {@link AudioManager#STREAM_SYSTEM}, 285 * {@link AudioManager#STREAM_RING}, {@link AudioManager#STREAM_MUSIC}, 286 * {@link AudioManager#STREAM_ALARM}, and {@link AudioManager#STREAM_NOTIFICATION}. 287 * @param sampleRateInHz the sample rate expressed in Hertz. 288 * @param channelConfig describes the configuration of the audio channels. 289 * See {@link AudioFormat#CHANNEL_OUT_MONO} and 290 * {@link AudioFormat#CHANNEL_OUT_STEREO} 291 * @param audioFormat the format in which the audio data is represented. 292 * See {@link AudioFormat#ENCODING_PCM_16BIT} and 293 * {@link AudioFormat#ENCODING_PCM_8BIT} 294 * @param bufferSizeInBytes the total size (in bytes) of the buffer where audio data is read 295 * from for playback. If using the AudioTrack in streaming mode, you can write data into 296 * this buffer in smaller chunks than this size. If using the AudioTrack in static mode, 297 * this is the maximum size of the sound that will be played for this instance. 298 * See {@link #getMinBufferSize(int, int, int)} to determine the minimum required buffer size 299 * for the successful creation of an AudioTrack instance in streaming mode. Using values 300 * smaller than getMinBufferSize() will result in an initialization failure. 301 * @param mode streaming or static buffer. See {@link #MODE_STATIC} and {@link #MODE_STREAM} 302 * @param sessionId Id of audio session the AudioTrack must be attached to 303 * @throws java.lang.IllegalArgumentException 304 */ 305 public AudioTrack(int streamType, int sampleRateInHz, int channelConfig, int audioFormat, 306 int bufferSizeInBytes, int mode, int sessionId) 307 throws IllegalArgumentException { 308 mState = STATE_UNINITIALIZED; 309 310 // remember which looper is associated with the AudioTrack instantiation 311 if ((mInitializationLooper = Looper.myLooper()) == null) { 312 mInitializationLooper = Looper.getMainLooper(); 313 } 314 315 audioParamCheck(streamType, sampleRateInHz, channelConfig, audioFormat, mode); 316 317 audioBuffSizeCheck(bufferSizeInBytes); 318 319 if (sessionId < 0) { 320 throw (new IllegalArgumentException("Invalid audio session ID: "+sessionId)); 321 } 322 323 int[] session = new int[1]; 324 session[0] = sessionId; 325 // native initialization 326 int initResult = native_setup(new WeakReference<AudioTrack>(this), 327 mStreamType, mSampleRate, mChannels, mAudioFormat, 328 mNativeBufferSizeInBytes, mDataLoadMode, session); 329 if (initResult != SUCCESS) { 330 loge("Error code "+initResult+" when initializing AudioTrack."); 331 return; // with mState == STATE_UNINITIALIZED 332 } 333 334 mSessionId = session[0]; 335 336 if (mDataLoadMode == MODE_STATIC) { 337 mState = STATE_NO_STATIC_DATA; 338 } else { 339 mState = STATE_INITIALIZED; 340 } 341 } 342 343 344 // Convenience method for the constructor's parameter checks. 345 // This is where constructor IllegalArgumentException-s are thrown 346 // postconditions: 347 // mStreamType is valid 348 // mChannelCount is valid 349 // mChannels is valid 350 // mAudioFormat is valid 351 // mSampleRate is valid 352 // mDataLoadMode is valid 353 private void audioParamCheck(int streamType, int sampleRateInHz, 354 int channelConfig, int audioFormat, int mode) { 355 356 //-------------- 357 // stream type 358 if( (streamType != AudioManager.STREAM_ALARM) && (streamType != AudioManager.STREAM_MUSIC) 359 && (streamType != AudioManager.STREAM_RING) && (streamType != AudioManager.STREAM_SYSTEM) 360 && (streamType != AudioManager.STREAM_VOICE_CALL) 361 && (streamType != AudioManager.STREAM_NOTIFICATION) 362 && (streamType != AudioManager.STREAM_BLUETOOTH_SCO) 363 && (streamType != AudioManager.STREAM_DTMF)) { 364 throw (new IllegalArgumentException("Invalid stream type.")); 365 } else { 366 mStreamType = streamType; 367 } 368 369 //-------------- 370 // sample rate, note these values are subject to change 371 if ( (sampleRateInHz < 4000) || (sampleRateInHz > 48000) ) { 372 throw (new IllegalArgumentException(sampleRateInHz 373 + "Hz is not a supported sample rate.")); 374 } else { 375 mSampleRate = sampleRateInHz; 376 } 377 378 //-------------- 379 // channel config 380 mChannelConfiguration = channelConfig; 381 382 switch (channelConfig) { 383 case AudioFormat.CHANNEL_OUT_DEFAULT: //AudioFormat.CHANNEL_CONFIGURATION_DEFAULT 384 case AudioFormat.CHANNEL_OUT_MONO: 385 case AudioFormat.CHANNEL_CONFIGURATION_MONO: 386 mChannelCount = 1; 387 mChannels = AudioFormat.CHANNEL_OUT_MONO; 388 break; 389 case AudioFormat.CHANNEL_OUT_STEREO: 390 case AudioFormat.CHANNEL_CONFIGURATION_STEREO: 391 mChannelCount = 2; 392 mChannels = AudioFormat.CHANNEL_OUT_STEREO; 393 break; 394 default: 395 mChannelCount = 0; 396 mChannels = AudioFormat.CHANNEL_INVALID; 397 mChannelConfiguration = AudioFormat.CHANNEL_CONFIGURATION_INVALID; 398 throw(new IllegalArgumentException("Unsupported channel configuration.")); 399 } 400 401 //-------------- 402 // audio format 403 switch (audioFormat) { 404 case AudioFormat.ENCODING_DEFAULT: 405 mAudioFormat = AudioFormat.ENCODING_PCM_16BIT; 406 break; 407 case AudioFormat.ENCODING_PCM_16BIT: 408 case AudioFormat.ENCODING_PCM_8BIT: 409 mAudioFormat = audioFormat; 410 break; 411 default: 412 mAudioFormat = AudioFormat.ENCODING_INVALID; 413 throw(new IllegalArgumentException("Unsupported sample encoding." 414 + " Should be ENCODING_PCM_8BIT or ENCODING_PCM_16BIT.")); 415 } 416 417 //-------------- 418 // audio load mode 419 if ( (mode != MODE_STREAM) && (mode != MODE_STATIC) ) { 420 throw(new IllegalArgumentException("Invalid mode.")); 421 } else { 422 mDataLoadMode = mode; 423 } 424 } 425 426 427 // Convenience method for the contructor's audio buffer size check. 428 // preconditions: 429 // mChannelCount is valid 430 // mAudioFormat is valid 431 // postcondition: 432 // mNativeBufferSizeInBytes is valid (multiple of frame size, positive) 433 private void audioBuffSizeCheck(int audioBufferSize) { 434 // NB: this section is only valid with PCM data. 435 // To update when supporting compressed formats 436 int frameSizeInBytes = mChannelCount 437 * (mAudioFormat == AudioFormat.ENCODING_PCM_8BIT ? 1 : 2); 438 if ((audioBufferSize % frameSizeInBytes != 0) || (audioBufferSize < 1)) { 439 throw (new IllegalArgumentException("Invalid audio buffer size.")); 440 } 441 442 mNativeBufferSizeInBytes = audioBufferSize; 443 } 444 445 446 /** 447 * Releases the native AudioTrack resources. 448 */ 449 public void release() { 450 // even though native_release() stops the native AudioTrack, we need to stop 451 // AudioTrack subclasses too. 452 try { 453 stop(); 454 } catch(IllegalStateException ise) { 455 // don't raise an exception, we're releasing the resources. 456 } 457 native_release(); 458 mState = STATE_UNINITIALIZED; 459 } 460 461 @Override 462 protected void finalize() { 463 native_finalize(); 464 } 465 466 //-------------------------------------------------------------------------- 467 // Getters 468 //-------------------- 469 /** 470 * Returns the minimum valid volume value. Volume values set under this one will 471 * be clamped at this value. 472 * @return the minimum volume expressed as a linear attenuation. 473 */ 474 static public float getMinVolume() { 475 return AudioTrack.VOLUME_MIN; 476 } 477 478 /** 479 * Returns the maximum valid volume value. Volume values set above this one will 480 * be clamped at this value. 481 * @return the maximum volume expressed as a linear attenuation. 482 */ 483 static public float getMaxVolume() { 484 return AudioTrack.VOLUME_MAX; 485 } 486 487 /** 488 * Returns the configured audio data sample rate in Hz 489 */ 490 public int getSampleRate() { 491 return mSampleRate; 492 } 493 494 /** 495 * Returns the current playback rate in Hz. 496 */ 497 public int getPlaybackRate() { 498 return native_get_playback_rate(); 499 } 500 501 /** 502 * Returns the configured audio data format. See {@link AudioFormat#ENCODING_PCM_16BIT} 503 * and {@link AudioFormat#ENCODING_PCM_8BIT}. 504 */ 505 public int getAudioFormat() { 506 return mAudioFormat; 507 } 508 509 /** 510 * Returns the type of audio stream this AudioTrack is configured for. 511 * Compare the result against {@link AudioManager#STREAM_VOICE_CALL}, 512 * {@link AudioManager#STREAM_SYSTEM}, {@link AudioManager#STREAM_RING}, 513 * {@link AudioManager#STREAM_MUSIC}, {@link AudioManager#STREAM_ALARM}, 514 * {@link AudioManager#STREAM_NOTIFICATION}, or {@link AudioManager#STREAM_DTMF}. 515 */ 516 public int getStreamType() { 517 return mStreamType; 518 } 519 520 /** 521 * Returns the configured channel configuration. 522 523 * See {@link AudioFormat#CHANNEL_OUT_MONO} 524 * and {@link AudioFormat#CHANNEL_OUT_STEREO}. 525 */ 526 public int getChannelConfiguration() { 527 return mChannelConfiguration; 528 } 529 530 /** 531 * Returns the configured number of channels. 532 */ 533 public int getChannelCount() { 534 return mChannelCount; 535 } 536 537 /** 538 * Returns the state of the AudioTrack instance. This is useful after the 539 * AudioTrack instance has been created to check if it was initialized 540 * properly. This ensures that the appropriate hardware resources have been 541 * acquired. 542 * @see #STATE_INITIALIZED 543 * @see #STATE_NO_STATIC_DATA 544 * @see #STATE_UNINITIALIZED 545 */ 546 public int getState() { 547 return mState; 548 } 549 550 /** 551 * Returns the playback state of the AudioTrack instance. 552 * @see #PLAYSTATE_STOPPED 553 * @see #PLAYSTATE_PAUSED 554 * @see #PLAYSTATE_PLAYING 555 */ 556 public int getPlayState() { 557 synchronized (mPlayStateLock) { 558 return mPlayState; 559 } 560 } 561 562 /** 563 * Returns the native frame count used by the hardware. 564 */ 565 protected int getNativeFrameCount() { 566 return native_get_native_frame_count(); 567 } 568 569 /** 570 * Returns marker position expressed in frames. 571 */ 572 public int getNotificationMarkerPosition() { 573 return native_get_marker_pos(); 574 } 575 576 /** 577 * Returns the notification update period expressed in frames. 578 */ 579 public int getPositionNotificationPeriod() { 580 return native_get_pos_update_period(); 581 } 582 583 /** 584 * Returns the playback head position expressed in frames 585 */ 586 public int getPlaybackHeadPosition() { 587 return native_get_position(); 588 } 589 590 /** 591 * Returns the hardware output sample rate 592 */ 593 static public int getNativeOutputSampleRate(int streamType) { 594 return native_get_output_sample_rate(streamType); 595 } 596 597 /** 598 * Returns the minimum buffer size required for the successful creation of an AudioTrack 599 * object to be created in the {@link #MODE_STREAM} mode. Note that this size doesn't 600 * guarantee a smooth playback under load, and higher values should be chosen according to 601 * the expected frequency at which the buffer will be refilled with additional data to play. 602 * @param sampleRateInHz the sample rate expressed in Hertz. 603 * @param channelConfig describes the configuration of the audio channels. 604 * See {@link AudioFormat#CHANNEL_OUT_MONO} and 605 * {@link AudioFormat#CHANNEL_OUT_STEREO} 606 * @param audioFormat the format in which the audio data is represented. 607 * See {@link AudioFormat#ENCODING_PCM_16BIT} and 608 * {@link AudioFormat#ENCODING_PCM_8BIT} 609 * @return {@link #ERROR_BAD_VALUE} if an invalid parameter was passed, 610 * or {@link #ERROR} if the implementation was unable to query the hardware for its output 611 * properties, 612 * or the minimum buffer size expressed in bytes. 613 */ 614 static public int getMinBufferSize(int sampleRateInHz, int channelConfig, int audioFormat) { 615 int channelCount = 0; 616 switch(channelConfig) { 617 case AudioFormat.CHANNEL_OUT_MONO: 618 case AudioFormat.CHANNEL_CONFIGURATION_MONO: 619 channelCount = 1; 620 break; 621 case AudioFormat.CHANNEL_OUT_STEREO: 622 case AudioFormat.CHANNEL_CONFIGURATION_STEREO: 623 channelCount = 2; 624 break; 625 default: 626 loge("getMinBufferSize(): Invalid channel configuration."); 627 return AudioTrack.ERROR_BAD_VALUE; 628 } 629 630 if ((audioFormat != AudioFormat.ENCODING_PCM_16BIT) 631 && (audioFormat != AudioFormat.ENCODING_PCM_8BIT)) { 632 loge("getMinBufferSize(): Invalid audio format."); 633 return AudioTrack.ERROR_BAD_VALUE; 634 } 635 636 // sample rate, note these values are subject to change 637 if ( (sampleRateInHz < 4000) || (sampleRateInHz > 48000) ) { 638 loge("getMinBufferSize(): " + sampleRateInHz +"Hz is not a supported sample rate."); 639 return AudioTrack.ERROR_BAD_VALUE; 640 } 641 642 int size = native_get_min_buff_size(sampleRateInHz, channelCount, audioFormat); 643 if ((size == -1) || (size == 0)) { 644 loge("getMinBufferSize(): error querying hardware"); 645 return AudioTrack.ERROR; 646 } 647 else { 648 return size; 649 } 650 } 651 652 /** 653 * Returns the audio session ID. 654 * 655 * @return the ID of the audio session this AudioTrack belongs to. 656 */ 657 public int getAudioSessionId() { 658 return mSessionId; 659 } 660 661 //-------------------------------------------------------------------------- 662 // Initialization / configuration 663 //-------------------- 664 /** 665 * Sets the listener the AudioTrack notifies when a previously set marker is reached or 666 * for each periodic playback head position update. 667 * Notifications will be received in the same thread as the one in which the AudioTrack 668 * instance was created. 669 * @param listener 670 */ 671 public void setPlaybackPositionUpdateListener(OnPlaybackPositionUpdateListener listener) { 672 setPlaybackPositionUpdateListener(listener, null); 673 } 674 675 /** 676 * Sets the listener the AudioTrack notifies when a previously set marker is reached or 677 * for each periodic playback head position update. 678 * Use this method to receive AudioTrack events in the Handler associated with another 679 * thread than the one in which you created the AudioTrack instance. 680 * @param listener 681 * @param handler the Handler that will receive the event notification messages. 682 */ 683 public void setPlaybackPositionUpdateListener(OnPlaybackPositionUpdateListener listener, 684 Handler handler) { 685 synchronized (mPositionListenerLock) { 686 mPositionListener = listener; 687 } 688 if (listener != null) { 689 mEventHandlerDelegate = new NativeEventHandlerDelegate(this, handler); 690 } 691 692 } 693 694 695 696 /** 697 * Sets the specified left/right output volume values on the AudioTrack. Values are clamped 698 * to the ({@link #getMinVolume()}, {@link #getMaxVolume()}) interval if outside this range. 699 * @param leftVolume output attenuation for the left channel. A value of 0.0f is silence, 700 * a value of 1.0f is no attenuation. 701 * @param rightVolume output attenuation for the right channel 702 * @return error code or success, see {@link #SUCCESS}, 703 * {@link #ERROR_INVALID_OPERATION} 704 */ 705 public int setStereoVolume(float leftVolume, float rightVolume) { 706 if (mState != STATE_INITIALIZED) { 707 return ERROR_INVALID_OPERATION; 708 } 709 710 // clamp the volumes 711 if (leftVolume < getMinVolume()) { 712 leftVolume = getMinVolume(); 713 } 714 if (leftVolume > getMaxVolume()) { 715 leftVolume = getMaxVolume(); 716 } 717 if (rightVolume < getMinVolume()) { 718 rightVolume = getMinVolume(); 719 } 720 if (rightVolume > getMaxVolume()) { 721 rightVolume = getMaxVolume(); 722 } 723 724 native_setVolume(leftVolume, rightVolume); 725 726 return SUCCESS; 727 } 728 729 730 /** 731 * Sets the playback sample rate for this track. This sets the sampling rate at which 732 * the audio data will be consumed and played back, not the original sampling rate of the 733 * content. Setting it to half the sample rate of the content will cause the playback to 734 * last twice as long, but will also result in a negative pitch shift. 735 * The valid sample rate range is from 1Hz to twice the value returned by 736 * {@link #getNativeOutputSampleRate(int)}. 737 * @param sampleRateInHz the sample rate expressed in Hz 738 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 739 * {@link #ERROR_INVALID_OPERATION} 740 */ 741 public int setPlaybackRate(int sampleRateInHz) { 742 if (mState != STATE_INITIALIZED) { 743 return ERROR_INVALID_OPERATION; 744 } 745 if (sampleRateInHz <= 0) { 746 return ERROR_BAD_VALUE; 747 } 748 return native_set_playback_rate(sampleRateInHz); 749 } 750 751 752 /** 753 * Sets the position of the notification marker. 754 * @param markerInFrames marker in frames 755 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 756 * {@link #ERROR_INVALID_OPERATION} 757 */ 758 public int setNotificationMarkerPosition(int markerInFrames) { 759 if (mState != STATE_INITIALIZED) { 760 return ERROR_INVALID_OPERATION; 761 } 762 return native_set_marker_pos(markerInFrames); 763 } 764 765 766 /** 767 * Sets the period for the periodic notification event. 768 * @param periodInFrames update period expressed in frames 769 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_INVALID_OPERATION} 770 */ 771 public int setPositionNotificationPeriod(int periodInFrames) { 772 if (mState != STATE_INITIALIZED) { 773 return ERROR_INVALID_OPERATION; 774 } 775 return native_set_pos_update_period(periodInFrames); 776 } 777 778 779 /** 780 * Sets the playback head position. The track must be stopped for the position to be changed. 781 * @param positionInFrames playback head position expressed in frames 782 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 783 * {@link #ERROR_INVALID_OPERATION} 784 */ 785 public int setPlaybackHeadPosition(int positionInFrames) { 786 synchronized(mPlayStateLock) { 787 if ((mPlayState == PLAYSTATE_STOPPED) || (mPlayState == PLAYSTATE_PAUSED)) { 788 return native_set_position(positionInFrames); 789 } else { 790 return ERROR_INVALID_OPERATION; 791 } 792 } 793 } 794 795 /** 796 * Sets the loop points and the loop count. The loop can be infinite. 797 * @param startInFrames loop start marker expressed in frames 798 * @param endInFrames loop end marker expressed in frames 799 * @param loopCount the number of times the loop is looped. 800 * A value of -1 means infinite looping. 801 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 802 * {@link #ERROR_INVALID_OPERATION} 803 */ 804 public int setLoopPoints(int startInFrames, int endInFrames, int loopCount) { 805 if (mDataLoadMode == MODE_STREAM) { 806 return ERROR_INVALID_OPERATION; 807 } 808 return native_set_loop(startInFrames, endInFrames, loopCount); 809 } 810 811 /** 812 * Sets the initialization state of the instance. To be used in an AudioTrack subclass 813 * constructor to set a subclass-specific post-initialization state. 814 * @param state the state of the AudioTrack instance 815 */ 816 protected void setState(int state) { 817 mState = state; 818 } 819 820 821 //--------------------------------------------------------- 822 // Transport control methods 823 //-------------------- 824 /** 825 * Starts playing an AudioTrack. 826 * 827 * @throws IllegalStateException 828 */ 829 public void play() 830 throws IllegalStateException { 831 if (mState != STATE_INITIALIZED) { 832 throw(new IllegalStateException("play() called on uninitialized AudioTrack.")); 833 } 834 835 synchronized(mPlayStateLock) { 836 native_start(); 837 mPlayState = PLAYSTATE_PLAYING; 838 } 839 } 840 841 /** 842 * Stops playing the audio data. 843 * 844 * @throws IllegalStateException 845 */ 846 public void stop() 847 throws IllegalStateException { 848 if (mState != STATE_INITIALIZED) { 849 throw(new IllegalStateException("stop() called on uninitialized AudioTrack.")); 850 } 851 852 // stop playing 853 synchronized(mPlayStateLock) { 854 native_stop(); 855 mPlayState = PLAYSTATE_STOPPED; 856 } 857 } 858 859 /** 860 * Pauses the playback of the audio data. Data that has not been played 861 * back will not be discarded. Subsequent calls to {@link #play} will play 862 * this data back. 863 * 864 * @throws IllegalStateException 865 */ 866 public void pause() 867 throws IllegalStateException { 868 if (mState != STATE_INITIALIZED) { 869 throw(new IllegalStateException("pause() called on uninitialized AudioTrack.")); 870 } 871 //logd("pause()"); 872 873 // pause playback 874 synchronized(mPlayStateLock) { 875 native_pause(); 876 mPlayState = PLAYSTATE_PAUSED; 877 } 878 } 879 880 881 //--------------------------------------------------------- 882 // Audio data supply 883 //-------------------- 884 885 /** 886 * Flushes the audio data currently queued for playback. Any data that has 887 * not been played back will be discarded. 888 */ 889 public void flush() { 890 if (mState == STATE_INITIALIZED) { 891 // flush the data in native layer 892 native_flush(); 893 } 894 895 } 896 897 /** 898 * Writes the audio data to the audio hardware for playback. Will block until 899 * all data has been written to the audio mixer. 900 * Note that the actual playback of this data might occur after this function 901 * returns. This function is thread safe with respect to {@link #stop} calls, 902 * in which case all of the specified data might not be written to the mixer. 903 * 904 * @param audioData the array that holds the data to play. 905 * @param offsetInBytes the offset expressed in bytes in audioData where the data to play 906 * starts. 907 * @param sizeInBytes the number of bytes to read in audioData after the offset. 908 * @return the number of bytes that were written or {@link #ERROR_INVALID_OPERATION} 909 * if the object wasn't properly initialized, or {@link #ERROR_BAD_VALUE} if 910 * the parameters don't resolve to valid data and indexes. 911 */ 912 913 public int write(byte[] audioData, int offsetInBytes, int sizeInBytes) { 914 if ((mDataLoadMode == MODE_STATIC) 915 && (mState == STATE_NO_STATIC_DATA) 916 && (sizeInBytes > 0)) { 917 mState = STATE_INITIALIZED; 918 } 919 920 if (mState != STATE_INITIALIZED) { 921 return ERROR_INVALID_OPERATION; 922 } 923 924 if ( (audioData == null) || (offsetInBytes < 0 ) || (sizeInBytes < 0) 925 || (offsetInBytes + sizeInBytes > audioData.length)) { 926 return ERROR_BAD_VALUE; 927 } 928 929 return native_write_byte(audioData, offsetInBytes, sizeInBytes, mAudioFormat); 930 } 931 932 933 /** 934 * Writes the audio data to the audio hardware for playback. Will block until 935 * all data has been written to the audio mixer. 936 * Note that the actual playback of this data might occur after this function 937 * returns. This function is thread safe with respect to {@link #stop} calls, 938 * in which case all of the specified data might not be written to the mixer. 939 * 940 * @param audioData the array that holds the data to play. 941 * @param offsetInShorts the offset expressed in shorts in audioData where the data to play 942 * starts. 943 * @param sizeInShorts the number of bytes to read in audioData after the offset. 944 * @return the number of shorts that were written or {@link #ERROR_INVALID_OPERATION} 945 * if the object wasn't properly initialized, or {@link #ERROR_BAD_VALUE} if 946 * the parameters don't resolve to valid data and indexes. 947 */ 948 949 public int write(short[] audioData, int offsetInShorts, int sizeInShorts) { 950 if ((mDataLoadMode == MODE_STATIC) 951 && (mState == STATE_NO_STATIC_DATA) 952 && (sizeInShorts > 0)) { 953 mState = STATE_INITIALIZED; 954 } 955 956 if (mState != STATE_INITIALIZED) { 957 return ERROR_INVALID_OPERATION; 958 } 959 960 if ( (audioData == null) || (offsetInShorts < 0 ) || (sizeInShorts < 0) 961 || (offsetInShorts + sizeInShorts > audioData.length)) { 962 return ERROR_BAD_VALUE; 963 } 964 965 return native_write_short(audioData, offsetInShorts, sizeInShorts, mAudioFormat); 966 } 967 968 969 /** 970 * Notifies the native resource to reuse the audio data already loaded in the native 971 * layer. This call is only valid with AudioTrack instances that don't use the streaming 972 * model. 973 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 974 * {@link #ERROR_INVALID_OPERATION} 975 */ 976 public int reloadStaticData() { 977 if (mDataLoadMode == MODE_STREAM) { 978 return ERROR_INVALID_OPERATION; 979 } 980 return native_reload_static(); 981 } 982 983 //-------------------------------------------------------------------------- 984 // Audio effects management 985 //-------------------- 986 987 /** 988 * Attaches an auxiliary effect to the audio track. A typical auxiliary 989 * effect is a reverberation effect which can be applied on any sound source 990 * that directs a certain amount of its energy to this effect. This amount 991 * is defined by setAuxEffectSendLevel(). 992 * {@see #setAuxEffectSendLevel(float)}. 993 * <p>After creating an auxiliary effect (e.g. 994 * {@link android.media.audiofx.EnvironmentalReverb}), retrieve its ID with 995 * {@link android.media.audiofx.AudioEffect#getId()} and use it when calling 996 * this method to attach the audio track to the effect. 997 * <p>To detach the effect from the audio track, call this method with a 998 * null effect id. 999 * 1000 * @param effectId system wide unique id of the effect to attach 1001 * @return error code or success, see {@link #SUCCESS}, 1002 * {@link #ERROR_INVALID_OPERATION}, {@link #ERROR_BAD_VALUE} 1003 */ 1004 public int attachAuxEffect(int effectId) { 1005 if (mState != STATE_INITIALIZED) { 1006 return ERROR_INVALID_OPERATION; 1007 } 1008 return native_attachAuxEffect(effectId); 1009 } 1010 1011 /** 1012 * Sets the send level of the audio track to the attached auxiliary effect 1013 * {@link #attachAuxEffect(int)}. The level value range is 0 to 1.0. 1014 * <p>By default the send level is 0, so even if an effect is attached to the player 1015 * this method must be called for the effect to be applied. 1016 * <p>Note that the passed level value is a raw scalar. UI controls should be scaled 1017 * logarithmically: the gain applied by audio framework ranges from -72dB to 0dB, 1018 * so an appropriate conversion from linear UI input x to level is: 1019 * x == 0 -> level = 0 1020 * 0 < x <= R -> level = 10^(72*(x-R)/20/R) 1021 * 1022 * @param level send level scalar 1023 * @return error code or success, see {@link #SUCCESS}, 1024 * {@link #ERROR_INVALID_OPERATION} 1025 */ 1026 public int setAuxEffectSendLevel(float level) { 1027 if (mState != STATE_INITIALIZED) { 1028 return ERROR_INVALID_OPERATION; 1029 } 1030 // clamp the level 1031 if (level < getMinVolume()) { 1032 level = getMinVolume(); 1033 } 1034 if (level > getMaxVolume()) { 1035 level = getMaxVolume(); 1036 } 1037 native_setAuxEffectSendLevel(level); 1038 return SUCCESS; 1039 } 1040 1041 //--------------------------------------------------------- 1042 // Interface definitions 1043 //-------------------- 1044 /** 1045 * Interface definition for a callback to be invoked when the playback head position of 1046 * an AudioTrack has reached a notification marker or has increased by a certain period. 1047 */ 1048 public interface OnPlaybackPositionUpdateListener { 1049 /** 1050 * Called on the listener to notify it that the previously set marker has been reached 1051 * by the playback head. 1052 */ 1053 void onMarkerReached(AudioTrack track); 1054 1055 /** 1056 * Called on the listener to periodically notify it that the playback head has reached 1057 * a multiple of the notification period. 1058 */ 1059 void onPeriodicNotification(AudioTrack track); 1060 } 1061 1062 1063 //--------------------------------------------------------- 1064 // Inner classes 1065 //-------------------- 1066 /** 1067 * Helper class to handle the forwarding of native events to the appropriate listener 1068 * (potentially) handled in a different thread 1069 */ 1070 private class NativeEventHandlerDelegate { 1071 private final AudioTrack mAudioTrack; 1072 private final Handler mHandler; 1073 1074 NativeEventHandlerDelegate(AudioTrack track, Handler handler) { 1075 mAudioTrack = track; 1076 // find the looper for our new event handler 1077 Looper looper; 1078 if (handler != null) { 1079 looper = handler.getLooper(); 1080 } else { 1081 // no given handler, use the looper the AudioTrack was created in 1082 looper = mInitializationLooper; 1083 } 1084 1085 // construct the event handler with this looper 1086 if (looper != null) { 1087 // implement the event handler delegate 1088 mHandler = new Handler(looper) { 1089 @Override 1090 public void handleMessage(Message msg) { 1091 if (mAudioTrack == null) { 1092 return; 1093 } 1094 OnPlaybackPositionUpdateListener listener = null; 1095 synchronized (mPositionListenerLock) { 1096 listener = mAudioTrack.mPositionListener; 1097 } 1098 switch(msg.what) { 1099 case NATIVE_EVENT_MARKER: 1100 if (listener != null) { 1101 listener.onMarkerReached(mAudioTrack); 1102 } 1103 break; 1104 case NATIVE_EVENT_NEW_POS: 1105 if (listener != null) { 1106 listener.onPeriodicNotification(mAudioTrack); 1107 } 1108 break; 1109 default: 1110 Log.e(TAG, "[ android.media.AudioTrack.NativeEventHandler ] " + 1111 "Unknown event type: " + msg.what); 1112 break; 1113 } 1114 } 1115 }; 1116 } else { 1117 mHandler = null; 1118 } 1119 } 1120 1121 Handler getHandler() { 1122 return mHandler; 1123 } 1124 } 1125 1126 1127 //--------------------------------------------------------- 1128 // Java methods called from the native side 1129 //-------------------- 1130 @SuppressWarnings("unused") 1131 private static void postEventFromNative(Object audiotrack_ref, 1132 int what, int arg1, int arg2, Object obj) { 1133 //logd("Event posted from the native side: event="+ what + " args="+ arg1+" "+arg2); 1134 AudioTrack track = (AudioTrack)((WeakReference)audiotrack_ref).get(); 1135 if (track == null) { 1136 return; 1137 } 1138 1139 if (track.mEventHandlerDelegate != null) { 1140 Message m = 1141 track.mEventHandlerDelegate.getHandler().obtainMessage(what, arg1, arg2, obj); 1142 track.mEventHandlerDelegate.getHandler().sendMessage(m); 1143 } 1144 1145 } 1146 1147 1148 //--------------------------------------------------------- 1149 // Native methods called from the Java side 1150 //-------------------- 1151 1152 private native final int native_setup(Object audiotrack_this, 1153 int streamType, int sampleRate, int nbChannels, int audioFormat, 1154 int buffSizeInBytes, int mode, int[] sessionId); 1155 1156 private native final void native_finalize(); 1157 1158 private native final void native_release(); 1159 1160 private native final void native_start(); 1161 1162 private native final void native_stop(); 1163 1164 private native final void native_pause(); 1165 1166 private native final void native_flush(); 1167 1168 private native final int native_write_byte(byte[] audioData, 1169 int offsetInBytes, int sizeInBytes, int format); 1170 1171 private native final int native_write_short(short[] audioData, 1172 int offsetInShorts, int sizeInShorts, int format); 1173 1174 private native final int native_reload_static(); 1175 1176 private native final int native_get_native_frame_count(); 1177 1178 private native final void native_setVolume(float leftVolume, float rightVolume); 1179 1180 private native final int native_set_playback_rate(int sampleRateInHz); 1181 private native final int native_get_playback_rate(); 1182 1183 private native final int native_set_marker_pos(int marker); 1184 private native final int native_get_marker_pos(); 1185 1186 private native final int native_set_pos_update_period(int updatePeriod); 1187 private native final int native_get_pos_update_period(); 1188 1189 private native final int native_set_position(int position); 1190 private native final int native_get_position(); 1191 1192 private native final int native_set_loop(int start, int end, int loopCount); 1193 1194 static private native final int native_get_output_sample_rate(int streamType); 1195 static private native final int native_get_min_buff_size( 1196 int sampleRateInHz, int channelConfig, int audioFormat); 1197 1198 private native final int native_get_session_id(); 1199 1200 private native final int native_attachAuxEffect(int effectId); 1201 private native final void native_setAuxEffectSendLevel(float level); 1202 1203 //--------------------------------------------------------- 1204 // Utility methods 1205 //------------------ 1206 1207 private static void logd(String msg) { 1208 Log.d(TAG, "[ android.media.AudioTrack ] " + msg); 1209 } 1210 1211 private static void loge(String msg) { 1212 Log.e(TAG, "[ android.media.AudioTrack ] " + msg); 1213 } 1214 1215} 1216