AudioTrack.java revision d24b8183b93e781080b2c16c487e60d51c12da31
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 to stream 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 * <p>An AudioTrack instance can operate under two modes: static of streaming.<br> 36 * The Streaming mode consists in continuously writing data to the AudioTrack, using one 37 * of the write() methods. These are blocking and return when the data has been transferred 38 * from the Java layer to the native layer, and is queued for playback. The streaming mode 39 * is most useful when playing blocks of audio data that for instance are: 40 * <ul> 41 * <li>too big to fit in memory because of the duration of the sound to play,</li> 42 * <li>too big to fit in memory because of the characteristics of the audio data 43 * (high sampling rate, bits per sample ...)</li> 44 * <li>chosen, received or generated as the audio keeps playing.</li> 45 * </ul> 46 * The static mode is to be chosen when dealing with short sounds that fit in memory and 47 * that need to be played with the smallest latency possible. Static mode AudioTrack instances can 48 * play the sound without the need to transfer the audio data from Java to the audio hardware 49 * each time the sound is to be played. The static mode will therefore be preferred for UI and 50 * game sounds that are played often, and with the smallest overhead possible. 51 * <p>Upon creation, an AudioTrack object initializes its associated audio buffer. 52 * The size of this buffer, specified during the construction, determines how long an AudioTrack 53 * can play before running out of data.<br> 54 * For an AudioTrack using the static mode, this size is the maximum size of the sound that can 55 * be played from it.<br> 56 * For the streaming mode, data will be written to the hardware in chunks of 57 * sizes inferior to the total buffer size. 58 */ 59public class AudioTrack 60{ 61 //--------------------------------------------------------- 62 // Constants 63 //-------------------- 64 /** Minimum value for a channel volume */ 65 private static final float VOLUME_MIN = 0.0f; 66 /** Maximum value for a channel volume */ 67 private static final float VOLUME_MAX = 1.0f; 68 69 /** state of an AudioTrack this is stopped */ 70 public static final int PLAYSTATE_STOPPED = 1; // matches SL_PLAYSTATE_STOPPED 71 /** state of an AudioTrack this is paused */ 72 public static final int PLAYSTATE_PAUSED = 2; // matches SL_PLAYSTATE_PAUSED 73 /** state of an AudioTrack this is playing */ 74 public static final int PLAYSTATE_PLAYING = 3; // matches SL_PLAYSTATE_PLAYING 75 76 /** 77 * Creation mode where audio data is transferred from Java to the native layer 78 * only once before the audio starts playing. 79 */ 80 public static final int MODE_STATIC = 0; 81 /** 82 * Creation mode where audio data is streamed from Java to the native layer 83 * as the audio is playing. 84 */ 85 public static final int MODE_STREAM = 1; 86 87 /** 88 * State of an AudioTrack that was not successfully initialized upon creation 89 */ 90 public static final int STATE_UNINITIALIZED = 0; 91 /** 92 * State of an AudioTrack that is ready to be used. 93 */ 94 public static final int STATE_INITIALIZED = 1; 95 /** 96 * State of a successfully initialized AudioTrack that uses static data, 97 * but that hasn't received that data yet. 98 */ 99 public static final int STATE_NO_STATIC_DATA = 2; 100 101 // Error codes: 102 // to keep in sync with frameworks/base/core/jni/android_media_AudioTrack.cpp 103 /** 104 * Denotes a successful operation. 105 */ 106 public static final int SUCCESS = 0; 107 /** 108 * Denotes a generic operation failure. 109 */ 110 public static final int ERROR = -1; 111 /** 112 * Denotes a failure due to the use of an invalid value. 113 */ 114 public static final int ERROR_BAD_VALUE = -2; 115 /** 116 * Denotes a failure due to the improper use of a method. 117 */ 118 public static final int ERROR_INVALID_OPERATION = -3; 119 120 private static final int ERROR_NATIVESETUP_AUDIOSYSTEM = -16; 121 private static final int ERROR_NATIVESETUP_INVALIDCHANNELCOUNT = -17; 122 private static final int ERROR_NATIVESETUP_INVALIDFORMAT = -18; 123 private static final int ERROR_NATIVESETUP_INVALIDSTREAMTYPE = -19; 124 private static final int ERROR_NATIVESETUP_NATIVEINITFAILED = -20; 125 126 // Events: 127 // to keep in sync with frameworks/base/include/media/AudioTrack.h 128 /** 129 * Event id for when the playback head has reached a previously set marker. 130 */ 131 private static final int NATIVE_EVENT_MARKER = 3; 132 /** 133 * Event id for when the previously set update period has passed during playback. 134 */ 135 private static final int NATIVE_EVENT_NEW_POS = 4; 136 137 private final static String TAG = "AudioTrack-Java"; 138 139 140 //-------------------------------------------------------------------------- 141 // Member variables 142 //-------------------- 143 /** 144 * Indicates the state of the AudioTrack instance 145 */ 146 private int mState = STATE_UNINITIALIZED; 147 /** 148 * Indicates the play state of the AudioTrack instance 149 */ 150 private int mPlayState = PLAYSTATE_STOPPED; 151 /** 152 * Lock to make sure mPlayState updates are reflecting the actual state of the object. 153 */ 154 private final Object mPlayStateLock = new Object(); 155 /** 156 * The listener the AudioTrack notifies previously set marker is reached. 157 * @see #setMarkerReachedListener(OnMarkerReachedListener) 158 */ 159 private OnMarkerReachedListener mMarkerListener = null; 160 /** 161 * Lock to protect marker listener updates against event notifications 162 */ 163 private final Object mMarkerListenerLock = new Object(); 164 /** 165 * The listener the AudioTrack notifies periodically during playback. 166 * @see #setPeriodicNotificationListener(OnPeriodicNotificationListener) 167 */ 168 private OnPeriodicNotificationListener mPeriodicListener = null; 169 /** 170 * Lock to protect periodic listener updates against event notifications 171 */ 172 private final Object mPeriodicListenerLock = new Object(); 173 /** 174 * Size of the native audio buffer. 175 */ 176 private int mNativeBufferSizeInBytes = 0; 177 /** 178 * Handler for events coming from the native code 179 */ 180 private NativeEventHandler mNativeEventHandler = null; 181 /** 182 * The audio data sampling rate in Hz. 183 */ 184 private int mSampleRate = 22050; 185 /** 186 * The number of input audio channels (1 is mono, 2 is stereo) 187 */ 188 private int mChannelCount = 1; 189 /** 190 * The type of the audio stream to play. See 191 * {@link AudioManager#STREAM_VOICE_CALL}, {@link AudioManager#STREAM_SYSTEM}, 192 * {@link AudioManager#STREAM_RING}, {@link AudioManager#STREAM_MUSIC} and 193 * {@link AudioManager#STREAM_ALARM} 194 */ 195 private int mStreamType = AudioManager.STREAM_MUSIC; 196 /** 197 * The way audio is consumed by the hardware, streaming or static. 198 */ 199 private int mDataLoadMode = MODE_STREAM; 200 /** 201 * The current audio channel configuration 202 */ 203 private int mChannelConfiguration = AudioFormat.CHANNEL_CONFIGURATION_MONO; 204 /** 205 * The encoding of the audio samples. 206 * @see AudioFormat#ENCODING_PCM_8BIT 207 * @see AudioFormat#ENCODING_PCM_16BIT 208 */ 209 private int mAudioFormat = AudioFormat.ENCODING_PCM_16BIT; 210 211 212 //-------------------------------- 213 // Used exclusively by native code 214 //-------------------- 215 /** 216 * Accessed by native methods: provides access to C++ AudioTrack object 217 */ 218 @SuppressWarnings("unused") 219 private int mNativeTrackInJavaObj; 220 /** 221 * Accessed by native methods: provides access to the JNI data (i.e. resources used by 222 * the native AudioTrack object, but not stored in it). 223 */ 224 @SuppressWarnings("unused") 225 private int mJniData; 226 227 228 //-------------------------------------------------------------------------- 229 // Constructor, Finalize 230 //-------------------- 231 /** 232 * Class constructor. 233 * @param streamType the type of the audio stream. See 234 235 * {@link AudioManager#STREAM_VOICE_CALL}, {@link AudioManager#STREAM_SYSTEM}, 236 * {@link AudioManager#STREAM_RING}, {@link AudioManager#STREAM_MUSIC} and 237 * {@link AudioManager#STREAM_ALARM} 238 * @param sampleRateInHz the sample rate expressed in Hertz. Examples of rates are (but 239 * not limited to) 44100, 22050 and 11025. 240 * @param channelConfig describes the configuration of the audio channels. 241 242 * See {@link AudioFormat#CHANNEL_CONFIGURATION_MONO} and 243 * {@link AudioFormat#CHANNEL_CONFIGURATION_STEREO} 244 245 * @param audioFormat the format in which the audio data is represented. 246 * See {@link AudioFormat#ENCODING_PCM_16BIT} and 247 * {@link AudioFormat#ENCODING_PCM_8BIT} 248 * @param bufferSizeInBytes the total size (in bytes) of the buffer where audio data is read 249 * from for playback. If using the AudioTrack in streaming mode, you can write data into 250 * this buffer in smaller chunks than this size. If using the AudioTrack in static mode, 251 * this is the maximum size of the sound that will be played for this instance. 252 * @param mode streaming or static buffer. See {@link #MODE_STATIC} and {@link #MODE_STREAM} 253 * @throws java.lang.IllegalArgumentException 254 */ 255 public AudioTrack(int streamType, int sampleRateInHz, int channelConfig, int audioFormat, 256 int bufferSizeInBytes, int mode) 257 throws IllegalArgumentException { 258 mState = STATE_UNINITIALIZED; 259 260 audioParamCheck(streamType, sampleRateInHz, channelConfig, audioFormat, mode); 261 262 audioBuffSizeCheck(bufferSizeInBytes); 263 264 // native initialization 265 int initResult = native_setup(new WeakReference<AudioTrack>(this), 266 mStreamType, mSampleRate, mChannelCount, mAudioFormat, 267 mNativeBufferSizeInBytes, mDataLoadMode); 268 if (initResult != SUCCESS) { 269 loge("Error code "+initResult+" when initializing AudioTrack."); 270 return; // with mState == STATE_UNINITIALIZED 271 } 272 273 if (mDataLoadMode == MODE_STATIC) { 274 mState = STATE_NO_STATIC_DATA; 275 } else { 276 mState = STATE_INITIALIZED; 277 } 278 } 279 280 281 // Convenience method for the constructor's parameter checks. 282 // This is where constructor IllegalArgumentException-s are thrown 283 // postconditions: 284 // mStreamType is valid 285 // mChannelCount is valid 286 // mAudioFormat is valid 287 // mSampleRate is valid 288 // mDataLoadMode is valid 289 private void audioParamCheck(int streamType, int sampleRateInHz, 290 int channelConfig, int audioFormat, int mode) { 291 292 //-------------- 293 // stream type 294 if( (streamType != AudioManager.STREAM_ALARM) && (streamType != AudioManager.STREAM_MUSIC) 295 && (streamType != AudioManager.STREAM_RING) && (streamType != AudioManager.STREAM_SYSTEM) 296 && (streamType != AudioManager.STREAM_VOICE_CALL) 297 && (streamType != AudioManager.STREAM_NOTIFICATION) 298 && (streamType != AudioManager.STREAM_BLUETOOTH_SCO)) { 299 throw (new IllegalArgumentException("Invalid stream type.")); 300 } else { 301 mStreamType = streamType; 302 } 303 304 //-------------- 305 // sample rate 306 if ( (sampleRateInHz < 4000) || (sampleRateInHz > 48000) ) { 307 throw (new IllegalArgumentException(sampleRateInHz 308 + "Hz is not a supported sample rate.")); 309 } else { 310 mSampleRate = sampleRateInHz; 311 } 312 313 //-------------- 314 // channel config 315 switch (channelConfig) { 316 case AudioFormat.CHANNEL_CONFIGURATION_DEFAULT: 317 case AudioFormat.CHANNEL_CONFIGURATION_MONO: 318 mChannelCount = 1; 319 mChannelConfiguration = AudioFormat.CHANNEL_CONFIGURATION_MONO; 320 break; 321 case AudioFormat.CHANNEL_CONFIGURATION_STEREO: 322 mChannelCount = 2; 323 mChannelConfiguration = AudioFormat.CHANNEL_CONFIGURATION_STEREO; 324 break; 325 default: 326 mChannelCount = 0; 327 mChannelConfiguration = AudioFormat.CHANNEL_CONFIGURATION_INVALID; 328 throw(new IllegalArgumentException("Unsupported channel configuration.")); 329 } 330 331 //-------------- 332 // audio format 333 switch (audioFormat) { 334 case AudioFormat.ENCODING_DEFAULT: 335 mAudioFormat = AudioFormat.ENCODING_PCM_16BIT; 336 break; 337 case AudioFormat.ENCODING_PCM_16BIT: 338 case AudioFormat.ENCODING_PCM_8BIT: 339 mAudioFormat = audioFormat; 340 break; 341 default: 342 mAudioFormat = AudioFormat.ENCODING_INVALID; 343 throw(new IllegalArgumentException("Unsupported sample encoding." 344 + " Should be ENCODING_PCM_8BIT or ENCODING_PCM_16BIT.")); 345 } 346 347 //-------------- 348 // audio load mode 349 if ( (mode != MODE_STREAM) && (mode != MODE_STATIC) ) { 350 throw(new IllegalArgumentException("Invalid mode.")); 351 } else { 352 mDataLoadMode = mode; 353 } 354 } 355 356 357 // Convenience method for the contructor's audio buffer size check. 358 // preconditions: 359 // mChannelCount is valid 360 // mAudioFormat is valid 361 // postcondition: 362 // mNativeBufferSizeInBytes is valid (multiple of frame size, positive) 363 private void audioBuffSizeCheck(int audioBufferSize) { 364 // NB: this section is only valid with PCM data. 365 // To update when supporting compressed formats 366 int frameSizeInBytes = mChannelCount 367 * (mAudioFormat == AudioFormat.ENCODING_PCM_8BIT ? 1 : 2); 368 if ((audioBufferSize % frameSizeInBytes != 0) || (audioBufferSize < 1)) { 369 throw (new IllegalArgumentException("Invalid audio buffer size.")); 370 } 371 372 mNativeBufferSizeInBytes = audioBufferSize; 373 } 374 375 376 // Convenience method for the creation of the native event handler 377 // It is called only when a non-null event listener is set. 378 // precondition: 379 // mNativeEventHandler is null 380 private void createNativeEventHandler() { 381 Looper looper; 382 if ((looper = Looper.myLooper()) != null) { 383 mNativeEventHandler = new NativeEventHandler(this, looper); 384 } else if ((looper = Looper.getMainLooper()) != null) { 385 mNativeEventHandler = new NativeEventHandler(this, looper); 386 } else { 387 mNativeEventHandler = null; 388 } 389 } 390 391 392 /** 393 * Releases the native AudioTrack resources. 394 */ 395 public void release() { 396 // even though native_release() stops the native AudioTrack, we need to stop 397 // AudioTrack subclasses too. 398 stop(); 399 native_release(); 400 mState = STATE_UNINITIALIZED; 401 } 402 403 @Override 404 protected void finalize() { 405 native_finalize(); 406 } 407 408 //-------------------------------------------------------------------------- 409 // Getters 410 //-------------------- 411 /** 412 * Returns the minimum valid volume value. Volume values set under this one will 413 * be clamped at this value. 414 * @return the minimum volume expressed as a linear attenuation. 415 */ 416 static public float getMinVolume() { 417 return AudioTrack.VOLUME_MIN; 418 } 419 420 /** 421 * Returns the maximum valid volume value. Volume values set above this one will 422 * be clamped at this value. 423 * @return the maximum volume expressed as a linear attenuation. 424 */ 425 static public float getMaxVolume() { 426 return AudioTrack.VOLUME_MAX; 427 } 428 429 /** 430 * Returns the configured audio data sample rate in Hz 431 */ 432 public int getSampleRate() { 433 return mSampleRate; 434 } 435 436 /** 437 * Returns the configured audio data format. See {@link AudioFormat#ENCODING_PCM_16BIT} 438 * and {@link AudioFormat#ENCODING_PCM_8BIT}. 439 */ 440 public int getAudioFormat() { 441 return mAudioFormat; 442 } 443 444 /** 445 * Returns the type of audio stream this AudioTrack is configured for. 446 * Compare the result against {@link AudioManager#STREAM_VOICE_CALL}, 447 * {@link AudioManager#STREAM_SYSTEM}, {@link AudioManager#STREAM_RING}, 448 * {@link AudioManager#STREAM_MUSIC} or {@link AudioManager#STREAM_ALARM} 449 */ 450 public int getStreamType() { 451 return mStreamType; 452 } 453 454 /** 455 * Returns the configured channel configuration. 456 457 * See {@link AudioFormat#CHANNEL_CONFIGURATION_MONO} 458 * and {@link AudioFormat#CHANNEL_CONFIGURATION_STEREO}. 459 */ 460 public int getChannelConfiguration() { 461 return mChannelConfiguration; 462 } 463 464 /** 465 * Returns the configured number of channels. 466 */ 467 public int getChannelCount() { 468 return mChannelCount; 469 } 470 471 /** 472 * Returns the state of the AudioTrack instance. This is useful after the 473 * AudioTrack instance has been created to check if it was initialized 474 * properly. This ensures that the appropriate hardware resources have been 475 * acquired. 476 */ 477 public int getState() { 478 return mState; 479 } 480 481 /** 482 * Returns the playback state of the AudioTrack instance. 483 * @see #PLAYSTATE_STOPPED 484 * @see #PLAYSTATE_PAUSED 485 * @see #PLAYSTATE_PLAYING 486 */ 487 public int getPlayState() { 488 return mPlayState; 489 } 490 491 /** 492 * Returns the native frame count used by the hardware 493 */ 494 protected int getNativeFrameCount() { 495 return native_get_native_frame_count(); 496 } 497 498 /** 499 * @return marker position in frames 500 */ 501 public int getNotificationMarkerPosition() { 502 return native_get_marker_pos(); 503 } 504 505 /** 506 * @return update period in frames 507 */ 508 public int getPositionNotificationPeriod() { 509 return native_get_pos_update_period(); 510 } 511 512 /** 513 * @return playback head position in frames 514 */ 515 public int getPlaybackHeadPosition() { 516 return native_get_position(); 517 } 518 519 /** 520 * Returns the hardware output sample rate 521 */ 522 static public int getNativeOutputSampleRate() { 523 return native_get_output_sample_rate(); 524 } 525 526 /** 527 * {@hide} 528 * Returns the minimum buffer size required for the successful creation of an AudioTrack 529 * object to be created in the {@link #MODE_STREAM} mode. 530 * @param sampleRateInHz the sample rate expressed in Hertz. 531 * @param channelConfig describes the configuration of the audio channels. 532 * See {@link AudioFormat#CHANNEL_CONFIGURATION_MONO} and 533 * {@link AudioFormat#CHANNEL_CONFIGURATION_STEREO} 534 * @param audioFormat the format in which the audio data is represented. 535 * See {@link AudioFormat#ENCODING_PCM_16BIT} and 536 * {@link AudioFormat#ENCODING_PCM_8BIT} 537 * @return -1 if an invalid parameter was passed or if the implementation was unable to 538 * query the hardware for its output properties, or the minimum buffer size expressed 539 * in number of bytes. 540 */ 541 static public int getMinBufferSize(int sampleRateInHz, int channelConfig, int audioFormat) { 542 int channelCount = 0; 543 switch(channelConfig) { 544 case AudioFormat.CHANNEL_CONFIGURATION_MONO: 545 channelCount = 1; 546 break; 547 case AudioFormat.CHANNEL_CONFIGURATION_STEREO: 548 channelCount = 2; 549 break; 550 default: 551 loge("getMinBufferSize(): Invalid channel configuration."); 552 return -1; 553 } 554 555 if ((audioFormat != AudioFormat.ENCODING_PCM_16BIT) 556 && (audioFormat != AudioFormat.ENCODING_PCM_8BIT)) { 557 loge("getMinBufferSize(): Invalid audio format."); 558 return -1; 559 } 560 561 return native_get_min_buff_size(sampleRateInHz, channelCount, audioFormat); 562 } 563 564 565 //-------------------------------------------------------------------------- 566 // Initialization / configuration 567 //-------------------- 568 /** 569 * Sets the listener the AudioTrack notifies when a previously set marker is reached. 570 * @param listener 571 */ 572 public void setMarkerReachedListener(OnMarkerReachedListener listener) { 573 synchronized (mMarkerListenerLock) { 574 mMarkerListener = listener; 575 } 576 if ((listener != null) && (mNativeEventHandler == null)) { 577 createNativeEventHandler(); 578 } 579 } 580 581 582 /** 583 * Sets the listener the AudioTrack notifies periodically during playback. 584 * @param listener 585 */ 586 public void setPeriodicNotificationListener(OnPeriodicNotificationListener listener) { 587 synchronized (mPeriodicListenerLock) { 588 mPeriodicListener = listener; 589 } 590 if ((listener != null) && (mNativeEventHandler == null)) { 591 createNativeEventHandler(); 592 } 593 } 594 595 596 /** 597 * Sets the specified left/right output volume values on the AudioTrack. Values are clamped 598 * to the ({@link #getMinVolume()}, {@link #getMaxVolume()}) interval if outside this range. 599 * @param leftVolume output attenuation for the left channel. A value of 0.0f is silence, 600 * a value of 1.0f is no attenuation. 601 * @param rightVolume output attenuation for the right channel 602 * @return error code or success, see {@link #SUCCESS}, 603 * {@link #ERROR_INVALID_OPERATION} 604 */ 605 public int setStereoVolume(float leftVolume, float rightVolume) { 606 if (mState != STATE_INITIALIZED) { 607 return ERROR_INVALID_OPERATION; 608 } 609 610 // clamp the volumes 611 if (leftVolume < getMinVolume()) { 612 leftVolume = getMinVolume(); 613 } 614 if (leftVolume > getMaxVolume()) { 615 leftVolume = getMaxVolume(); 616 } 617 if (rightVolume < getMinVolume()) { 618 rightVolume = getMinVolume(); 619 } 620 if (rightVolume > getMaxVolume()) { 621 rightVolume = getMaxVolume(); 622 } 623 624 native_setVolume(leftVolume, rightVolume); 625 626 return SUCCESS; 627 } 628 629 630 /** 631 * Sets the playback sample rate for this track. This sets the sampling rate at which 632 * the audio data will be consumed and played back, not the original sampling rate of the 633 * content. Setting it to half the sample rate of the content will cause the playback to 634 * last twice as long, but will also result result in a negative pitch shift. 635 * The current implementation supports a maximum sample rate of twice the hardware output 636 * sample rate (see {@link #getNativeOutputSampleRate()}). Use {@link #getSampleRate()} to 637 * check the rate actually used in hardware after potential clamping. 638 * @param sampleRateInHz 639 * @return error code or success, see {@link #SUCCESS}, 640 * {@link #ERROR_INVALID_OPERATION} 641 */ 642 public int setPlaybackRate(int sampleRateInHz) { 643 if (mState != STATE_INITIALIZED) { 644 return ERROR_INVALID_OPERATION; 645 } 646 native_set_playback_rate(sampleRateInHz); 647 return SUCCESS; 648 } 649 650 651 /** 652 * 653 * @param markerInFrames marker in frames 654 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 655 * {@link #ERROR_INVALID_OPERATION} 656 */ 657 public int setNotificationMarkerPosition(int markerInFrames) { 658 if (mState != STATE_INITIALIZED) { 659 return ERROR_INVALID_OPERATION; 660 } 661 return native_set_marker_pos(markerInFrames); 662 } 663 664 665 /** 666 * @param periodInFrames update period in frames 667 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_INVALID_OPERATION} 668 */ 669 public int setPositionNotificationPeriod(int periodInFrames) { 670 if (mState != STATE_INITIALIZED) { 671 return ERROR_INVALID_OPERATION; 672 } 673 return native_set_pos_update_period(periodInFrames); 674 } 675 676 677 /** 678 * Sets the playback head position. The track must be stopped for the position to be changed. 679 * @param positionInFrames playback head position in frames 680 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 681 * {@link #ERROR_INVALID_OPERATION} 682 */ 683 public int setPlaybackHeadPosition(int positionInFrames) { 684 synchronized(mPlayStateLock) { 685 if(mPlayState == PLAYSTATE_STOPPED) { 686 return native_set_position(positionInFrames); 687 } else { 688 return ERROR_INVALID_OPERATION; 689 } 690 } 691 } 692 693 /** 694 * Sets the loop points and the loop count. The loop can be infinite. 695 * @param startInFrames loop start marker in frames 696 * @param endInFrames loop end marker in frames 697 * @param loopCount the number of times the loop is looped. 698 * A value of -1 means infinite looping. 699 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 700 * {@link #ERROR_INVALID_OPERATION} 701 */ 702 public int setLoopPoints(int startInFrames, int endInFrames, int loopCount) { 703 return native_set_loop(startInFrames, endInFrames, loopCount); 704 } 705 706 /** 707 * Sets the initialization state of the instance. To be used in an AudioTrack subclass 708 * constructor to set a subclass-specific post-initialization state. 709 * @param state the state of the AudioTrack instance 710 */ 711 protected void setState(int state) { 712 mState = state; 713 } 714 715 716 //--------------------------------------------------------- 717 // Transport control methods 718 //-------------------- 719 /** 720 * Starts playing an AudioTrack. 721 * @throws IllegalStateException 722 */ 723 public void play() 724 throws IllegalStateException { 725 if (mState != STATE_INITIALIZED) { 726 throw(new IllegalStateException("play() called on uninitialized AudioTrack.")); 727 } 728 729 synchronized(mPlayStateLock) { 730 native_start(); 731 mPlayState = PLAYSTATE_PLAYING; 732 } 733 } 734 735 /** 736 * Stops playing the audio data. 737 * @throws IllegalStateException 738 */ 739 public void stop() 740 throws IllegalStateException { 741 if (mState != STATE_INITIALIZED) { 742 throw(new IllegalStateException("stop() called on uninitialized AudioTrack.")); 743 } 744 745 // stop playing 746 synchronized(mPlayStateLock) { 747 native_stop(); 748 mPlayState = PLAYSTATE_STOPPED; 749 } 750 } 751 752 /** 753 * Pauses the playback of the audio data. 754 * @throws IllegalStateException 755 */ 756 public void pause() 757 throws IllegalStateException { 758 if (mState != STATE_INITIALIZED) { 759 throw(new IllegalStateException("pause() called on uninitialized AudioTrack.")); 760 } 761 //logd("pause()"); 762 763 // pause playback 764 synchronized(mPlayStateLock) { 765 native_pause(); 766 mPlayState = PLAYSTATE_PAUSED; 767 } 768 } 769 770 771 //--------------------------------------------------------- 772 // Audio data supply 773 //-------------------- 774 775 /** 776 * Flushes the audio data currently queued for playback. 777 */ 778 779 public void flush() { 780 if (mState == STATE_INITIALIZED) { 781 // flush the data in native layer 782 native_flush(); 783 } 784 785 } 786 787 /** 788 * Writes the audio data to the audio hardware for playback. 789 * @param audioData the array that holds the data to play. 790 * @param offsetInBytes the offset in audioData where the data to play starts. 791 * @param sizeInBytes the number of bytes to read in audioData after the offset. 792 * @return the number of bytes that were written or -1 if the object wasn't properly 793 * initialized. 794 */ 795 796 public int write(byte[] audioData,int offsetInBytes, int sizeInBytes) { 797 if ((mDataLoadMode == MODE_STATIC) 798 && (mState == STATE_NO_STATIC_DATA) 799 && (sizeInBytes > 0)) { 800 mState = STATE_INITIALIZED; 801 } 802 //TODO check if future writes should be forbidden for static tracks 803 // or: how to update data for static tracks? 804 805 if (mState != STATE_INITIALIZED) { 806 return -1; 807 } 808 809 return native_write_byte(audioData, offsetInBytes, sizeInBytes); 810 } 811 812 813 /** 814 * Writes the audio data to the audio hardware for playback. 815 * @param audioData the array that holds the data to play. 816 * @param offsetInShorts the offset in audioData where the data to play starts. 817 * @param sizeInShorts the number of bytes to read in audioData after the offset. 818 * @return the number of shorts that were written or -1 if the object wasn't properly 819 * initialized. 820 */ 821 822 public int write(short[] audioData, int offsetInShorts, int sizeInShorts) { 823 if ((mDataLoadMode == MODE_STATIC) 824 && (mState == STATE_NO_STATIC_DATA) 825 && (sizeInShorts > 0)) { 826 mState = STATE_INITIALIZED; 827 } 828 //TODO check if future writes should be forbidden for static tracks 829 // or: how to update data for static tracks? 830 831 if (mState != STATE_INITIALIZED) { 832 return -1; 833 } 834 835 return native_write_short(audioData, offsetInShorts, sizeInShorts); 836 } 837 838 839 /** 840 * Notifies the native resource to reuse the audio data already loaded in the native 841 * layer. This call is only valid with AudioTrack instances that don't use the streaming 842 * model. 843 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 844 * {@link #ERROR_INVALID_OPERATION} 845 */ 846 public int reloadStaticData() { 847 if (mDataLoadMode == MODE_STREAM) { 848 return ERROR_INVALID_OPERATION; 849 } 850 return native_reload_static(); 851 } 852 853 854 //--------------------------------------------------------- 855 // Interface definitions 856 //-------------------- 857 /** 858 * Interface definition for a callback to be invoked when an AudioTrack has 859 * reached a notification marker set by setNotificationMarkerPosition(). 860 */ 861 public interface OnMarkerReachedListener { 862 /** 863 * Called on the listener to notify it that the previously set marker has been reached 864 * by the playback head. 865 */ 866 void onMarkerReached(AudioTrack track); 867 } 868 869 870 /** 871 * Interface definition for a callback to be invoked for each periodic AudioTrack 872 * update during playback. The update interval is set by setPositionNotificationPeriod(). 873 */ 874 public interface OnPeriodicNotificationListener { 875 /** 876 * Called on the listener to periodically notify it that the playback head has reached 877 * a multiple of the notification period. 878 */ 879 void onPeriodicNotification(AudioTrack track); 880 } 881 882 883 //--------------------------------------------------------- 884 // Inner classes 885 //-------------------- 886 /** 887 * Helper class to handle the forwarding of native events to the appropriate listeners 888 */ 889 private class NativeEventHandler extends Handler 890 { 891 private AudioTrack mAudioTrack; 892 893 public NativeEventHandler(AudioTrack mp, Looper looper) { 894 super(looper); 895 mAudioTrack = mp; 896 } 897 898 @Override 899 public void handleMessage(Message msg) { 900 if (mAudioTrack == null) { 901 return; 902 } 903 switch(msg.what) { 904 case NATIVE_EVENT_MARKER: 905 synchronized (mMarkerListenerLock) { 906 if (mAudioTrack.mMarkerListener != null) { 907 mAudioTrack.mMarkerListener.onMarkerReached(mAudioTrack); 908 } 909 } 910 break; 911 case NATIVE_EVENT_NEW_POS: 912 synchronized (mPeriodicListenerLock) { 913 if (mAudioTrack.mPeriodicListener != null) { 914 mAudioTrack.mPeriodicListener.onPeriodicNotification(mAudioTrack); 915 } 916 } 917 break; 918 default: 919 Log.e(TAG, "[ android.media.AudioTrack.NativeEventHandler ] " + 920 "Unknown event type: " + msg.what); 921 break; 922 } 923 } 924 } 925 926 927 //--------------------------------------------------------- 928 // Java methods called from the native side 929 //-------------------- 930 @SuppressWarnings("unused") 931 private static void postEventFromNative(Object audiotrack_ref, 932 int what, int arg1, int arg2, Object obj) { 933 //logd("Event posted from the native side: event="+ what + " args="+ arg1+" "+arg2); 934 AudioTrack track = (AudioTrack)((WeakReference)audiotrack_ref).get(); 935 if (track == null) { 936 return; 937 } 938 939 if (track.mNativeEventHandler != null) { 940 Message m = track.mNativeEventHandler.obtainMessage(what, arg1, arg2, obj); 941 track.mNativeEventHandler.sendMessage(m); 942 } 943 944 } 945 946 947 //--------------------------------------------------------- 948 // Native methods called from the Java side 949 //-------------------- 950 951 private native final int native_setup(Object audiotrack_this, 952 int streamType, int sampleRate, int nbChannels, int audioFormat, 953 int buffSizeInBytes, int mode); 954 955 private native final void native_finalize(); 956 957 private native final void native_release(); 958 959 private native final void native_start(); 960 961 private native final void native_stop(); 962 963 private native final void native_pause(); 964 965 private native final void native_flush(); 966 967 private native final int native_write_byte(byte[] audioData, 968 int offsetInBytes, int sizeInBytes); 969 970 private native final int native_write_short(short[] audioData, 971 int offsetInShorts, int sizeInShorts); 972 973 private native final int native_reload_static(); 974 975 private native final int native_get_native_frame_count(); 976 977 private native final void native_setVolume(float leftVolume, float rightVolume); 978 979 private native final void native_set_playback_rate(int sampleRateInHz); 980 private native final int native_get_playback_rate(); 981 982 private native final int native_set_marker_pos(int marker); 983 private native final int native_get_marker_pos(); 984 985 private native final int native_set_pos_update_period(int updatePeriod); 986 private native final int native_get_pos_update_period(); 987 988 private native final int native_set_position(int position); 989 private native final int native_get_position(); 990 991 private native final int native_set_loop(int start, int end, int loopCount); 992 993 static private native final int native_get_output_sample_rate(); 994 static private native final int native_get_min_buff_size( 995 int sampleRateInHz, int channelConfig, int audioFormat); 996 997 998 //--------------------------------------------------------- 999 // Utility methods 1000 //------------------ 1001 1002 private static void logd(String msg) { 1003 Log.d(TAG, "[ android.media.AudioTrack ] " + msg); 1004 } 1005 1006 private static void loge(String msg) { 1007 Log.e(TAG, "[ android.media.AudioTrack ] " + msg); 1008 } 1009 1010}