AudioTrack.java revision da996f390e17e16f2dfa60e972e7ebc4f868f37e
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 try { 399 stop(); 400 } catch(IllegalStateException ise) { 401 // don't raise an exception, we're releasing the resources. 402 } 403 native_release(); 404 mState = STATE_UNINITIALIZED; 405 } 406 407 @Override 408 protected void finalize() { 409 native_finalize(); 410 } 411 412 //-------------------------------------------------------------------------- 413 // Getters 414 //-------------------- 415 /** 416 * Returns the minimum valid volume value. Volume values set under this one will 417 * be clamped at this value. 418 * @return the minimum volume expressed as a linear attenuation. 419 */ 420 static public float getMinVolume() { 421 return AudioTrack.VOLUME_MIN; 422 } 423 424 /** 425 * Returns the maximum valid volume value. Volume values set above this one will 426 * be clamped at this value. 427 * @return the maximum volume expressed as a linear attenuation. 428 */ 429 static public float getMaxVolume() { 430 return AudioTrack.VOLUME_MAX; 431 } 432 433 /** 434 * Returns the configured audio data sample rate in Hz 435 */ 436 public int getSampleRate() { 437 return mSampleRate; 438 } 439 440 /** 441 * Returns the configured audio data format. See {@link AudioFormat#ENCODING_PCM_16BIT} 442 * and {@link AudioFormat#ENCODING_PCM_8BIT}. 443 */ 444 public int getAudioFormat() { 445 return mAudioFormat; 446 } 447 448 /** 449 * Returns the type of audio stream this AudioTrack is configured for. 450 * Compare the result against {@link AudioManager#STREAM_VOICE_CALL}, 451 * {@link AudioManager#STREAM_SYSTEM}, {@link AudioManager#STREAM_RING}, 452 * {@link AudioManager#STREAM_MUSIC} or {@link AudioManager#STREAM_ALARM} 453 */ 454 public int getStreamType() { 455 return mStreamType; 456 } 457 458 /** 459 * Returns the configured channel configuration. 460 461 * See {@link AudioFormat#CHANNEL_CONFIGURATION_MONO} 462 * and {@link AudioFormat#CHANNEL_CONFIGURATION_STEREO}. 463 */ 464 public int getChannelConfiguration() { 465 return mChannelConfiguration; 466 } 467 468 /** 469 * Returns the configured number of channels. 470 */ 471 public int getChannelCount() { 472 return mChannelCount; 473 } 474 475 /** 476 * Returns the state of the AudioTrack instance. This is useful after the 477 * AudioTrack instance has been created to check if it was initialized 478 * properly. This ensures that the appropriate hardware resources have been 479 * acquired. 480 */ 481 public int getState() { 482 return mState; 483 } 484 485 /** 486 * Returns the playback state of the AudioTrack instance. 487 * @see #PLAYSTATE_STOPPED 488 * @see #PLAYSTATE_PAUSED 489 * @see #PLAYSTATE_PLAYING 490 */ 491 public int getPlayState() { 492 return mPlayState; 493 } 494 495 /** 496 * Returns the native frame count used by the hardware 497 */ 498 protected int getNativeFrameCount() { 499 return native_get_native_frame_count(); 500 } 501 502 /** 503 * @return marker position in frames 504 */ 505 public int getNotificationMarkerPosition() { 506 return native_get_marker_pos(); 507 } 508 509 /** 510 * @return update period in frames 511 */ 512 public int getPositionNotificationPeriod() { 513 return native_get_pos_update_period(); 514 } 515 516 /** 517 * @return playback head position in frames 518 */ 519 public int getPlaybackHeadPosition() { 520 return native_get_position(); 521 } 522 523 /** 524 * Returns the hardware output sample rate 525 */ 526 static public int getNativeOutputSampleRate() { 527 return native_get_output_sample_rate(); 528 } 529 530 /** 531 * {@hide} 532 * Returns the minimum buffer size required for the successful creation of an AudioTrack 533 * object to be created in the {@link #MODE_STREAM} mode. 534 * @param sampleRateInHz the sample rate expressed in Hertz. 535 * @param channelConfig describes the configuration of the audio channels. 536 * See {@link AudioFormat#CHANNEL_CONFIGURATION_MONO} and 537 * {@link AudioFormat#CHANNEL_CONFIGURATION_STEREO} 538 * @param audioFormat the format in which the audio data is represented. 539 * See {@link AudioFormat#ENCODING_PCM_16BIT} and 540 * {@link AudioFormat#ENCODING_PCM_8BIT} 541 * @return -1 if an invalid parameter was passed or if the implementation was unable to 542 * query the hardware for its output properties, or the minimum buffer size expressed 543 * in number of bytes. 544 */ 545 static public int getMinBufferSize(int sampleRateInHz, int channelConfig, int audioFormat) { 546 int channelCount = 0; 547 switch(channelConfig) { 548 case AudioFormat.CHANNEL_CONFIGURATION_MONO: 549 channelCount = 1; 550 break; 551 case AudioFormat.CHANNEL_CONFIGURATION_STEREO: 552 channelCount = 2; 553 break; 554 default: 555 loge("getMinBufferSize(): Invalid channel configuration."); 556 return -1; 557 } 558 559 if ((audioFormat != AudioFormat.ENCODING_PCM_16BIT) 560 && (audioFormat != AudioFormat.ENCODING_PCM_8BIT)) { 561 loge("getMinBufferSize(): Invalid audio format."); 562 return -1; 563 } 564 565 return native_get_min_buff_size(sampleRateInHz, channelCount, audioFormat); 566 } 567 568 569 //-------------------------------------------------------------------------- 570 // Initialization / configuration 571 //-------------------- 572 /** 573 * Sets the listener the AudioTrack notifies when a previously set marker is reached. 574 * @param listener 575 */ 576 public void setMarkerReachedListener(OnMarkerReachedListener listener) { 577 synchronized (mMarkerListenerLock) { 578 mMarkerListener = listener; 579 } 580 if ((listener != null) && (mNativeEventHandler == null)) { 581 createNativeEventHandler(); 582 } 583 } 584 585 586 /** 587 * Sets the listener the AudioTrack notifies periodically during playback. 588 * @param listener 589 */ 590 public void setPeriodicNotificationListener(OnPeriodicNotificationListener listener) { 591 synchronized (mPeriodicListenerLock) { 592 mPeriodicListener = listener; 593 } 594 if ((listener != null) && (mNativeEventHandler == null)) { 595 createNativeEventHandler(); 596 } 597 } 598 599 600 /** 601 * Sets the specified left/right output volume values on the AudioTrack. Values are clamped 602 * to the ({@link #getMinVolume()}, {@link #getMaxVolume()}) interval if outside this range. 603 * @param leftVolume output attenuation for the left channel. A value of 0.0f is silence, 604 * a value of 1.0f is no attenuation. 605 * @param rightVolume output attenuation for the right channel 606 * @return error code or success, see {@link #SUCCESS}, 607 * {@link #ERROR_INVALID_OPERATION} 608 */ 609 public int setStereoVolume(float leftVolume, float rightVolume) { 610 if (mState != STATE_INITIALIZED) { 611 return ERROR_INVALID_OPERATION; 612 } 613 614 // clamp the volumes 615 if (leftVolume < getMinVolume()) { 616 leftVolume = getMinVolume(); 617 } 618 if (leftVolume > getMaxVolume()) { 619 leftVolume = getMaxVolume(); 620 } 621 if (rightVolume < getMinVolume()) { 622 rightVolume = getMinVolume(); 623 } 624 if (rightVolume > getMaxVolume()) { 625 rightVolume = getMaxVolume(); 626 } 627 628 native_setVolume(leftVolume, rightVolume); 629 630 return SUCCESS; 631 } 632 633 634 /** 635 * Sets the playback sample rate for this track. This sets the sampling rate at which 636 * the audio data will be consumed and played back, not the original sampling rate of the 637 * content. Setting it to half the sample rate of the content will cause the playback to 638 * last twice as long, but will also result result in a negative pitch shift. 639 * The current implementation supports a maximum sample rate of twice the hardware output 640 * sample rate (see {@link #getNativeOutputSampleRate()}). Use {@link #getSampleRate()} to 641 * check the rate actually used in hardware after potential clamping. 642 * @param sampleRateInHz 643 * @return error code or success, see {@link #SUCCESS}, 644 * {@link #ERROR_INVALID_OPERATION} 645 */ 646 public int setPlaybackRate(int sampleRateInHz) { 647 if (mState != STATE_INITIALIZED) { 648 return ERROR_INVALID_OPERATION; 649 } 650 native_set_playback_rate(sampleRateInHz); 651 return SUCCESS; 652 } 653 654 655 /** 656 * 657 * @param markerInFrames marker in frames 658 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 659 * {@link #ERROR_INVALID_OPERATION} 660 */ 661 public int setNotificationMarkerPosition(int markerInFrames) { 662 if (mState != STATE_INITIALIZED) { 663 return ERROR_INVALID_OPERATION; 664 } 665 return native_set_marker_pos(markerInFrames); 666 } 667 668 669 /** 670 * @param periodInFrames update period in frames 671 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_INVALID_OPERATION} 672 */ 673 public int setPositionNotificationPeriod(int periodInFrames) { 674 if (mState != STATE_INITIALIZED) { 675 return ERROR_INVALID_OPERATION; 676 } 677 return native_set_pos_update_period(periodInFrames); 678 } 679 680 681 /** 682 * Sets the playback head position. The track must be stopped for the position to be changed. 683 * @param positionInFrames playback head position in frames 684 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 685 * {@link #ERROR_INVALID_OPERATION} 686 */ 687 public int setPlaybackHeadPosition(int positionInFrames) { 688 synchronized(mPlayStateLock) { 689 if(mPlayState == PLAYSTATE_STOPPED) { 690 return native_set_position(positionInFrames); 691 } else { 692 return ERROR_INVALID_OPERATION; 693 } 694 } 695 } 696 697 /** 698 * Sets the loop points and the loop count. The loop can be infinite. 699 * @param startInFrames loop start marker in frames 700 * @param endInFrames loop end marker in frames 701 * @param loopCount the number of times the loop is looped. 702 * A value of -1 means infinite looping. 703 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 704 * {@link #ERROR_INVALID_OPERATION} 705 */ 706 public int setLoopPoints(int startInFrames, int endInFrames, int loopCount) { 707 return native_set_loop(startInFrames, endInFrames, loopCount); 708 } 709 710 /** 711 * Sets the initialization state of the instance. To be used in an AudioTrack subclass 712 * constructor to set a subclass-specific post-initialization state. 713 * @param state the state of the AudioTrack instance 714 */ 715 protected void setState(int state) { 716 mState = state; 717 } 718 719 720 //--------------------------------------------------------- 721 // Transport control methods 722 //-------------------- 723 /** 724 * Starts playing an AudioTrack. 725 * @throws IllegalStateException 726 */ 727 public void play() 728 throws IllegalStateException { 729 if (mState != STATE_INITIALIZED) { 730 throw(new IllegalStateException("play() called on uninitialized AudioTrack.")); 731 } 732 733 synchronized(mPlayStateLock) { 734 native_start(); 735 mPlayState = PLAYSTATE_PLAYING; 736 } 737 } 738 739 /** 740 * Stops playing the audio data. 741 * @throws IllegalStateException 742 */ 743 public void stop() 744 throws IllegalStateException { 745 if (mState != STATE_INITIALIZED) { 746 throw(new IllegalStateException("stop() called on uninitialized AudioTrack.")); 747 } 748 749 // stop playing 750 synchronized(mPlayStateLock) { 751 native_stop(); 752 mPlayState = PLAYSTATE_STOPPED; 753 } 754 } 755 756 /** 757 * Pauses the playback of the audio data. 758 * @throws IllegalStateException 759 */ 760 public void pause() 761 throws IllegalStateException { 762 if (mState != STATE_INITIALIZED) { 763 throw(new IllegalStateException("pause() called on uninitialized AudioTrack.")); 764 } 765 //logd("pause()"); 766 767 // pause playback 768 synchronized(mPlayStateLock) { 769 native_pause(); 770 mPlayState = PLAYSTATE_PAUSED; 771 } 772 } 773 774 775 //--------------------------------------------------------- 776 // Audio data supply 777 //-------------------- 778 779 /** 780 * Flushes the audio data currently queued for playback. 781 */ 782 783 public void flush() { 784 if (mState == STATE_INITIALIZED) { 785 // flush the data in native layer 786 native_flush(); 787 } 788 789 } 790 791 /** 792 * Writes the audio data to the audio hardware for playback. 793 * @param audioData the array that holds the data to play. 794 * @param offsetInBytes the offset in audioData where the data to play starts. 795 * @param sizeInBytes the number of bytes to read in audioData after the offset. 796 * @return the number of bytes that were written or -1 if the object wasn't properly 797 * initialized. 798 */ 799 800 public int write(byte[] audioData,int offsetInBytes, int sizeInBytes) { 801 if ((mDataLoadMode == MODE_STATIC) 802 && (mState == STATE_NO_STATIC_DATA) 803 && (sizeInBytes > 0)) { 804 mState = STATE_INITIALIZED; 805 } 806 //TODO check if future writes should be forbidden for static tracks 807 // or: how to update data for static tracks? 808 809 if (mState != STATE_INITIALIZED) { 810 return -1; 811 } 812 813 return native_write_byte(audioData, offsetInBytes, sizeInBytes); 814 } 815 816 817 /** 818 * Writes the audio data to the audio hardware for playback. 819 * @param audioData the array that holds the data to play. 820 * @param offsetInShorts the offset in audioData where the data to play starts. 821 * @param sizeInShorts the number of bytes to read in audioData after the offset. 822 * @return the number of shorts that were written or -1 if the object wasn't properly 823 * initialized. 824 */ 825 826 public int write(short[] audioData, int offsetInShorts, int sizeInShorts) { 827 if ((mDataLoadMode == MODE_STATIC) 828 && (mState == STATE_NO_STATIC_DATA) 829 && (sizeInShorts > 0)) { 830 mState = STATE_INITIALIZED; 831 } 832 //TODO check if future writes should be forbidden for static tracks 833 // or: how to update data for static tracks? 834 835 if (mState != STATE_INITIALIZED) { 836 return -1; 837 } 838 839 return native_write_short(audioData, offsetInShorts, sizeInShorts); 840 } 841 842 843 /** 844 * Notifies the native resource to reuse the audio data already loaded in the native 845 * layer. This call is only valid with AudioTrack instances that don't use the streaming 846 * model. 847 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 848 * {@link #ERROR_INVALID_OPERATION} 849 */ 850 public int reloadStaticData() { 851 if (mDataLoadMode == MODE_STREAM) { 852 return ERROR_INVALID_OPERATION; 853 } 854 return native_reload_static(); 855 } 856 857 858 //--------------------------------------------------------- 859 // Interface definitions 860 //-------------------- 861 /** 862 * Interface definition for a callback to be invoked when an AudioTrack has 863 * reached a notification marker set by setNotificationMarkerPosition(). 864 */ 865 public interface OnMarkerReachedListener { 866 /** 867 * Called on the listener to notify it that the previously set marker has been reached 868 * by the playback head. 869 */ 870 void onMarkerReached(AudioTrack track); 871 } 872 873 874 /** 875 * Interface definition for a callback to be invoked for each periodic AudioTrack 876 * update during playback. The update interval is set by setPositionNotificationPeriod(). 877 */ 878 public interface OnPeriodicNotificationListener { 879 /** 880 * Called on the listener to periodically notify it that the playback head has reached 881 * a multiple of the notification period. 882 */ 883 void onPeriodicNotification(AudioTrack track); 884 } 885 886 887 //--------------------------------------------------------- 888 // Inner classes 889 //-------------------- 890 /** 891 * Helper class to handle the forwarding of native events to the appropriate listeners 892 */ 893 private class NativeEventHandler extends Handler 894 { 895 private AudioTrack mAudioTrack; 896 897 public NativeEventHandler(AudioTrack mp, Looper looper) { 898 super(looper); 899 mAudioTrack = mp; 900 } 901 902 @Override 903 public void handleMessage(Message msg) { 904 if (mAudioTrack == null) { 905 return; 906 } 907 switch(msg.what) { 908 case NATIVE_EVENT_MARKER: 909 synchronized (mMarkerListenerLock) { 910 if (mAudioTrack.mMarkerListener != null) { 911 mAudioTrack.mMarkerListener.onMarkerReached(mAudioTrack); 912 } 913 } 914 break; 915 case NATIVE_EVENT_NEW_POS: 916 synchronized (mPeriodicListenerLock) { 917 if (mAudioTrack.mPeriodicListener != null) { 918 mAudioTrack.mPeriodicListener.onPeriodicNotification(mAudioTrack); 919 } 920 } 921 break; 922 default: 923 Log.e(TAG, "[ android.media.AudioTrack.NativeEventHandler ] " + 924 "Unknown event type: " + msg.what); 925 break; 926 } 927 } 928 } 929 930 931 //--------------------------------------------------------- 932 // Java methods called from the native side 933 //-------------------- 934 @SuppressWarnings("unused") 935 private static void postEventFromNative(Object audiotrack_ref, 936 int what, int arg1, int arg2, Object obj) { 937 //logd("Event posted from the native side: event="+ what + " args="+ arg1+" "+arg2); 938 AudioTrack track = (AudioTrack)((WeakReference)audiotrack_ref).get(); 939 if (track == null) { 940 return; 941 } 942 943 if (track.mNativeEventHandler != null) { 944 Message m = track.mNativeEventHandler.obtainMessage(what, arg1, arg2, obj); 945 track.mNativeEventHandler.sendMessage(m); 946 } 947 948 } 949 950 951 //--------------------------------------------------------- 952 // Native methods called from the Java side 953 //-------------------- 954 955 private native final int native_setup(Object audiotrack_this, 956 int streamType, int sampleRate, int nbChannels, int audioFormat, 957 int buffSizeInBytes, int mode); 958 959 private native final void native_finalize(); 960 961 private native final void native_release(); 962 963 private native final void native_start(); 964 965 private native final void native_stop(); 966 967 private native final void native_pause(); 968 969 private native final void native_flush(); 970 971 private native final int native_write_byte(byte[] audioData, 972 int offsetInBytes, int sizeInBytes); 973 974 private native final int native_write_short(short[] audioData, 975 int offsetInShorts, int sizeInShorts); 976 977 private native final int native_reload_static(); 978 979 private native final int native_get_native_frame_count(); 980 981 private native final void native_setVolume(float leftVolume, float rightVolume); 982 983 private native final void native_set_playback_rate(int sampleRateInHz); 984 private native final int native_get_playback_rate(); 985 986 private native final int native_set_marker_pos(int marker); 987 private native final int native_get_marker_pos(); 988 989 private native final int native_set_pos_update_period(int updatePeriod); 990 private native final int native_get_pos_update_period(); 991 992 private native final int native_set_position(int position); 993 private native final int native_get_position(); 994 995 private native final int native_set_loop(int start, int end, int loopCount); 996 997 static private native final int native_get_output_sample_rate(); 998 static private native final int native_get_min_buff_size( 999 int sampleRateInHz, int channelConfig, int audioFormat); 1000 1001 1002 //--------------------------------------------------------- 1003 // Utility methods 1004 //------------------ 1005 1006 private static void logd(String msg) { 1007 Log.d(TAG, "[ android.media.AudioTrack ] " + msg); 1008 } 1009 1010 private static void loge(String msg) { 1011 Log.e(TAG, "[ android.media.AudioTrack ] " + msg); 1012 } 1013 1014} 1015