AudioTrack.java revision d01721d5ca5bfa943760ed61cc99ca1ffc044c50
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 when the playback position reaches a marker 157 * or for periodic updates during the progression of the playback head. 158 * @see #setPlaybackPositionUpdateListener(OnPlaybackPositionUpdateListener) 159 */ 160 private OnPlaybackPositionUpdateListener mPositionListener = null; 161 /** 162 * Lock to protect event listener updates against event notifications 163 */ 164 private final Object mPositionListenerLock = new Object(); 165 /** 166 * Size of the native audio buffer. 167 */ 168 private int mNativeBufferSizeInBytes = 0; 169 /** 170 * Handler for marker events coming from the native code 171 */ 172 private NativeEventHandlerDelegate mEventHandlerDelegate = null; 173 /** 174 * Looper associated with the thread that creates the AudioTrack instance 175 */ 176 private Looper mInitializationLooper = null; 177 /** 178 * The audio data sampling rate in Hz. 179 */ 180 private int mSampleRate = 22050; 181 /** 182 * The number of input audio channels (1 is mono, 2 is stereo) 183 */ 184 private int mChannelCount = 1; 185 /** 186 * The type of the audio stream to play. See 187 * {@link AudioManager#STREAM_VOICE_CALL}, {@link AudioManager#STREAM_SYSTEM}, 188 * {@link AudioManager#STREAM_RING}, {@link AudioManager#STREAM_MUSIC} and 189 * {@link AudioManager#STREAM_ALARM} 190 */ 191 private int mStreamType = AudioManager.STREAM_MUSIC; 192 /** 193 * The way audio is consumed by the hardware, streaming or static. 194 */ 195 private int mDataLoadMode = MODE_STREAM; 196 /** 197 * The current audio channel configuration 198 */ 199 private int mChannelConfiguration = AudioFormat.CHANNEL_CONFIGURATION_MONO; 200 /** 201 * The encoding of the audio samples. 202 * @see AudioFormat#ENCODING_PCM_8BIT 203 * @see AudioFormat#ENCODING_PCM_16BIT 204 */ 205 private int mAudioFormat = AudioFormat.ENCODING_PCM_16BIT; 206 207 208 //-------------------------------- 209 // Used exclusively by native code 210 //-------------------- 211 /** 212 * Accessed by native methods: provides access to C++ AudioTrack object 213 */ 214 @SuppressWarnings("unused") 215 private int mNativeTrackInJavaObj; 216 /** 217 * Accessed by native methods: provides access to the JNI data (i.e. resources used by 218 * the native AudioTrack object, but not stored in it). 219 */ 220 @SuppressWarnings("unused") 221 private int mJniData; 222 223 224 //-------------------------------------------------------------------------- 225 // Constructor, Finalize 226 //-------------------- 227 /** 228 * Class constructor. 229 * @param streamType the type of the audio stream. See 230 231 * {@link AudioManager#STREAM_VOICE_CALL}, {@link AudioManager#STREAM_SYSTEM}, 232 * {@link AudioManager#STREAM_RING}, {@link AudioManager#STREAM_MUSIC} and 233 * {@link AudioManager#STREAM_ALARM} 234 * @param sampleRateInHz the sample rate expressed in Hertz. Examples of rates are (but 235 * not limited to) 44100, 22050 and 11025. 236 * @param channelConfig describes the configuration of the audio channels. 237 238 * See {@link AudioFormat#CHANNEL_CONFIGURATION_MONO} and 239 * {@link AudioFormat#CHANNEL_CONFIGURATION_STEREO} 240 241 * @param audioFormat the format in which the audio data is represented. 242 * See {@link AudioFormat#ENCODING_PCM_16BIT} and 243 * {@link AudioFormat#ENCODING_PCM_8BIT} 244 * @param bufferSizeInBytes the total size (in bytes) of the buffer where audio data is read 245 * from for playback. If using the AudioTrack in streaming mode, you can write data into 246 * this buffer in smaller chunks than this size. If using the AudioTrack in static mode, 247 * this is the maximum size of the sound that will be played for this instance. 248 * @param mode streaming or static buffer. See {@link #MODE_STATIC} and {@link #MODE_STREAM} 249 * @throws java.lang.IllegalArgumentException 250 */ 251 public AudioTrack(int streamType, int sampleRateInHz, int channelConfig, int audioFormat, 252 int bufferSizeInBytes, int mode) 253 throws IllegalArgumentException { 254 mState = STATE_UNINITIALIZED; 255 256 // remember which looper is associated with the AudioTrack instanciation 257 if ((mInitializationLooper = Looper.myLooper()) == null) { 258 mInitializationLooper = Looper.getMainLooper(); 259 } 260 261 audioParamCheck(streamType, sampleRateInHz, channelConfig, audioFormat, mode); 262 263 audioBuffSizeCheck(bufferSizeInBytes); 264 265 // native initialization 266 int initResult = native_setup(new WeakReference<AudioTrack>(this), 267 mStreamType, mSampleRate, mChannelCount, mAudioFormat, 268 mNativeBufferSizeInBytes, mDataLoadMode); 269 if (initResult != SUCCESS) { 270 loge("Error code "+initResult+" when initializing AudioTrack."); 271 return; // with mState == STATE_UNINITIALIZED 272 } 273 274 if (mDataLoadMode == MODE_STATIC) { 275 mState = STATE_NO_STATIC_DATA; 276 } else { 277 mState = STATE_INITIALIZED; 278 } 279 } 280 281 282 // Convenience method for the constructor's parameter checks. 283 // This is where constructor IllegalArgumentException-s are thrown 284 // postconditions: 285 // mStreamType is valid 286 // mChannelCount is valid 287 // mAudioFormat is valid 288 // mSampleRate is valid 289 // mDataLoadMode is valid 290 private void audioParamCheck(int streamType, int sampleRateInHz, 291 int channelConfig, int audioFormat, int mode) { 292 293 //-------------- 294 // stream type 295 if( (streamType != AudioManager.STREAM_ALARM) && (streamType != AudioManager.STREAM_MUSIC) 296 && (streamType != AudioManager.STREAM_RING) && (streamType != AudioManager.STREAM_SYSTEM) 297 && (streamType != AudioManager.STREAM_VOICE_CALL) 298 && (streamType != AudioManager.STREAM_NOTIFICATION) 299 && (streamType != AudioManager.STREAM_BLUETOOTH_SCO)) { 300 throw (new IllegalArgumentException("Invalid stream type.")); 301 } else { 302 mStreamType = streamType; 303 } 304 305 //-------------- 306 // sample rate 307 if ( (sampleRateInHz < 4000) || (sampleRateInHz > 48000) ) { 308 throw (new IllegalArgumentException(sampleRateInHz 309 + "Hz is not a supported sample rate.")); 310 } else { 311 mSampleRate = sampleRateInHz; 312 } 313 314 //-------------- 315 // channel config 316 switch (channelConfig) { 317 case AudioFormat.CHANNEL_CONFIGURATION_DEFAULT: 318 case AudioFormat.CHANNEL_CONFIGURATION_MONO: 319 mChannelCount = 1; 320 mChannelConfiguration = AudioFormat.CHANNEL_CONFIGURATION_MONO; 321 break; 322 case AudioFormat.CHANNEL_CONFIGURATION_STEREO: 323 mChannelCount = 2; 324 mChannelConfiguration = AudioFormat.CHANNEL_CONFIGURATION_STEREO; 325 break; 326 default: 327 mChannelCount = 0; 328 mChannelConfiguration = AudioFormat.CHANNEL_CONFIGURATION_INVALID; 329 throw(new IllegalArgumentException("Unsupported channel configuration.")); 330 } 331 332 //-------------- 333 // audio format 334 switch (audioFormat) { 335 case AudioFormat.ENCODING_DEFAULT: 336 mAudioFormat = AudioFormat.ENCODING_PCM_16BIT; 337 break; 338 case AudioFormat.ENCODING_PCM_16BIT: 339 case AudioFormat.ENCODING_PCM_8BIT: 340 mAudioFormat = audioFormat; 341 break; 342 default: 343 mAudioFormat = AudioFormat.ENCODING_INVALID; 344 throw(new IllegalArgumentException("Unsupported sample encoding." 345 + " Should be ENCODING_PCM_8BIT or ENCODING_PCM_16BIT.")); 346 } 347 348 //-------------- 349 // audio load mode 350 if ( (mode != MODE_STREAM) && (mode != MODE_STATIC) ) { 351 throw(new IllegalArgumentException("Invalid mode.")); 352 } else { 353 mDataLoadMode = mode; 354 } 355 } 356 357 358 // Convenience method for the contructor's audio buffer size check. 359 // preconditions: 360 // mChannelCount is valid 361 // mAudioFormat is valid 362 // postcondition: 363 // mNativeBufferSizeInBytes is valid (multiple of frame size, positive) 364 private void audioBuffSizeCheck(int audioBufferSize) { 365 // NB: this section is only valid with PCM data. 366 // To update when supporting compressed formats 367 int frameSizeInBytes = mChannelCount 368 * (mAudioFormat == AudioFormat.ENCODING_PCM_8BIT ? 1 : 2); 369 if ((audioBufferSize % frameSizeInBytes != 0) || (audioBufferSize < 1)) { 370 throw (new IllegalArgumentException("Invalid audio buffer size.")); 371 } 372 373 mNativeBufferSizeInBytes = audioBufferSize; 374 } 375 376 377 /** 378 * Releases the native AudioTrack resources. 379 */ 380 public void release() { 381 // even though native_release() stops the native AudioTrack, we need to stop 382 // AudioTrack subclasses too. 383 try { 384 stop(); 385 } catch(IllegalStateException ise) { 386 // don't raise an exception, we're releasing the resources. 387 } 388 native_release(); 389 mState = STATE_UNINITIALIZED; 390 } 391 392 @Override 393 protected void finalize() { 394 native_finalize(); 395 } 396 397 //-------------------------------------------------------------------------- 398 // Getters 399 //-------------------- 400 /** 401 * Returns the minimum valid volume value. Volume values set under this one will 402 * be clamped at this value. 403 * @return the minimum volume expressed as a linear attenuation. 404 */ 405 static public float getMinVolume() { 406 return AudioTrack.VOLUME_MIN; 407 } 408 409 /** 410 * Returns the maximum valid volume value. Volume values set above this one will 411 * be clamped at this value. 412 * @return the maximum volume expressed as a linear attenuation. 413 */ 414 static public float getMaxVolume() { 415 return AudioTrack.VOLUME_MAX; 416 } 417 418 /** 419 * Returns the configured audio data sample rate in Hz 420 */ 421 public int getSampleRate() { 422 return mSampleRate; 423 } 424 425 /** 426 * Returns the current playback rate in Hz. Note that this rate may differ from one set using 427 * {@link #setPlaybackRate(int)} as the value effectively set is implementation-dependent. 428 */ 429 public int getPlaybackRate() { 430 return native_get_playback_rate(); 431 } 432 433 /** 434 * Returns the configured audio data format. See {@link AudioFormat#ENCODING_PCM_16BIT} 435 * and {@link AudioFormat#ENCODING_PCM_8BIT}. 436 */ 437 public int getAudioFormat() { 438 return mAudioFormat; 439 } 440 441 /** 442 * Returns the type of audio stream this AudioTrack is configured for. 443 * Compare the result against {@link AudioManager#STREAM_VOICE_CALL}, 444 * {@link AudioManager#STREAM_SYSTEM}, {@link AudioManager#STREAM_RING}, 445 * {@link AudioManager#STREAM_MUSIC} or {@link AudioManager#STREAM_ALARM} 446 */ 447 public int getStreamType() { 448 return mStreamType; 449 } 450 451 /** 452 * Returns the configured channel configuration. 453 454 * See {@link AudioFormat#CHANNEL_CONFIGURATION_MONO} 455 * and {@link AudioFormat#CHANNEL_CONFIGURATION_STEREO}. 456 */ 457 public int getChannelConfiguration() { 458 return mChannelConfiguration; 459 } 460 461 /** 462 * Returns the configured number of channels. 463 */ 464 public int getChannelCount() { 465 return mChannelCount; 466 } 467 468 /** 469 * Returns the state of the AudioTrack instance. This is useful after the 470 * AudioTrack instance has been created to check if it was initialized 471 * properly. This ensures that the appropriate hardware resources have been 472 * acquired. 473 */ 474 public int getState() { 475 return mState; 476 } 477 478 /** 479 * Returns the playback state of the AudioTrack instance. 480 * @see #PLAYSTATE_STOPPED 481 * @see #PLAYSTATE_PAUSED 482 * @see #PLAYSTATE_PLAYING 483 */ 484 public int getPlayState() { 485 return mPlayState; 486 } 487 488 /** 489 * Returns the native frame count used by the hardware 490 */ 491 protected int getNativeFrameCount() { 492 return native_get_native_frame_count(); 493 } 494 495 /** 496 * @return marker position in frames 497 */ 498 public int getNotificationMarkerPosition() { 499 return native_get_marker_pos(); 500 } 501 502 /** 503 * @return update period in frames 504 */ 505 public int getPositionNotificationPeriod() { 506 return native_get_pos_update_period(); 507 } 508 509 /** 510 * @return playback head position in frames 511 */ 512 public int getPlaybackHeadPosition() { 513 return native_get_position(); 514 } 515 516 /** 517 * Returns the hardware output sample rate 518 */ 519 static public int getNativeOutputSampleRate(int streamType) { 520 return native_get_output_sample_rate(streamType); 521 } 522 523 /** 524 * Returns the minimum buffer size required for the successful creation of an AudioTrack 525 * object to be created in the {@link #MODE_STREAM} mode. 526 * @param sampleRateInHz the sample rate expressed in Hertz. 527 * @param channelConfig describes the configuration of the audio channels. 528 * See {@link AudioFormat#CHANNEL_CONFIGURATION_MONO} and 529 * {@link AudioFormat#CHANNEL_CONFIGURATION_STEREO} 530 * @param audioFormat the format in which the audio data is represented. 531 * See {@link AudioFormat#ENCODING_PCM_16BIT} and 532 * {@link AudioFormat#ENCODING_PCM_8BIT} 533 * @return {@link #ERROR_BAD_VALUE} if an invalid parameter was passed, 534 * or {@link #ERROR} if the implementation was unable to query the hardware for its output 535 * properties, 536 * or the minimum buffer size expressed in number of bytes. 537 */ 538 static public int getMinBufferSize(int sampleRateInHz, int channelConfig, int audioFormat) { 539 int channelCount = 0; 540 switch(channelConfig) { 541 case AudioFormat.CHANNEL_CONFIGURATION_MONO: 542 channelCount = 1; 543 break; 544 case AudioFormat.CHANNEL_CONFIGURATION_STEREO: 545 channelCount = 2; 546 break; 547 default: 548 loge("getMinBufferSize(): Invalid channel configuration."); 549 return AudioTrack.ERROR_BAD_VALUE; 550 } 551 552 if ((audioFormat != AudioFormat.ENCODING_PCM_16BIT) 553 && (audioFormat != AudioFormat.ENCODING_PCM_8BIT)) { 554 loge("getMinBufferSize(): Invalid audio format."); 555 return AudioTrack.ERROR_BAD_VALUE; 556 } 557 558 if ( (sampleRateInHz < 4000) || (sampleRateInHz > 48000) ) { 559 loge("getMinBufferSize(): " + sampleRateInHz +"Hz is not a supported sample rate."); 560 return AudioTrack.ERROR_BAD_VALUE; 561 } 562 563 int size = native_get_min_buff_size(sampleRateInHz, channelCount, audioFormat); 564 if ((size == -1) || (size == 0)) { 565 loge("getMinBufferSize(): error querying hardware"); 566 return AudioTrack.ERROR; 567 } 568 else { 569 return size; 570 } 571 } 572 573 574 //-------------------------------------------------------------------------- 575 // Initialization / configuration 576 //-------------------- 577 /** 578 * Sets the listener the AudioTrack notifies when a previously set marker is reached or 579 * for each periodic playback head position update. 580 * @param listener 581 */ 582 public void setPlaybackPositionUpdateListener(OnPlaybackPositionUpdateListener listener) { 583 setPlaybackPositionUpdateListener(listener, null); 584 } 585 586 587 public void setPlaybackPositionUpdateListener(OnPlaybackPositionUpdateListener listener, 588 Handler handler) { 589 synchronized (mPositionListenerLock) { 590 mPositionListener = listener; 591 } 592 if (listener != null) { 593 mEventHandlerDelegate = new NativeEventHandlerDelegate(this, handler); 594 } 595 596 } 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(int)}). 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}, {@link #ERROR_BAD_VALUE}, 644 * {@link #ERROR_INVALID_OPERATION} 645 */ 646 public int setPlaybackRate(int sampleRateInHz) { 647 if (mState != STATE_INITIALIZED) { 648 return ERROR_INVALID_OPERATION; 649 } 650 if (sampleRateInHz <= 0) { 651 return ERROR_BAD_VALUE; 652 } 653 native_set_playback_rate(sampleRateInHz); 654 return SUCCESS; 655 } 656 657 658 /** 659 * 660 * @param markerInFrames marker in frames 661 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 662 * {@link #ERROR_INVALID_OPERATION} 663 */ 664 public int setNotificationMarkerPosition(int markerInFrames) { 665 if (mState != STATE_INITIALIZED) { 666 return ERROR_INVALID_OPERATION; 667 } 668 return native_set_marker_pos(markerInFrames); 669 } 670 671 672 /** 673 * @param periodInFrames update period in frames 674 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_INVALID_OPERATION} 675 */ 676 public int setPositionNotificationPeriod(int periodInFrames) { 677 if (mState != STATE_INITIALIZED) { 678 return ERROR_INVALID_OPERATION; 679 } 680 return native_set_pos_update_period(periodInFrames); 681 } 682 683 684 /** 685 * Sets the playback head position. The track must be stopped for the position to be changed. 686 * @param positionInFrames playback head position in frames 687 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 688 * {@link #ERROR_INVALID_OPERATION} 689 */ 690 public int setPlaybackHeadPosition(int positionInFrames) { 691 synchronized(mPlayStateLock) { 692 if ((mPlayState == PLAYSTATE_STOPPED) || (mPlayState == PLAYSTATE_PAUSED)) { 693 return native_set_position(positionInFrames); 694 } else { 695 return ERROR_INVALID_OPERATION; 696 } 697 } 698 } 699 700 /** 701 * Sets the loop points and the loop count. The loop can be infinite. 702 * @param startInFrames loop start marker in frames 703 * @param endInFrames loop end marker in frames 704 * @param loopCount the number of times the loop is looped. 705 * A value of -1 means infinite looping. 706 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 707 * {@link #ERROR_INVALID_OPERATION} 708 */ 709 public int setLoopPoints(int startInFrames, int endInFrames, int loopCount) { 710 if (mDataLoadMode == MODE_STREAM) { 711 return ERROR_INVALID_OPERATION; 712 } 713 return native_set_loop(startInFrames, endInFrames, loopCount); 714 } 715 716 /** 717 * Sets the initialization state of the instance. To be used in an AudioTrack subclass 718 * constructor to set a subclass-specific post-initialization state. 719 * @param state the state of the AudioTrack instance 720 */ 721 protected void setState(int state) { 722 mState = state; 723 } 724 725 726 //--------------------------------------------------------- 727 // Transport control methods 728 //-------------------- 729 /** 730 * Starts playing an AudioTrack. 731 * @throws IllegalStateException 732 */ 733 public void play() 734 throws IllegalStateException { 735 if (mState != STATE_INITIALIZED) { 736 throw(new IllegalStateException("play() called on uninitialized AudioTrack.")); 737 } 738 739 synchronized(mPlayStateLock) { 740 native_start(); 741 mPlayState = PLAYSTATE_PLAYING; 742 } 743 } 744 745 /** 746 * Stops playing the audio data. 747 * @throws IllegalStateException 748 */ 749 public void stop() 750 throws IllegalStateException { 751 if (mState != STATE_INITIALIZED) { 752 throw(new IllegalStateException("stop() called on uninitialized AudioTrack.")); 753 } 754 755 // stop playing 756 synchronized(mPlayStateLock) { 757 native_stop(); 758 mPlayState = PLAYSTATE_STOPPED; 759 } 760 } 761 762 /** 763 * Pauses the playback of the audio data. 764 * @throws IllegalStateException 765 */ 766 public void pause() 767 throws IllegalStateException { 768 if (mState != STATE_INITIALIZED) { 769 throw(new IllegalStateException("pause() called on uninitialized AudioTrack.")); 770 } 771 //logd("pause()"); 772 773 // pause playback 774 synchronized(mPlayStateLock) { 775 native_pause(); 776 mPlayState = PLAYSTATE_PAUSED; 777 } 778 } 779 780 781 //--------------------------------------------------------- 782 // Audio data supply 783 //-------------------- 784 785 /** 786 * Flushes the audio data currently queued for playback. 787 */ 788 789 public void flush() { 790 if (mState == STATE_INITIALIZED) { 791 // flush the data in native layer 792 native_flush(); 793 } 794 795 } 796 797 /** 798 * Writes the audio data to the audio hardware for playback. 799 * @param audioData the array that holds the data to play. 800 * @param offsetInBytes the offset in audioData where the data to play starts. 801 * @param sizeInBytes the number of bytes to read in audioData after the offset. 802 * @return the number of bytes that were written or {@link #ERROR_INVALID_OPERATION} 803 * if the object wasn't properly initialized, or {@link #ERROR_BAD_VALUE} if 804 * the parameters don't resolve to valid data and indexes. 805 */ 806 807 public int write(byte[] audioData,int offsetInBytes, int sizeInBytes) { 808 if ((mDataLoadMode == MODE_STATIC) 809 && (mState == STATE_NO_STATIC_DATA) 810 && (sizeInBytes > 0)) { 811 mState = STATE_INITIALIZED; 812 } 813 814 if (mState != STATE_INITIALIZED) { 815 return ERROR_INVALID_OPERATION; 816 } 817 818 if ( (audioData == null) || (offsetInBytes < 0 ) || (sizeInBytes < 0) 819 || (offsetInBytes + sizeInBytes > audioData.length)) { 820 return ERROR_BAD_VALUE; 821 } 822 823 return native_write_byte(audioData, offsetInBytes, sizeInBytes, mAudioFormat); 824 } 825 826 827 /** 828 * Writes the audio data to the audio hardware for playback. 829 * @param audioData the array that holds the data to play. 830 * @param offsetInShorts the offset in audioData where the data to play starts. 831 * @param sizeInShorts the number of bytes to read in audioData after the offset. 832 * @return the number of shorts that were written or {@link #ERROR_INVALID_OPERATION} 833 * if the object wasn't properly initialized, or {@link #ERROR_BAD_VALUE} if 834 * the parameters don't resolve to valid data and indexes. 835 */ 836 837 public int write(short[] audioData, int offsetInShorts, int sizeInShorts) { 838 if ((mDataLoadMode == MODE_STATIC) 839 && (mState == STATE_NO_STATIC_DATA) 840 && (sizeInShorts > 0)) { 841 mState = STATE_INITIALIZED; 842 } 843 844 if (mState != STATE_INITIALIZED) { 845 return ERROR_INVALID_OPERATION; 846 } 847 848 if ( (audioData == null) || (offsetInShorts < 0 ) || (sizeInShorts < 0) 849 || (offsetInShorts + sizeInShorts > audioData.length)) { 850 return ERROR_BAD_VALUE; 851 } 852 853 return native_write_short(audioData, offsetInShorts, sizeInShorts, mAudioFormat); 854 } 855 856 857 /** 858 * Notifies the native resource to reuse the audio data already loaded in the native 859 * layer. This call is only valid with AudioTrack instances that don't use the streaming 860 * model. 861 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 862 * {@link #ERROR_INVALID_OPERATION} 863 */ 864 public int reloadStaticData() { 865 if (mDataLoadMode == MODE_STREAM) { 866 return ERROR_INVALID_OPERATION; 867 } 868 return native_reload_static(); 869 } 870 871 872 //--------------------------------------------------------- 873 // Interface definitions 874 //-------------------- 875 /** 876 * Interface definition for a callback to be invoked when the playback head position of 877 * an AudioTrack has reached a notification marker or has increased by a certain period. 878 */ 879 public interface OnPlaybackPositionUpdateListener { 880 /** 881 * Called on the listener to notify it that the previously set marker has been reached 882 * by the playback head. 883 */ 884 void onMarkerReached(AudioTrack track); 885 886 /** 887 * Called on the listener to periodically notify it that the playback head has reached 888 * a multiple of the notification period. 889 */ 890 void onPeriodicNotification(AudioTrack track); 891 } 892 893 894 //--------------------------------------------------------- 895 // Inner classes 896 //-------------------- 897 /** 898 * Helper class to handle the forwarding of native events to the appropriate listener 899 * (potentially) handled in a different thread 900 */ 901 private class NativeEventHandlerDelegate { 902 private final AudioTrack mAudioTrack; 903 private final Handler mHandler; 904 905 NativeEventHandlerDelegate(AudioTrack track, Handler handler) { 906 mAudioTrack = track; 907 // find the looper for our new event handler 908 Looper looper; 909 if (handler != null) { 910 looper = handler.getLooper(); 911 } else { 912 // no given handler, use the looper the AudioTrack was created in 913 looper = mInitializationLooper; 914 } 915 916 // construct the event handler with this looper 917 if (looper != null) { 918 // implement the event handler delegate 919 mHandler = new Handler(looper) { 920 @Override 921 public void handleMessage(Message msg) { 922 if (mAudioTrack == null) { 923 return; 924 } 925 OnPlaybackPositionUpdateListener listener = null; 926 synchronized (mPositionListenerLock) { 927 listener = mAudioTrack.mPositionListener; 928 } 929 switch(msg.what) { 930 case NATIVE_EVENT_MARKER: 931 if (listener != null) { 932 listener.onMarkerReached(mAudioTrack); 933 } 934 break; 935 case NATIVE_EVENT_NEW_POS: 936 if (listener != null) { 937 listener.onPeriodicNotification(mAudioTrack); 938 } 939 break; 940 default: 941 Log.e(TAG, "[ android.media.AudioTrack.NativeEventHandler ] " + 942 "Unknown event type: " + msg.what); 943 break; 944 } 945 } 946 }; 947 } else { 948 mHandler = null; 949 } 950 } 951 952 Handler getHandler() { 953 return mHandler; 954 } 955 } 956 957 958 //--------------------------------------------------------- 959 // Java methods called from the native side 960 //-------------------- 961 @SuppressWarnings("unused") 962 private static void postEventFromNative(Object audiotrack_ref, 963 int what, int arg1, int arg2, Object obj) { 964 //logd("Event posted from the native side: event="+ what + " args="+ arg1+" "+arg2); 965 AudioTrack track = (AudioTrack)((WeakReference)audiotrack_ref).get(); 966 if (track == null) { 967 return; 968 } 969 970 if (track.mEventHandlerDelegate != null) { 971 Message m = 972 track.mEventHandlerDelegate.getHandler().obtainMessage(what, arg1, arg2, obj); 973 track.mEventHandlerDelegate.getHandler().sendMessage(m); 974 } 975 976 } 977 978 979 //--------------------------------------------------------- 980 // Native methods called from the Java side 981 //-------------------- 982 983 private native final int native_setup(Object audiotrack_this, 984 int streamType, int sampleRate, int nbChannels, int audioFormat, 985 int buffSizeInBytes, int mode); 986 987 private native final void native_finalize(); 988 989 private native final void native_release(); 990 991 private native final void native_start(); 992 993 private native final void native_stop(); 994 995 private native final void native_pause(); 996 997 private native final void native_flush(); 998 999 private native final int native_write_byte(byte[] audioData, 1000 int offsetInBytes, int sizeInBytes, int format); 1001 1002 private native final int native_write_short(short[] audioData, 1003 int offsetInShorts, int sizeInShorts, int format); 1004 1005 private native final int native_reload_static(); 1006 1007 private native final int native_get_native_frame_count(); 1008 1009 private native final void native_setVolume(float leftVolume, float rightVolume); 1010 1011 private native final void native_set_playback_rate(int sampleRateInHz); 1012 private native final int native_get_playback_rate(); 1013 1014 private native final int native_set_marker_pos(int marker); 1015 private native final int native_get_marker_pos(); 1016 1017 private native final int native_set_pos_update_period(int updatePeriod); 1018 private native final int native_get_pos_update_period(); 1019 1020 private native final int native_set_position(int position); 1021 private native final int native_get_position(); 1022 1023 private native final int native_set_loop(int start, int end, int loopCount); 1024 1025 static private native final int native_get_output_sample_rate(int streamType); 1026 static private native final int native_get_min_buff_size( 1027 int sampleRateInHz, int channelConfig, int audioFormat); 1028 1029 1030 //--------------------------------------------------------- 1031 // Utility methods 1032 //------------------ 1033 1034 private static void logd(String msg) { 1035 Log.d(TAG, "[ android.media.AudioTrack ] " + msg); 1036 } 1037 1038 private static void loge(String msg) { 1039 Log.e(TAG, "[ android.media.AudioTrack ] " + msg); 1040 } 1041 1042} 1043