AudioTrack.java revision 076357b8567458d4b6dfdcf839ef751634cd2bfb
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 {@link #ERROR_BAD_VALUE} if an invalid parameter was passed, 542 * or {@link #ERROR} if the implementation was unable to query the hardware for its output 543 * properties, 544 * or the minimum buffer size expressed in number of bytes. 545 */ 546 static public int getMinBufferSize(int sampleRateInHz, int channelConfig, int audioFormat) { 547 int channelCount = 0; 548 switch(channelConfig) { 549 case AudioFormat.CHANNEL_CONFIGURATION_MONO: 550 channelCount = 1; 551 break; 552 case AudioFormat.CHANNEL_CONFIGURATION_STEREO: 553 channelCount = 2; 554 break; 555 default: 556 loge("getMinBufferSize(): Invalid channel configuration."); 557 return AudioTrack.ERROR_BAD_VALUE; 558 } 559 560 if ((audioFormat != AudioFormat.ENCODING_PCM_16BIT) 561 && (audioFormat != AudioFormat.ENCODING_PCM_8BIT)) { 562 loge("getMinBufferSize(): Invalid audio format."); 563 return AudioTrack.ERROR_BAD_VALUE; 564 } 565 566 if ( (sampleRateInHz < 4000) || (sampleRateInHz > 48000) ) { 567 loge("getMinBufferSize(): " + sampleRateInHz +"Hz is not a supported sample rate."); 568 return AudioTrack.ERROR_BAD_VALUE; 569 } 570 571 int size = native_get_min_buff_size(sampleRateInHz, channelCount, audioFormat); 572 if ((size == -1) || (size == 0)) { 573 loge("getMinBufferSize(): error querying hardware"); 574 return AudioTrack.ERROR; 575 } 576 else { 577 return size; 578 } 579 } 580 581 582 //-------------------------------------------------------------------------- 583 // Initialization / configuration 584 //-------------------- 585 /** 586 * Sets the listener the AudioTrack notifies when a previously set marker is reached. 587 * @param listener 588 */ 589 public void setMarkerReachedListener(OnMarkerReachedListener listener) { 590 synchronized (mMarkerListenerLock) { 591 mMarkerListener = listener; 592 } 593 if ((listener != null) && (mNativeEventHandler == null)) { 594 createNativeEventHandler(); 595 } 596 } 597 598 599 /** 600 * Sets the listener the AudioTrack notifies periodically during playback. 601 * @param listener 602 */ 603 public void setPeriodicNotificationListener(OnPeriodicNotificationListener listener) { 604 synchronized (mPeriodicListenerLock) { 605 mPeriodicListener = listener; 606 } 607 if ((listener != null) && (mNativeEventHandler == null)) { 608 createNativeEventHandler(); 609 } 610 } 611 612 613 /** 614 * Sets the specified left/right output volume values on the AudioTrack. Values are clamped 615 * to the ({@link #getMinVolume()}, {@link #getMaxVolume()}) interval if outside this range. 616 * @param leftVolume output attenuation for the left channel. A value of 0.0f is silence, 617 * a value of 1.0f is no attenuation. 618 * @param rightVolume output attenuation for the right channel 619 * @return error code or success, see {@link #SUCCESS}, 620 * {@link #ERROR_INVALID_OPERATION} 621 */ 622 public int setStereoVolume(float leftVolume, float rightVolume) { 623 if (mState != STATE_INITIALIZED) { 624 return ERROR_INVALID_OPERATION; 625 } 626 627 // clamp the volumes 628 if (leftVolume < getMinVolume()) { 629 leftVolume = getMinVolume(); 630 } 631 if (leftVolume > getMaxVolume()) { 632 leftVolume = getMaxVolume(); 633 } 634 if (rightVolume < getMinVolume()) { 635 rightVolume = getMinVolume(); 636 } 637 if (rightVolume > getMaxVolume()) { 638 rightVolume = getMaxVolume(); 639 } 640 641 native_setVolume(leftVolume, rightVolume); 642 643 return SUCCESS; 644 } 645 646 647 /** 648 * Sets the playback sample rate for this track. This sets the sampling rate at which 649 * the audio data will be consumed and played back, not the original sampling rate of the 650 * content. Setting it to half the sample rate of the content will cause the playback to 651 * last twice as long, but will also result result in a negative pitch shift. 652 * The current implementation supports a maximum sample rate of twice the hardware output 653 * sample rate (see {@link #getNativeOutputSampleRate()}). Use {@link #getSampleRate()} to 654 * check the rate actually used in hardware after potential clamping. 655 * @param sampleRateInHz 656 * @return error code or success, see {@link #SUCCESS}, 657 * {@link #ERROR_INVALID_OPERATION} 658 */ 659 public int setPlaybackRate(int sampleRateInHz) { 660 if (mState != STATE_INITIALIZED) { 661 return ERROR_INVALID_OPERATION; 662 } 663 native_set_playback_rate(sampleRateInHz); 664 return SUCCESS; 665 } 666 667 668 /** 669 * 670 * @param markerInFrames marker in frames 671 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 672 * {@link #ERROR_INVALID_OPERATION} 673 */ 674 public int setNotificationMarkerPosition(int markerInFrames) { 675 if (mState != STATE_INITIALIZED) { 676 return ERROR_INVALID_OPERATION; 677 } 678 return native_set_marker_pos(markerInFrames); 679 } 680 681 682 /** 683 * @param periodInFrames update period in frames 684 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_INVALID_OPERATION} 685 */ 686 public int setPositionNotificationPeriod(int periodInFrames) { 687 if (mState != STATE_INITIALIZED) { 688 return ERROR_INVALID_OPERATION; 689 } 690 return native_set_pos_update_period(periodInFrames); 691 } 692 693 694 /** 695 * Sets the playback head position. The track must be stopped for the position to be changed. 696 * @param positionInFrames playback head position in frames 697 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 698 * {@link #ERROR_INVALID_OPERATION} 699 */ 700 public int setPlaybackHeadPosition(int positionInFrames) { 701 synchronized(mPlayStateLock) { 702 if(mPlayState == PLAYSTATE_STOPPED) { 703 return native_set_position(positionInFrames); 704 } else { 705 return ERROR_INVALID_OPERATION; 706 } 707 } 708 } 709 710 /** 711 * Sets the loop points and the loop count. The loop can be infinite. 712 * @param startInFrames loop start marker in frames 713 * @param endInFrames loop end marker in frames 714 * @param loopCount the number of times the loop is looped. 715 * A value of -1 means infinite looping. 716 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 717 * {@link #ERROR_INVALID_OPERATION} 718 */ 719 public int setLoopPoints(int startInFrames, int endInFrames, int loopCount) { 720 return native_set_loop(startInFrames, endInFrames, loopCount); 721 } 722 723 /** 724 * Sets the initialization state of the instance. To be used in an AudioTrack subclass 725 * constructor to set a subclass-specific post-initialization state. 726 * @param state the state of the AudioTrack instance 727 */ 728 protected void setState(int state) { 729 mState = state; 730 } 731 732 733 //--------------------------------------------------------- 734 // Transport control methods 735 //-------------------- 736 /** 737 * Starts playing an AudioTrack. 738 * @throws IllegalStateException 739 */ 740 public void play() 741 throws IllegalStateException { 742 if (mState != STATE_INITIALIZED) { 743 throw(new IllegalStateException("play() called on uninitialized AudioTrack.")); 744 } 745 746 synchronized(mPlayStateLock) { 747 native_start(); 748 mPlayState = PLAYSTATE_PLAYING; 749 } 750 } 751 752 /** 753 * Stops playing the audio data. 754 * @throws IllegalStateException 755 */ 756 public void stop() 757 throws IllegalStateException { 758 if (mState != STATE_INITIALIZED) { 759 throw(new IllegalStateException("stop() called on uninitialized AudioTrack.")); 760 } 761 762 // stop playing 763 synchronized(mPlayStateLock) { 764 native_stop(); 765 mPlayState = PLAYSTATE_STOPPED; 766 } 767 } 768 769 /** 770 * Pauses the playback of the audio data. 771 * @throws IllegalStateException 772 */ 773 public void pause() 774 throws IllegalStateException { 775 if (mState != STATE_INITIALIZED) { 776 throw(new IllegalStateException("pause() called on uninitialized AudioTrack.")); 777 } 778 //logd("pause()"); 779 780 // pause playback 781 synchronized(mPlayStateLock) { 782 native_pause(); 783 mPlayState = PLAYSTATE_PAUSED; 784 } 785 } 786 787 788 //--------------------------------------------------------- 789 // Audio data supply 790 //-------------------- 791 792 /** 793 * Flushes the audio data currently queued for playback. 794 */ 795 796 public void flush() { 797 if (mState == STATE_INITIALIZED) { 798 // flush the data in native layer 799 native_flush(); 800 } 801 802 } 803 804 /** 805 * Writes the audio data to the audio hardware for playback. 806 * @param audioData the array that holds the data to play. 807 * @param offsetInBytes the offset in audioData where the data to play starts. 808 * @param sizeInBytes the number of bytes to read in audioData after the offset. 809 * @return the number of bytes that were written or -1 if the object wasn't properly 810 * initialized. 811 */ 812 813 public int write(byte[] audioData,int offsetInBytes, int sizeInBytes) { 814 if ((mDataLoadMode == MODE_STATIC) 815 && (mState == STATE_NO_STATIC_DATA) 816 && (sizeInBytes > 0)) { 817 mState = STATE_INITIALIZED; 818 } 819 //TODO check if future writes should be forbidden for static tracks 820 // or: how to update data for static tracks? 821 822 if (mState != STATE_INITIALIZED) { 823 return -1; 824 } 825 826 return native_write_byte(audioData, offsetInBytes, sizeInBytes, mAudioFormat); 827 } 828 829 830 /** 831 * Writes the audio data to the audio hardware for playback. 832 * @param audioData the array that holds the data to play. 833 * @param offsetInShorts the offset in audioData where the data to play starts. 834 * @param sizeInShorts the number of bytes to read in audioData after the offset. 835 * @return the number of shorts that were written or -1 if the object wasn't properly 836 * initialized. 837 */ 838 839 public int write(short[] audioData, int offsetInShorts, int sizeInShorts) { 840 if ((mDataLoadMode == MODE_STATIC) 841 && (mState == STATE_NO_STATIC_DATA) 842 && (sizeInShorts > 0)) { 843 mState = STATE_INITIALIZED; 844 } 845 //TODO check if future writes should be forbidden for static tracks 846 // or: how to update data for static tracks? 847 848 if (mState != STATE_INITIALIZED) { 849 return -1; 850 } 851 852 return native_write_short(audioData, offsetInShorts, sizeInShorts, mAudioFormat); 853 } 854 855 856 /** 857 * Notifies the native resource to reuse the audio data already loaded in the native 858 * layer. This call is only valid with AudioTrack instances that don't use the streaming 859 * model. 860 * @return error code or success, see {@link #SUCCESS}, {@link #ERROR_BAD_VALUE}, 861 * {@link #ERROR_INVALID_OPERATION} 862 */ 863 public int reloadStaticData() { 864 if (mDataLoadMode == MODE_STREAM) { 865 return ERROR_INVALID_OPERATION; 866 } 867 return native_reload_static(); 868 } 869 870 871 //--------------------------------------------------------- 872 // Interface definitions 873 //-------------------- 874 /** 875 * Interface definition for a callback to be invoked when an AudioTrack has 876 * reached a notification marker set by setNotificationMarkerPosition(). 877 */ 878 public interface OnMarkerReachedListener { 879 /** 880 * Called on the listener to notify it that the previously set marker has been reached 881 * by the playback head. 882 */ 883 void onMarkerReached(AudioTrack track); 884 } 885 886 887 /** 888 * Interface definition for a callback to be invoked for each periodic AudioTrack 889 * update during playback. The update interval is set by setPositionNotificationPeriod(). 890 */ 891 public interface OnPeriodicNotificationListener { 892 /** 893 * Called on the listener to periodically notify it that the playback head has reached 894 * a multiple of the notification period. 895 */ 896 void onPeriodicNotification(AudioTrack track); 897 } 898 899 900 //--------------------------------------------------------- 901 // Inner classes 902 //-------------------- 903 /** 904 * Helper class to handle the forwarding of native events to the appropriate listeners 905 */ 906 private class NativeEventHandler extends Handler 907 { 908 private AudioTrack mAudioTrack; 909 910 public NativeEventHandler(AudioTrack mp, Looper looper) { 911 super(looper); 912 mAudioTrack = mp; 913 } 914 915 @Override 916 public void handleMessage(Message msg) { 917 if (mAudioTrack == null) { 918 return; 919 } 920 switch(msg.what) { 921 case NATIVE_EVENT_MARKER: 922 synchronized (mMarkerListenerLock) { 923 if (mAudioTrack.mMarkerListener != null) { 924 mAudioTrack.mMarkerListener.onMarkerReached(mAudioTrack); 925 } 926 } 927 break; 928 case NATIVE_EVENT_NEW_POS: 929 synchronized (mPeriodicListenerLock) { 930 if (mAudioTrack.mPeriodicListener != null) { 931 mAudioTrack.mPeriodicListener.onPeriodicNotification(mAudioTrack); 932 } 933 } 934 break; 935 default: 936 Log.e(TAG, "[ android.media.AudioTrack.NativeEventHandler ] " + 937 "Unknown event type: " + msg.what); 938 break; 939 } 940 } 941 } 942 943 944 //--------------------------------------------------------- 945 // Java methods called from the native side 946 //-------------------- 947 @SuppressWarnings("unused") 948 private static void postEventFromNative(Object audiotrack_ref, 949 int what, int arg1, int arg2, Object obj) { 950 //logd("Event posted from the native side: event="+ what + " args="+ arg1+" "+arg2); 951 AudioTrack track = (AudioTrack)((WeakReference)audiotrack_ref).get(); 952 if (track == null) { 953 return; 954 } 955 956 if (track.mNativeEventHandler != null) { 957 Message m = track.mNativeEventHandler.obtainMessage(what, arg1, arg2, obj); 958 track.mNativeEventHandler.sendMessage(m); 959 } 960 961 } 962 963 964 //--------------------------------------------------------- 965 // Native methods called from the Java side 966 //-------------------- 967 968 private native final int native_setup(Object audiotrack_this, 969 int streamType, int sampleRate, int nbChannels, int audioFormat, 970 int buffSizeInBytes, int mode); 971 972 private native final void native_finalize(); 973 974 private native final void native_release(); 975 976 private native final void native_start(); 977 978 private native final void native_stop(); 979 980 private native final void native_pause(); 981 982 private native final void native_flush(); 983 984 private native final int native_write_byte(byte[] audioData, 985 int offsetInBytes, int sizeInBytes, int format); 986 987 private native final int native_write_short(short[] audioData, 988 int offsetInShorts, int sizeInShorts, int format); 989 990 private native final int native_reload_static(); 991 992 private native final int native_get_native_frame_count(); 993 994 private native final void native_setVolume(float leftVolume, float rightVolume); 995 996 private native final void native_set_playback_rate(int sampleRateInHz); 997 private native final int native_get_playback_rate(); 998 999 private native final int native_set_marker_pos(int marker); 1000 private native final int native_get_marker_pos(); 1001 1002 private native final int native_set_pos_update_period(int updatePeriod); 1003 private native final int native_get_pos_update_period(); 1004 1005 private native final int native_set_position(int position); 1006 private native final int native_get_position(); 1007 1008 private native final int native_set_loop(int start, int end, int loopCount); 1009 1010 static private native final int native_get_output_sample_rate(); 1011 static private native final int native_get_min_buff_size( 1012 int sampleRateInHz, int channelConfig, int audioFormat); 1013 1014 1015 //--------------------------------------------------------- 1016 // Utility methods 1017 //------------------ 1018 1019 private static void logd(String msg) { 1020 Log.d(TAG, "[ android.media.AudioTrack ] " + msg); 1021 } 1022 1023 private static void loge(String msg) { 1024 Log.e(TAG, "[ android.media.AudioTrack ] " + msg); 1025 } 1026 1027} 1028