代码分析JAVA中PCM人声音频变声处理

项目中需要用到对PCM人声音频数据进行变声处理。苦苦挣扎了一周终于找到了纯Java实现的一套框架――TarsosDSP。功能非常强大！可以实时音频处理！当然我只用到了对文件处理。实际上逻辑是一样的

TarsosDSP的GitHub地址：https://github.com/JorenSix/TarsosDSP将它整合至自己的项目工程。

具体Java工具类代码：

 /**   * 变声   * @param rawPcmInputStream 原始PCM数据输入流   * @param speedFactor 变速率 (0,2) 大于1为加快语速，小于1为放慢语速   * @param rateFactor 音调变化率 (0,2) 大于1为降低音调（深沉），小于1为提升音调（尖锐）   * @return 变声后的PCM数据输入流   */  public static InputStream speechPitchShift(final InputStream rawPcmInputStream,double speedFactor,double rateFactor) {    TarsosDSPAudioFormat format = new TarsosDSPAudioFormat(16000,16,1,true,false);    AudioInputStream inputStream = new AudioInputStream(rawPcmInputStream, JVMAudioInputStream.toAudioFormat(format),AudioSystem.NOT_SPECIFIED);    JVMAudioInputStream stream = new JVMAudioInputStream(inputStream);    WaveformSimilarityBasedOverlapAdd w = new WaveformSimilarityBasedOverlapAdd(WaveformSimilarityBasedOverlapAdd.Parameters.speechDefaults(speedFactor, 16000));    int inputBufferSize = w.getInputBufferSize();    int overlap = w.getOverlap();    AudioDispatcher dispatcher = new AudioDispatcher(stream, inputBufferSize ,overlap);    w.setDispatcher(dispatcher);    AudioOutputToByteArray out = new AudioOutputToByteArray();    dispatcher.addAudioProcessor(w);    dispatcher.addAudioProcessor(new RateTransposer(rateFactor));    dispatcher.addAudioProcessor(out);    dispatcher.run();    return new ByteArrayInputStream(out.getData());  }

其中数据转录器(AudioOutputToByteArray)代码如下：

public class AudioOutputToByteArray implements AudioProcessor {  private boolean isDone = false;  private byte[] out = null;  private ByteArrayOutputStream bos;  public AudioOutputToByteArray() {    bos = new ByteArrayOutputStream();  }  public byte[] getData() {    while (!isDone && out == null) {      try {        Thread.sleep(10);      } catch (InterruptedException ignored) {}    }    return out;  }  @Override  public boolean process(AudioEvent audioEvent) {    bos.write(audioEvent.getByteBuffer(),0,audioEvent.getByteBuffer().length);    return true;  }  @Override  public void processingFinished() {    out = bos.toByteArray().clone();    bos = null;    isDone = true;  }}

可以通过这个工具方法播放音频：

 /**   * 播放PCM   *   * 不要在非桌面环境调用。。。鬼知道会发生什么   * @param rawPcmInputStream 原始PCM数据输入流   * @throws LineUnavailableException   */  public static void play(final InputStream rawPcmInputStream) throws LineUnavailableException {    TarsosDSPAudioFormat format = new TarsosDSPAudioFormat(16000,16,1,true,false);    AudioInputStream inputStream = new AudioInputStream(rawPcmInputStream, JVMAudioInputStream.toAudioFormat(format),AudioSystem.NOT_SPECIFIED);    JVMAudioInputStream stream = new JVMAudioInputStream(inputStream);    AudioDispatcher dispatcher = new AudioDispatcher(stream, 1024 ,0);    dispatcher.addAudioProcessor(new AudioPlayer(format,1024));    dispatcher.run();  }