android – 我怎么能播放pcm文件

以下代码应记录音频并以PCM格式存储到SD卡中.
代码正在与我合作,但PCM文件无法播放!!!!

我从这个链接获得了这个代码…. Android : recording audio using audiorecord class play as fast forwarded

我需要播放PCM文件我该怎么做？??????

public class Audio_Record extends Activity {
private static final int RECORDER_SAMPLERATE = 8000;
private static final int RECORDER_CHANNELS = AudioFormat.CHANNEL_IN_MONO;
private static final int RECORDER_AUDIO_ENCODING = AudioFormat.ENCODING_PCM_16BIT;
private AudioRecord recorder = null;
private Thread recordingThread = null;
private boolean isRecording = false;

 @Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);

setButtonHandlers();
enableButtons(false);

int bufferSize = AudioRecord.getMinBufferSize(RECORDER_SAMPLERATE,RECORDER_CHANNELS,RECORDER_AUDIO_ENCODING);

System.out.println("BUFFER SIZE VALUE IS " + bufferSize);

 }

       private void setButtonHandlers() {
 ((Button) findViewById(R.id.btnStart)).setOnClickListener(btnClick);
((Button) findViewById(R.id.btnStop)).setOnClickListener(btnClick);
    }

   private void enableButton(int id,boolean isEnable) {
((Button) findViewById(id)).setEnabled(isEnable);
    }

private void enableButtons(boolean isRecording) {
enableButton(R.id.btnStart,!isRecording);
enableButton(R.id.btnStop,isRecording);
   }

  int BufferElements2Rec = 1024; // want to play 2048 (2K) since 2 bytes we
                            // use only 1024
  int BytesPerElement = 2; // 2 bytes in 16bit format

   private void startRecording() {

recorder = new AudioRecord(MediaRecorder.AudioSource.MIC,RECORDER_SAMPLERATE,RECORDER_AUDIO_ENCODING,BufferElements2Rec * BytesPerElement);

recorder.startRecording();
isRecording = true;

recordingThread = new Thread(new Runnable() {

      public void run() {

        writeAudioDataToFile();

    }
},"AudioRecorder Thread");
recordingThread.start();
    }

private byte[] short2byte(short[] sData) {
int shortArrsize = sData.length;
byte[] bytes = new byte[shortArrsize * 2];

for (int i = 0; i < shortArrsize; i++) {
    bytes[i * 2] = (byte) (sData[i] & 0x00FF);
    bytes[(i * 2) + 1] = (byte) (sData[i] >> 8);
    sData[i] = 0;
}
return bytes;

  }

  private void writeAudioDataToFile() {
// Write the output audio in byte

String filePath = "/sdcard/voice8K16bitmono.pcm";
short sData[] = new short[BufferElements2Rec];

FileOutputStream os = null;
try {
    os = new FileOutputStream(filePath);
} catch (FileNotFoundException e) {
    e.printStackTrace();
}

while (isRecording) {
    // gets the voice output from microphone to byte format

    recorder.read(sData,BufferElements2Rec);
    System.out.println("Short wirting to file" + sData.toString());
    try {
        // // writes the data to file from buffer
        // // stores the voice buffer

        byte bData[] = short2byte(sData);

        os.write(bData,BufferElements2Rec * BytesPerElement);
    } catch (IOException e) {
        e.printStackTrace();
    }
}

try {
    os.close();
} catch (IOException e) {
    e.printStackTrace();
}
}

private void stopRecording() {
// stops the recording activity
if (null != recorder) {
    isRecording = false;

    recorder.stop();
    recorder.release();

    recorder = null;
    recordingThread = null;
}
 }

private View.OnClickListener btnClick = new View.OnClickListener() {
public void onClick(View v) {
    switch (v.getId()) {
    case R.id.btnStart: {
        enableButtons(true);
        startRecording();
        break;
    }
    case R.id.btnStop: {
        enableButtons(false);
        stopRecording();
        break;
    }
    }
}
 };

  @Override
  public boolean onKeyDown(int keyCode,KeyEvent event) {

if (keyCode == KeyEvent.KEYCODE_BACK) {

    finish();
}
return super.onKeyDown(keyCode,event);
 }
}

解决方法

Android的媒体播放器默认不播放PCM文件.或

>将其从SD卡复制到计算机并在那里播放
>使用AudioTrack编写自己的播放器
>安装播放PCM的应用程序

这是一个关于如何使用AudioTrack类播放PCM的教程：(http://jongladwin.blogspot.co.uk/2010/03/android-play-pcmwav-audio-buffer-using.html)

Windows Media Player应该能够播放PCM,这里提到了一些替代方案：(http://www.makeuseof.com/answers/play-pcm-file-pc/)

我猜Android上的大多数大型音乐播放器应用都支持PCM.