實時錄製和播放android延遲問題

Question

我正在使用Live Audio Recording and Playing in Android and Thread & callback handling這個例子來播放回放，但播放錄製的音頻時延遲非常小。如何解決它。

boolean m_isRun=true; 
public void loopback() { 
     // Prepare the AudioRecord & AudioTrack 
     try { 
      buffersize = AudioRecord.getMinBufferSize(SAMPLE_RATE, 
        AudioFormat.CHANNEL_CONFIGURATION_MONO, 
        AudioFormat.ENCODING_PCM_16BIT); 

      if (buffersize <= BUF_SIZE) { 
       buffersize = BUF_SIZE; 
      } 
      Log.i(LOG_TAG,"Initializing Audio Record and Audio Playing objects"); 

      m_record = new AudioRecord(MediaRecorder.AudioSource.MIC, 
        SAMPLE_RATE, AudioFormat.CHANNEL_CONFIGURATION_MONO, 
        AudioFormat.ENCODING_PCM_16BIT, buffersize * 1); 

      m_track = new AudioTrack(AudioManager.STREAM_ALARM, 
        SAMPLE_RATE, AudioFormat.CHANNEL_CONFIGURATION_MONO, 
        AudioFormat.ENCODING_PCM_16BIT, buffersize * 1, 
        AudioTrack.MODE_STREAM); 

      m_track.setPlaybackRate(SAMPLE_RATE); 
     } catch (Throwable t) { 
      Log.e("Error", "Initializing Audio Record and Play objects Failed "+t.getLocalizedMessage()); 
     } 

     m_record.startRecording(); 
     Log.i(LOG_TAG,"Audio Recording started"); 
     m_track.play(); 
     Log.i(LOG_TAG,"Audio Playing started"); 

     while (m_isRun) { 
      m_record.read(buffer, 0, BUF_SIZE); 
      m_track.write(buffer, 0, buffer.length); 
     } 

     Log.i(LOG_TAG, "loopback exit"); 
    } 

    private void do_loopback() { 
     m_thread = new Thread(new Runnable() { 
      public void run() { 
       loopback(); 
      } 
     }); 

Answer 1

它可以通過Android的Opensl實現。但Android正在努力實現它。

下面是爲數不多的教程，這將有助於你

https://code.google.com/p/opensl-soundpool/

https://code.google.com/p/high-performance-audio/