通过Android上的套接字接收实时音频数据

Question

我编写了一个应用程序，通过WiFi连接到Rpi上的网络套接字，并已成功向客户端和服务器发送数据（如字符串）。下一步是让客户端，我的手机在这种情况下，实时接收和播放从服务器发送的音频数据。

到目前为止，我已经声明了套接字和音频变量。一旦一个按钮被击中，异步任务“收听”就开始了。我知道它可以连接到插座。之后，我试图打开一个输入流并将其输入缓冲区，然后实时播放该缓冲区。

我想我很接近搞清楚，但我认为我没有把它说得很对。我在代码中标记了TODO不确定的区域。

public class MainActivity extends AppCompatActivity { 
//audio variables 
static final int sampleFreq = 44100; 
static final int channelConfig = AudioFormat.CHANNEL_OUT_MONO; 
static final int audioEncoding = AudioFormat.ENCODING_PCM_16BIT; 
static final int streamType = STREAM_MUSIC; 
static final int audioMode = MODE_STREAM; 
static final int bufferSize = getMinBufferSize(sampleFreq, channelConfig, audioMode); 

//socket variables 
public Socket mySocket; 
private int SERVERPORT = 33333; 
private static final String SERVER_IP = "172.24.1.1"; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 
    SharedPreferences sharedPref = PreferenceManager.getDefaultSharedPreferences(this); 
} 

public void onClickListen(View view) { 
    //call async task 
    new Listen().execute(); 
} 


private class Listen extends AsyncTask<Void, Void, Void> { 
    @Override 
    protected Void doInBackground(Void... params) { 

     try { 
      //get IP and port number 
      InetAddress serverAddr = InetAddress.getByName(SERVER_IP); 
      Log.d(debugStr, "In initial listen connect"); 
      //create socket 
      mySocket = new Socket(serverAddr, SERVERPORT); 

     } catch (UnknownHostException e1) { 
      e1.printStackTrace(); 
     } catch (IOException e1) { 
      e1.printStackTrace(); 
     } finally { 
      if (mySocket == null) { 
       str1 = "Socket became null, listener"; 
       return null; 
      } 



//TODO here is all the new audio stuff 
      try { 
       //creates buffer to hold incoming audio data 
       byte [] audioBuffer = new byte[4096]; 

       //creates input stream readers to read incoming data 
       BufferedInputStream myBis = new BufferedInputStream(mySocket.getInputStream()); 
       DataInputStream myDis = new DataInputStream(myBis); 
       Log.d(debugStr, "Input created, listener"); 

       // Read the file into the music array. 
       int i = 0; 

       //TODO unsure of while loop condition 
       while (myDis.read() != -1) { 
        //since incoming audio is unknown size, use estimated buffer size 
        audioBuffer[bufferSize-1-i] = myDis.readByte(); 
        i++; 
       } 
       //create audio track object 
       AudioTrack myAudioTrack = new AudioTrack(streamType, sampleFreq, channelConfig, audioEncoding, bufferSize, audioMode); 

       //TODO write audio data to somewhere? 
       //TODO should this be in a while loop for live stream? 
       //TODO will this actually play the audio? 
       myAudioTrack.write(audioBuffer, 0, bufferSize); 

       //close input streams 
       myDis.close(); 
       myBis.close(); 


      } catch (IOException e1) { 
       e1.printStackTrace(); 
      } 
      try { 
       mySocket.close(); 
      } catch (IOException e1) { 
       e1.printStackTrace(); 
      } 
      return null; 
     } 
    } 
} 
} 

我不认为我的while循环的条件是正确的，或者是甚至从输入流中读取数据的正确方法。我也认为audioTrack.write应该在while循环中，如果这实际上使音频播放。

任何帮助或澄清非常感谢！

Answer 1

我想通了。

byte [] audioBuffer = new byte[4096]; 

       //creates input stream readers to read incoming data 
       BufferedInputStream myBis = new BufferedInputStream(mySocket.getInputStream()); 
       DataInputStream myDis = new DataInputStream(myBis); 

       Log.d(debugStr, "Input created, listener"); 
       AudioTrack myAudioTrack = new AudioTrack(streamType, sampleFreq, channelConfig, audioEncoding, bufferSize, audioMode); 
       //Log.d(debugStr, String.valueOf(mySocket.getInputStream().read(audioBuffer))); 

       Log.d(debugStr, "track made"); 
       // Read the file into the music array. 
       int i = 0; 
       //TODO unsure of while loop condition 
       while (mySocket.getInputStream().read(audioBuffer) != -1) { 

        audioBuffer[audioBuffer.length-1-i] = myDis.readByte(); 
        myAudioTrack.play(); 
        myAudioTrack.write(audioBuffer, 0, audioBuffer.length); 
        i++; 
       } 



       //close input streams 
       myDis.close(); 
       myBis.close();