Streaming voice between Android Phones over WiFi
I'm trying to stream audio from the mic from 1 Android to another over WiFi. After looking at some examples I made 2 applications with a single activity in each, 1 to capture and send audio and the other to receive.
I've used the Audiorecord and Audiotrack classes to capture and play. However, i just hear some crackling sound (which has now stopped after i made some changes though i reverted back)
The activity to send voice.
public class VoiceSenderActivity extends Activity {
private EditText target;
private TextView streamingLabel;
private Button startButton,stopButton;
public byte[] buffer;
public static DatagramSocket socket;
private int port=50005; //which port??
AudioRecord recorder;
//Audio Configuration.
private int sampleRate = 8000; //How much will be ideal?
private int channelConfig = AudioFormat.CHANNEL_CONFIGURATION_MONO;
private int audioFormat = AudioFormat.ENCODING_PCM_16BIT;
private boolean status = true;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
target = (EditText) findViewById (R.id.target_IP);
streamingLabel = (TextView) findViewById(R.id.streaming_label);
startButton = (Button) findViewById (R.id.start_button);
stopButton = (Button) findViewById (R.id.stop_button);
streamingLabel.setText("Press Start! to begin");
startButton.setOnClickListener (startListener);
stopButton.setOnClickListener (stopListener);
}
private final OnClickListener stopListener = new OnClickListener() {
@Override
public void onClick(View arg0) {
status = false;
recorder.release();
Log.d("VS","Recorder released");
}
};
private final OnClickListener startListener = new OnClickListener() {
@Override
public void onClick(View arg0) {
status = true;
startStreaming();
}
};
public void startStreaming() {
Thread streamThread = new Thread(new Runnable() {
@Override
public void run() {
try {
int minBufSize = AudioRecord.getMinBufferSize(sampleRate, channelConfig, audioFormat);
DatagramSocket socket = new DatagramSocket();
Log.d("VS", "Socket Created");
byte[] buffer = new byte[minBufSize];
Log.d("VS","Buffer created of size " + minBufSize);
DatagramPacket packet;
final InetAddress destination = InetAddress.getByName(target.getText().toString());
Log.d("VS", "Address retrieved");
recorder = new AudioRecord(MediaRecorder.AudioSource.MIC,sampleRate,channelConfig,audioFormat,minBufSize);
Log.d("VS", "Recorder initialized");
recorder.startRecording();
while(status == true) {
//reading data from MIC into buffer
minBufSize = recorder.read(buffer, 0, buffer.length);
//putting buffer in the packet
packet = new DatagramPacket (buffer,buffer.length,destination,port);
socket.send(packet);
}
} catch(UnknownHostException e) {
Log.e("VS", "UnknownHostException");
} catch (IOException e) {
Log.e("VS", "IOException");
}
}
});
streamThread.start();
}
}
The activity to receive voice
public class VoiceReceiverActivity extends Activity {
private Button receiveButton,stopButton;
public static DatagramSocket socket;
private AudioTrack speaker;
//Audio Configuration.
private int sampleRate = 8000; //How much will be ideal?
private int channelConfig = AudioFormat.CHANNEL_CONFIGURATION_MONO;
private int audioFormat = AudioFormat.ENCODING_PCM_16BIT;
private boolean status = true;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
receiveButton = (Button) findViewById (R.id.receive_button);
stopButton = (Button) findViewById (R.id.stop_button);
findViewById(R.id.receive_label);
receiveButton.setOnClickListener(receiveListener);
stopButton.setOnClickListener(stopListener);
}
private final OnClickListener stopListener = new OnClickListener() {
@Override
public void onClick(View v) {
status = false;
speaker.release();
Log.d("VR","Speaker released");
}
};
private final OnClickListener receiveListener = new OnClickListener() {
@Override
public void onClick(View arg0) {
status = true;
startReceiving();
}
};
public void startReceiving() {
Thread receiveThread = new Thread (new Runnable() {
@Override
public void run() {
try {
DatagramSocket socket = new DatagramSocket(50005);
Log.d("VR", "Socket Created");
byte[] buffer = new byte[256];
//minimum buffer size. need to be careful. might cause problems. try setting manually if any problems faced
int minBufSize = AudioRecord.getMinBufferSize(sampleRate, channelConfig, audioFormat);
speaker = new AudioTrack(AudioManager.STREAM_MUSIC,sampleRate,channelConfig,audioFormat,minBufSize,AudioTrack.MODE_STREAM);
speaker.play();
while(status == true) {
try {
DatagramPacket packet = new DatagramPacket(buffer,buffer.length);
socket.receive(packet);
Log.d("VR", "Packet Received");
//reading content from packet
buffer=packet.getData();
Log.d("VR", "Packet data read into buffer");
//sending data to the Audiotrack obj i.e. speaker
speaker.write(buffer, 0, minBufSize);
Log.d("VR", "Writing buffer content to speaker");
} catch(IOException e) {
Log.e("VR","IOException");
}
}
} catch (SocketException e) {
Log.e("VR", "SocketException");
}
}
});
receiveThread.start();
}
}
I used wireshark to check if the packets are being sent and i can see the packets. The source however, is the MAC address of the sending device and destination too something like a physical address. Not sure if this is relevant though.
So what's the problem with?
Answer
Hey there is an Open Source library called "Libstreaming" that is used for streaming voice/video over the network using WIFI. Just Have a look at it:
https://github.com/fyhertz/libstreaming
There are also some examples provided, kindly have a look at it:
https://github.com/fyhertz/libstreaming-examples
I have used the library to Stream RTSP Audio over the network,hope it may be useful.