Voice chat not working.

Question

Hello,
I was just trying the code given in JMF documentation for voice chat. When i ran the below given code, it doesn't throw any error but after running this program when i speak anything into my microphone i am unable to hear anything. What can be the problem?
package sendmicrophonedata;
import java.io.IOException;
import java.util.Vector;
import javax.media.CaptureDeviceInfo;
import javax.media.CaptureDeviceManager;
import javax.media.DataSink;
import javax.media.Manager;
import javax.media.MediaLocator;
import javax.media.NoProcessorException;
import javax.media.NotRealizedError;
import javax.media.Processor;
import javax.media.control.FormatControl;
import javax.media.control.TrackControl;
import javax.media.format.AudioFormat;
import javax.media.protocol.ContentDescriptor;
import javax.media.protocol.DataSource;
public class Main {
     * @param args the command line arguments
    public static void main(String[] args) {
       // First find a capture device that will capture linear audio
        // data at 8bit 8Khz
        AudioFormat format= new AudioFormat(AudioFormat.LINEAR,
                                            8000,
                                            8,
                                            1);
        Vector devices= CaptureDeviceManager.getDeviceList( format);
        CaptureDeviceInfo di= null;
        if (devices.size() > 0) {
             di = (CaptureDeviceInfo) devices.elementAt( 0);
        else {
            // exit if we could not find the relevant capturedevice.
            System.exit(-1);
        // Create a processor for this capturedevice & exit if we
        // cannot create it
        Processor processor = null;
        try {
             processor = Manager.createProcessor(di.getLocator());
        } catch (IOException e) {
            System.exit(-1);
        } catch (NoProcessorException e) {
            System.exit(-1);
       // configure the processor
       processor.configure();
       // block until it has been configured
       processor.setContentDescriptor(
           new ContentDescriptor( ContentDescriptor.RAW));
       TrackControl track[] = processor.getTrackControls();
       boolean encodingOk = false;
       // Go through the tracks and try to program one of them to
       // output gsm data.
        for (int i = 0; i < track.length; i++) {
            if (!encodingOk && track[i] instanceof FormatControl) {
            if (((FormatControl)track).
setFormat( new AudioFormat(AudioFormat.GSM_RTP,
8000,
8,
1)) == null) {
track[i].setEnabled(false);
else {
encodingOk = true;
} else {
// we could not set this track to gsm, so disable it
track[i].setEnabled(false);
// At this point, we have determined where we can send out
// gsm data or not.
// realize the processor
if (encodingOk) {
processor.realize();
// block until realized.
// get the output datasource of the processor and exit
// if we fail
DataSource ds = null;
try {
ds = processor.getDataOutput();
} catch (NotRealizedError e) {
System.exit(-1);
// hand this datasource to manager for creating an RTP
// datasink our RTP datasimnk will multicast the audio
try {
String url= "rtp://192.168.1.255:8888/audio";
MediaLocator m = new MediaLocator(url);
DataSink d = Manager.createDataSink(ds, m);
d.open();
d.start();
} catch (Exception e) {
System.exit(-1);

Answer 1

LaalaPanchal wrote:
Hello,
I was just trying the code given in JMF documentation for voice chat. When i ran the below given code, it doesn't throw any error but after running this program when i speak anything into my microphone i am unable to hear anything. What can be the problem?Why exactly are you expecting to hear anything? You don't have anything in your code to render sound, so why're you expecting it to?