Audio not being sent in RTP

Question

Hi,
I'm developing a simple RTP application for capturing and Transmitting live audio. I have used [AVTransmit2|http://java.sun.com/javase/technologies/desktop/media/jmf/2.1.1/solutions/AVTransmit2.java] at the sender side and [AVReceive2|http://java.sun.com/javase/technologies/desktop/media/jmf/2.1.1/solutions/AVReceive2.java] at the receiver side. Everything is working fine when I try to transmit a wav file. But, when I try to capture live audio from the Mic and try to transmit, there is no audio at the receiver side.
I have used the following code to create a MediaLocator for the microphone.
     public static MediaLocator createLocator(){
          CaptureDeviceInfo captureDeviceInfo = null;
          Vector captureDevices=null;
          captureDevices = CaptureDeviceManager.getDeviceList(null);
          System.out.println(
                    "- number of capture devices: " + captureDevices.size());
          for (int i = 0; i < captureDevices.size(); i++) {
               captureDeviceInfo = (CaptureDeviceInfo) captureDevices.elementAt(i);
               System.out.println(
                         "    - name of the capture device: " + captureDeviceInfo.getName());
               Format[] formatArray = captureDeviceInfo.getFormats();
               for (int j = 0; j < formatArray.length; j++) {
                    Format format = formatArray[j];
                    if (format instanceof AudioFormat) {
                         System.out.println(
                                   "         - format accepted by this AUDIO device: "
                                   + format.toString().trim());
                    } else
                         System.out.println("         - format of type UNKNOWN");
          if (captureDeviceInfo!=null){
               MediaLocator audioLocator = captureDeviceInfo.getLocator();
               return audioLocator;
          return null;
     }I've used this to initialize and start the transmitter:
MediaLocator locator = createLocator();
AVTransmit2 at = new AVTransmit2(locator, "10.0.0.226", "42050");
String result = at.start();Is this the correct way to capture live audio? Please advise me if my approach is wrong.
At the receiver side, I get the notification that a new participant has joined. Then it keeps on waiting for the RTP packets to arrive and finally gets timed out.
- Waiting for RTP data to arrive...
- Waiting for RTP data to arrive...I have not made any changes to AVTransmit2 or AVReceive2. Both systems are intel Macs running Snow Leopard. I tried to use other java application to capture live audio and its working fine. I don't know how to create a datasource or Medialocator out of it. :(

Answer 1

Thanx for replying, captfoss. :)
Actually, in the code for getting the media locator I had put in some extra redundant lines just to print out the list of formats supported by the devices. Other than that they don't do anything useful. In this mac, javasound://44100 is the only device detected. So, I use it directly(the first device).
I have tried with javasound://0 , but still no luck. Any wav file is transmitted and received successfully. Is it anything related to this OS? I searched here and read that there might be issues in mac jvm not working as expected with capture devices. I don't have any idea on how to proceed. Are there any workarounds? I mean, I had used another code from an open-source java project for rtp transmission. They were using TargetDataLine and PipedOutputStream class for capturing audio and doing custom encoding in to ULAW and sending it. Its working fine with AVReceive2. Its not able to identify the stream owner, but still there is a voice path. Can I create a custom datasource from it?
Sorry, for asking too many questions, but I'm a little bit excited as well as disappointed...