Implementing an AoIP(Audio Over IP) using AudioRecord and AudioTrack

Question

I want to make an app for my project. It looks like an Android Calling Application which can send voice through IP Address of and Android Phone inside the network. But my problem is I cannot receive the Audio. My Audio Record works fine.

Here is my code:

MainActivity.java

import java.net.DatagramSocket;
import java.util.ArrayList;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

import com.example.voip.Microphone;
import com.example.voip.Speaker;
public class MainActivity extends Activity {
     DatagramSocket sock = null;
     ArrayList<String> on = null;
     Button btnStart;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        android.os.Process.setThreadPriority(android.os.Process.THREAD_PRIORITY_URGENT_AUDIO);
        btnStart = (Button) findViewById(R.id.btnStart);
        btnStart.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {
                disp();
            }
        });
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }

    public void disp(){
        on = new ArrayList<String>();
           on.add("192.168.1.103");
            try{
                sock = new DatagramSocket(4003);
            }catch(Exception e){

            }
            Thread mic = new Thread(new Microphone(sock, 4003, on));
            mic.start();
    }
}

Microphone.java

import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.util.ArrayList;

import android.media.AudioFormat;
import android.media.AudioRecord;
import android.media.MediaRecorder;




public class Microphone implements Runnable{

    private DatagramSocket sock = null;
    private int port = 0;
    int buffsize = 0;
    AudioRecord ar;
    private ArrayList<String> on = null;

    public Microphone(DatagramSocket d,int recPort,ArrayList<String> joi) {
        this.sock = d;
        this.on = joi;
        this.port =recPort;
    }

    @Override
    public void run(){
        try {


            buffsize = AudioRecord.getMinBufferSize(44100, AudioFormat.CHANNEL_IN_MONO, AudioFormat.ENCODING_PCM_16BIT);
            ar = new AudioRecord(MediaRecorder.AudioSource.MIC, 44100, AudioFormat.CHANNEL_IN_MONO, AudioFormat.ENCODING_PCM_16BIT, buffsize);
            ar.startRecording();

            byte[] soundData = new byte[1];
            int bytesRead = 0;
            while (bytesRead != -1) {
                bytesRead = ar.read(soundData, 0, soundData.length);

                if (bytesRead >= 0) {
                    for (int y = 0; y < on.size(); y++) {
                        DatagramPacket pac = new DatagramPacket(soundData,soundData.length,InetAddress.getByName(on.get(y).toString()),port);
                        sock.send(pac);
                    }
                }
                Thread.sleep(0);
            }

            /*
            AudioFormat af = new AudioFormat(8000.0f, 8, 1, true, false);
            DataLine.Info info = new DataLine.Info(TargetDataLine.class, af);
            TargetDataLine microphone = (TargetDataLine) AudioSystem.getLine(info);

            microphone.open(af);
            microphone.start();

            byte[] soundData = new byte[1];
            int bytesRead = 0;
            while (bytesRead != -1) {
                bytesRead = microphone.read(soundData, 0, soundData.length);

                if (bytesRead >= 0) {
                    for (int y = 0; y < on.size(); y++) {
                        DatagramPacket pac = new DatagramPacket(soundData,
                                soundData.length,
                                InetAddress.getByName(on.getElementAt(y).toString()),
                                port);
                        sock.send(pac);
                    }
                }
                Thread.sleep(0);
            }

        } catch (Exception e) {
        }
    }
     */
        }catch(Exception e){

        }
    }

    public void setSock(DatagramSocket sock) {
        this.sock = sock;
    }

    /**
     * @param port the port to set
     */
    public void setPort(int port) {
        this.port = port;
    }

    /**
     * @param on the on to set
     */
    public void setOn(ArrayList<String> on) {
        this.on = on;
    }
}

Speaker.java

    import java.io.IOException;
    import java.net.DatagramPacket;
    import java.net.DatagramSocket;

    import android.media.AudioFormat;
    import android.media.AudioManager;
    import android.media.AudioRecord;
    import android.media.AudioTrack;
    import android.media.MediaRecorder;
    import android.net.rtp.AudioStream;

    public class Speaker implements Runnable {
         private int freq = 44100 ;

            private Thread Rthread = null;

            private AudioManager audioManager = null;
            private AudioTrack inSpeaker = null;
            byte[] buffer = new byte[freq];
        private DatagramSocket soc = null;
        DatagramPacket pack = null;
       // SourceDataLine inSpeaker = null;




        public Speaker(DatagramSocket s) {

            try {
                /*
                this.soc = s;
                AudioFormat af = new AudioFormat(8000.0f, 8, 1, true, false);
                DataLine.Info info = new DataLine.Info(SourceDataLine.class, af);
                inSpeaker = (SourceDataLine) AudioSystem.getLine(info);
                inSpeaker.open(af);
                */

                int bufferSize = AudioRecord.getMinBufferSize(freq,
                        AudioFormat.CHANNEL_CONFIGURATION_MONO,
                        AudioFormat.ENCODING_PCM_16BIT);
                inSpeaker = new AudioTrack(AudioManager.ROUTE_HEADSET, freq,
                        AudioFormat.CHANNEL_CONFIGURATION_MONO,
                        MediaRecorder.AudioEncoder.AMR_NB, bufferSize,
                        AudioTrack.MODE_STREAM);



                System.out.println("Speak");

            } catch (Exception e) {
                System.out.println(e.getMessage());
            }
        }




        public void run() {
            inSpeaker.setPlaybackRate(freq);
            int bytesRead = 1;
            byte[] inSound = new byte[1];

            inSpeaker.play();

            while (bytesRead != -1) {
                pack = new DatagramPacket(inSound, inSound.length);

                try {
                    soc.receive(pack);
                    if (bytesRead >= 0) {
                    inSpeaker.write(inSound, 0, bytesRead);

                    }

                } catch (IOException ex) {
                    System.out.println(ex.getMessage());
                }
            }
        }

        public void setSoc(DatagramSocket soc) {
            this.soc = soc;
        }



    }

Receiver.java
package com.example.call;

import java.net.DatagramSocket;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;

import com.example.voip.Speaker;

public class Receiver extends BroadcastReceiver{
DatagramSocket sock;
    @Override
    public void onReceive(Context arg0, Intent arg1) {
        // TODO Auto-generated method stub
        try{
        sock = new DatagramSocket(4003);
        }catch(Exception e){

        }
        Thread speak = new Thread(new Speaker(sock));
        speak.start();
    }

}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.call"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="16"
        android:targetSdkVersion="16" />
    <uses-permission android:name="android.permission.USE_SIP" />
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.VIBRATE" />
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
    <uses-permission android:name="android.permission.WAKE_LOCK" />
    <uses-permission android:name="android.permission.RECORD_AUDIO" />
    <uses-permission android:name="android.permission.MODIFY_AUDIO_SETTINGS"></uses-permission>

    <uses-feature android:name="android.hardware.microphone" android:required="true"/>
    <uses-feature android:name="android.hardware.wifi" android:required="true" />


    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.example.call.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <receiver android:name="com.example.call.Receiver"></receiver>
    </application>

</manifest>

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:padding="20dip">

    <ImageView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:src="@drawable/ic_launcher"
        android:scaleType="fitCenter"/>

        <TextView  
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Info"
        android:layout_weight="1.0"
        android:textSize="20dip"/>

    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content">

        <Button
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:id="@+id/btnStart"
                android:text="Start Recording"
                android:layout_weight="1.0"/>

                <Button
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:id="@+id/btnStop"
                android:text="Stop Recording"
                android:layout_weight="1.0"/>
    </LinearLayout>
</LinearLayout>

No Error at all. But I cannot receive any voice. Please help =(

Thanks in advance.

Answer 1

This code in Speaker.java is incorrect:

    int bufferSize = AudioRecord.getMinBufferSize(freq,
            AudioFormat.CHANNEL_CONFIGURATION_MONO,
            AudioFormat.ENCODING_PCM_16BIT);
    inSpeaker = new AudioTrack(AudioManager.ROUTE_HEADSET, freq,
                AudioFormat.CHANNEL_CONFIGURATION_MONO,
                MediaRecorder.AudioEncoder.AMR_NB, bufferSize,
                AudioTrack.MODE_STREAM);

It should be:

    int bufferSize = AudioTrack.getMinBufferSize(freq,
            AudioFormat.CHANNEL_OUT_MONO,
            AudioFormat.ENCODING_PCM_16BIT);
    inSpeaker = new AudioTrack(AudioManager.STREAM_MUSIC, freq,
                AudioFormat.CHANNEL_OUT_MONO,
                AudioFormat.ENCODING_PCM_16BIT, bufferSize,
                AudioTrack.MODE_STREAM);