Enregistrement audio Android sur le serveur via des problèmes de lecture UDP

Question

J'essaie de créer une application Android simple qui diffuse l'audio d'un microphone en direct sur un serveur pour la lecture. La lecture qui en résulte semble étrange, avec de grandes lacunes dans l’audio. Est-ce que quelqu'un sait ce que je fais mal?

EDIT: résolu. Il s'avère que je supposais que chaque tampon entrant serait complètement rempli, hypothèse erronée de ma part.

Voici mon activité:

public class MainActivity extends Activity {
    private static String TAG = "AudioClient";

    // the server information
    private static final String SERVER = "xx.xx.xx.xx";
    private static final int PORT = 50005;

    // the audio recording options
    private static final int RECORDING_RATE = 44100;
    private static final int CHANNEL = AudioFormat.CHANNEL_IN_MONO;
    private static final int FORMAT = AudioFormat.ENCODING_PCM_16BIT;

    // the button the user presses to send the audio stream to the server
    private Button sendAudioButton;

    // the audio recorder
    private AudioRecord recorder;

    // the minimum buffer size needed for audio recording
    private static int BUFFER_SIZE = AudioRecord.getMinBufferSize(
            RECORDING_RATE, CHANNEL, FORMAT);

    // are we currently sending audio data
    private boolean currentlySendingAudio = false;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Log.i(TAG, "Creating the Audio Client with minimum buffer of "
                + BUFFER_SIZE + " bytes");

        // set up the button
        sendAudioButton = (Button) findViewById(R.id.start_button);
        sendAudioButton.setOnTouchListener(new OnTouchListener() {

            @Override
            public boolean onTouch(View v, MotionEvent event) {

                switch (event.getAction()) {

                case MotionEvent.ACTION_DOWN:
                    startStreamingAudio();
                    break;

                case MotionEvent.ACTION_UP:
                    stopStreamingAudio();
                    break;
                }

                return false;
            }
        });
    }

    private void startStreamingAudio() {

        Log.i(TAG, "Starting the audio stream");
        currentlySendingAudio = true;
        startStreaming();
    }

    private void stopStreamingAudio() {

        Log.i(TAG, "Stopping the audio stream");
        currentlySendingAudio = false;
        recorder.release();
    }

    private void startStreaming() {

        Log.i(TAG, "Starting the background thread to stream the audio data");

        Thread streamThread = new Thread(new Runnable() {

            @Override
            public void run() {
                try {

                    Log.d(TAG, "Creating the datagram socket");
                    DatagramSocket socket = new DatagramSocket();

                    Log.d(TAG, "Creating the buffer of size " + BUFFER_SIZE);
                    byte[] buffer = new byte[BUFFER_SIZE];

                    Log.d(TAG, "Connecting to " + SERVER + ":" + PORT);
                    final InetAddress serverAddress = InetAddress
                            .getByName(SERVER);
                    Log.d(TAG, "Connected to " + SERVER + ":" + PORT);

                    Log.d(TAG, "Creating the reuseable DatagramPacket");
                    DatagramPacket packet;

                    Log.d(TAG, "Creating the AudioRecord");
                    recorder = new AudioRecord(MediaRecorder.AudioSource.MIC,
                            RECORDING_RATE, CHANNEL, FORMAT, BUFFER_SIZE * 10);

                    Log.d(TAG, "AudioRecord recording...");
                    recorder.startRecording();

                    while (currentlySendingAudio == true) {

                        // read the data into the buffer
                        int read = recorder.read(buffer, 0, buffer.length);

                        // place contents of buffer into the packet
                        packet = new DatagramPacket(buffer, read,
                            serverAddress, PORT);

                        // send the packet
                        socket.send(packet);
                    }

                    Log.d(TAG, "AudioRecord finished recording");

                } catch (Exception e) {
                    Log.e(TAG, "Exception: " + e);
                }
            }
        });

        // start the thread
        streamThread.start();
    }
}

Voici mon code côté serveur:

class Server {

    AudioInputStream audioInputStream;
    static AudioInputStream ais;
    static AudioFormat format;
    static boolean status = true;
    static int port = 50005;
    static int sampleRate = 11025;
    static int bufferSize = 9728;

    static Long lastTime;
    static long totalBytesReceived = 0L;

    private static final int audioStreamBufferSize = bufferSize * 20;
    static byte[] audioStreamBuffer = new byte[audioStreamBufferSize];
    private static int audioStreamBufferIndex = 0;

    public static void main(String args[]) throws Exception {

        Log("Starting the AudioServer...");

        Log("Creating the datagram socket on port " + port + "...");
        DatagramSocket serverSocket = new DatagramSocket(null);
        serverSocket.setReuseAddress(true);
        serverSocket.bind(new InetSocketAddress(port));

        Log("Creating the buffer to hold the received data of size "
                + bufferSize + "...");
        byte[] receiveData = new byte[bufferSize];

        Log("Setting the audio rate to " + sampleRate + "hz...");
        format = new AudioFormat(sampleRate, 16, 1, true, false);

        Log("Ready to receive audio data");
        while (status == true) {

            DatagramPacket receivePacket = new DatagramPacket(receiveData,
                    receiveData.length);
            serverSocket.receive(receivePacket);
            bufferAudioForPlayback(receivePacket.getData(),
                    receivePacket.getOffset(), receivePacket.getLength());
        }

        serverSocket.close();
    }

    private static void bufferAudioForPlayback(byte[] buffer, int offset,
            int length) {

        byte[] actualBytes = new byte[length];

        for (int i = 0; i < length; i++) {
            actualBytes[i] = buffer[i];
        }

        for (byte sample : actualBytes) {

            int percentage = (int) (((double) audioStreamBufferIndex / (double) audioStreamBuffer.length) * 100.0);
            Log("buffer is " + percentage + "% full");

            audioStreamBuffer[audioStreamBufferIndex] = sample;
            audioStreamBufferIndex++;
            Log("Buffer " + audioStreamBufferIndex + " / "
                    + audioStreamBuffer.length + "    " + percentage);

            if (audioStreamBufferIndex == audioStreamBuffer.length - 1) {
                toSpeaker(audioStreamBuffer);
                audioStreamBufferIndex = 0;
                System.exit(0);
            }
        }
    }

    private static void Log(String log) {
        System.out.println(log);
    }

    public static void toSpeaker(byte soundbytes[]) {
        try {

            DataLine.Info dataLineInfo = new DataLine.Info(
                    SourceDataLine.class, format);
            SourceDataLine sourceDataLine = (SourceDataLine) AudioSystem
                    .getLine(dataLineInfo);

            sourceDataLine.open(format);

            FloatControl volumeControl = (FloatControl) sourceDataLine
                    .getControl(FloatControl.Type.MASTER_GAIN);
            volumeControl.setValue(100.0f);

            sourceDataLine.start();
            sourceDataLine.open(format);
            sourceDataLine.start();
            sourceDataLine.write(soundbytes, 0, soundbytes.length);
            sourceDataLine.drain();
            sourceDataLine.close();
        } catch (Exception e) {
            System.out.println("Error with audio playback: " + e);
            e.printStackTrace();
        }
    }
}

Enfin, voici le fichier XML de ressource pour l'activité principale:

<?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="@string/app_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="@string/start_recording"
                Android:layout_weight="1.0"/>

                <Button
                Android:layout_width="wrap_content"
                Android:layout_height="wrap_content"
                Android:id="@+id/btnStop"
                Android:text="@string/stop_recording"
                Android:layout_weight="1.0"/>
    </LinearLayout>
</LinearLayout>

EDIT: la lecture audio suh-suh-suh-suh-o-ou-ou-ou-nds-nds-ds aime ça.

Answer 1

Voici quelque chose que vous pouvez essayer, au lieu de:

// read the data into the buffer
recorder.read(buffer, 0, buffer.length);

// place contents of buffer into the packet
packet = new DatagramPacket(buffer, buffer.length, serverAddress, PORT);

Ne vous attendez pas à recevoir le tampon de lecture intégral de recorder mais utilisez plutôt la valeur de lecture réelle

// read the data into the buffer
int read = recorder.read(buffer, 0, buffer.length);

// place contents of buffer into the packet
packet = new DatagramPacket(buffer, read, serverAddress, PORT);

Ou quelque chose de semblable.

Answer 2

Merci pour le post Joshua .... une aide précieuse pour les nouvelles abeilles :)

volumeControl.setValue(volumeControl.getMaximum());

removes illegalStateException at Server

et permission dans le client Android

<uses-permission Android:name="Android.permission.RECORD_AUDIO"/>