Acquisizione di flussi audio in JAVA

javax.sound.sampled pacchetto dovrebbe avere tutto il necessario.

Esempio:

    int duration = 5; // sample for 5 seconds
    TargetDataLine line = null;
    // find a DataLine that can be read
    // (maybe hardcode this if you have multiple microphones)
    Info[] mixerInfo = AudioSystem.getMixerInfo();
    for (int i = 0; i < mixerInfo.length; i++) {
        Mixer mixer = AudioSystem.getMixer(mixerInfo[i]);
        Line.Info[] targetLineInfo = mixer.getTargetLineInfo();
        if (targetLineInfo.length > 0) {
            line = (TargetDataLine) mixer.getLine(targetLineInfo[0]);
            break;
        }
    }
    if (line == null)
        throw new UnsupportedOperationException("No recording device found");
    AudioFormat af = new AudioFormat(11000, 8, 1, true, false);
    line.open(af);
    line.start();
    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    byte[] buf = new byte[(int)af.getSampleRate() * af.getFrameSize()];
    long end = System.currentTimeMillis() + 1000 * duration;
    int len;
    while (System.currentTimeMillis() < end && ((len = line.read(buf, 0, buf.length)) != -1)) {
        baos.write(buf, 0, len);
    }
    line.stop();
    line.close();
    baos.close();

Successivamente, è possibile estrarre i byte dal flusso di output dell'array di byte. Oppure puoi ovviamente elaborarli all'interno del ciclo while se preferisci.

Ecco alcuni codici copiati dal supporto del microfono Sphinx4. Spero che sarà utile.

E un link alla homepage di Sphinx: http://cmusphinx.sourceforge.net/sphinx4/.

/**
 * <p/> A Microphone captures audio data from the system's underlying audio input systems. Converts these audio data
 * into Data objects. When the method <code>startRecording()</code> is called, a new thread will be created and used to
 * capture audio, and will stop when <code>stopRecording()</code> is called. Calling <code>getData()</code> returns the
 * captured audio data as Data objects. </p> <p/> This Microphone will attempt to obtain an audio device with the format
 * specified in the configuration. If such a device with that format cannot be obtained, it will try to obtain a device
 * with an audio format that has a higher sample rate than the configured sample rate, while the other parameters of the
 * format (i.e., sample size, endianness, sign, and channel) remain the same. If, again, no such device can be obtained,
 * it flags an error, and a call <code>startRecording</code> returns false. </p>
 */
public class Microphone extends BaseDataProcessor {

    /**
     * The property for the sample rate of the data.
     */
    @S4Integer(defaultValue = 16000)
    public static final String PROP_SAMPLE_RATE = "sampleRate";

    /**
     * The property that specifies whether or not the microphone will release the audio between utterances.  On
     * certain systems (Linux for one), closing and reopening the audio does not work too well. The default is false for
     * Linux systems, true for others.
     */
    @S4Boolean(defaultValue = true)
    public final static String PROP_CLOSE_BETWEEN_UTTERANCES = "closeBetweenUtterances";

    /**
     * The property that specifies the number of milliseconds of audio data to read each time from the underlying
     * Java Sound audio device.
     */
    @S4Integer(defaultValue = 10)
    public final static String PROP_MSEC_PER_READ = "msecPerRead";

    /**
     * The property for the number of bits per value.
     */
    @S4Integer(defaultValue = 16)
    public static final String PROP_BITS_PER_SAMPLE = "bitsPerSample";

    /**
     * The property specifying the number of channels.
     */
    @S4Integer(defaultValue = 1)
    public static final String PROP_CHANNELS = "channels";

    /**
     * The property specify the endianness of the data.
     */
    @S4Boolean(defaultValue = true)
    public static final String PROP_BIG_ENDIAN = "bigEndian";

    /**
     * The property specify whether the data is signed.
     */
    @S4Boolean(defaultValue = true)
    public static final String PROP_SIGNED = "signed";

    /**
     * The property that specifies whether to keep the audio data of an utterance around until the next utterance
     * is recorded.
     */
    @S4Boolean(defaultValue = false)
    public final static String PROP_KEEP_LAST_AUDIO = "keepLastAudio";

    /**
     * The property that specifies how to convert stereo audio to mono. Currently, the possible values are
     * "average", which averages the samples from at each channel, or "selectChannel", which chooses audio only from
     * that channel. If you choose "selectChannel", you should also specify which channel to use with the
     * "selectChannel" property.
     */
    @S4String(defaultValue = "average", range = {"average", "selectChannel"})
    public final static String PROP_STEREO_TO_MONO = "stereoToMono";

    /**
     * The property that specifies the channel to use if the audio is stereo
     */
    @S4Integer(defaultValue = 0)
    public final static String PROP_SELECT_CHANNEL = "selectChannel";

    /**
     * The property that specifies the mixer to use.  The value can be "default," (which means let the
     * AudioSystem decide), "last," (which means select the last Mixer supported by the AudioSystem), which appears to
     * be what is often used for USB headsets, or an integer value which represents the index of the Mixer.Info that is
     * returned by AudioSystem.getMixerInfo(). To get the list of Mixer.Info objects, run the AudioTool application with
     * a command line argument of "-dumpMixers".
     *
     * @see edu.cmu.sphinx.tools.audio.AudioTool
     */
    @S4String(defaultValue = "default")
    public final static String PROP_SELECT_MIXER = "selectMixer";


    private AudioFormat finalFormat;
    private AudioInputStream audioStream;
    private TargetDataLine audioLine;
    private BlockingQueue<Data> audioList;
    private Utterance currentUtterance;
    private boolean doConversion;
    private final int audioBufferSize = 160000;
    private volatile boolean recording;
    private volatile boolean utteranceEndReached = true;
    private RecordingThread recorder;

    // Configuration data

    private AudioFormat desiredFormat;
    private Logger logger;
    private boolean closeBetweenUtterances;
    private boolean keepDataReference;
    private boolean signed;
    private boolean bigEndian;
    private int frameSizeInBytes;
    private int msecPerRead;
    private int selectedChannel;
    private String selectedMixerIndex;
    private String stereoToMono;
    private int sampleRate;

    /**
     * @param sampleRate sample rate of the data
     * @param bitsPerSample number of bits per value.
     * @param channels number of channels.
     * @param bigEndian the endianness of the data
     * @param signed whether the data is signed.
     * @param closeBetweenUtterances whether or not the microphone will release the audio between utterances.  On
     * certain systems (Linux for one), closing and reopening the audio does not work too well. The default is false for
     * Linux systems, true for others
     * @param msecPerRead the number of milliseconds of audio data to read each time from the underlying
     * Java Sound audio device.
     * @param keepLastAudio whether to keep the audio data of an utterance around until the next utterance
     * is recorded.
     * @param stereoToMono how to convert stereo audio to mono. Currently, the possible values are
     * "average", which averages the samples from at each channel, or "selectChannel", which chooses audio only from
     * that channel. If you choose "selectChannel", you should also specify which channel to use with the
     * "selectChannel" property.
     * @param selectedChannel the channel to use if the audio is stereo
     * @param selectedMixerIndex the mixer to use.  The value can be "default," (which means let the
     * AudioSystem decide), "last," (which means select the last Mixer supported by the AudioSystem), which appears to
     * be what is often used for USB headsets, or an integer value which represents the index of the Mixer.Info that is
     * returned by AudioSystem.getMixerInfo(). To get the list of Mixer.Info objects, run the AudioTool application with
     * a command line argument of "-dumpMixers".
     */
    public Microphone(int sampleRate, int bitsPerSample, int channels,
                      boolean bigEndian, boolean signed, boolean closeBetweenUtterances, int msecPerRead, boolean keepLastAudio,
                      String stereoToMono, int selectedChannel, String selectedMixerIndex) {
        initLogger();

        this.bigEndian = bigEndian;
        this.signed = signed;

        this.desiredFormat = new AudioFormat
                ((float) sampleRate, bitsPerSample, channels, signed, bigEndian);

        this.closeBetweenUtterances = closeBetweenUtterances;
        this.msecPerRead = msecPerRead;
        this.keepDataReference = keepLastAudio;
        this.stereoToMono = stereoToMono;
        this.selectedChannel = selectedChannel;
        this.selectedMixerIndex = selectedMixerIndex;
    }

    public Microphone() {

    }

    /*
    * (non-Javadoc)
    *
    * @see edu.cmu.sphinx.util.props.Configurable#newProperties(edu.cmu.sphinx.util.props.PropertySheet)
    */
    @Override
    public void newProperties(PropertySheet ps) throws PropertyException {
        super.newProperties(ps);
        logger = ps.getLogger();

        sampleRate = ps.getInt(PROP_SAMPLE_RATE);

        int sampleSizeInBits = ps.getInt(PROP_BITS_PER_SAMPLE);

        int channels = ps.getInt(PROP_CHANNELS);
        bigEndian = ps.getBoolean(PROP_BIG_ENDIAN);
        signed = ps.getBoolean(PROP_SIGNED);

        desiredFormat = new AudioFormat
                ((float) sampleRate, sampleSizeInBits, channels, signed, bigEndian);

        closeBetweenUtterances = ps.getBoolean(PROP_CLOSE_BETWEEN_UTTERANCES);
        msecPerRead = ps.getInt(PROP_MSEC_PER_READ);
        keepDataReference = ps.getBoolean(PROP_KEEP_LAST_AUDIO);
        stereoToMono = ps.getString(PROP_STEREO_TO_MONO);
        selectedChannel = ps.getInt(PROP_SELECT_CHANNEL);
        selectedMixerIndex = ps.getString(PROP_SELECT_MIXER);
    }


    /**
     * Constructs a Microphone with the given InputStream.
     */
    @Override
    public void initialize() {
        super.initialize();
        audioList = new LinkedBlockingQueue<Data>();

        DataLine.Info info
                = new DataLine.Info(TargetDataLine.class, desiredFormat);

        /* If we cannot get an audio line that matches the desired
         * characteristics, shoot for one that matches almost
         * everything we want, but has a higher sample rate.
         */
        if (!AudioSystem.isLineSupported(info)) {
            logger.info(desiredFormat + " not supported");
            AudioFormat nativeFormat
                    = DataUtil.getNativeAudioFormat(desiredFormat,
                    getSelectedMixer());
            if (nativeFormat == null) {
                logger.severe("couldn't find suitable target audio format");
            } else {
                finalFormat = nativeFormat;

                /* convert from native to the desired format if supported */
                doConversion = AudioSystem.isConversionSupported
                        (desiredFormat, nativeFormat);

                if (doConversion) {
                    logger.info
                            ("Converting from " + finalFormat.getSampleRate()
                                    + "Hz to " + desiredFormat.getSampleRate() + "Hz");
                } else {
                    logger.info
                            ("Using native format: Cannot convert from " +
                                    finalFormat.getSampleRate() + "Hz to " +
                                    desiredFormat.getSampleRate() + "Hz");
                }
            }
        } else {
            logger.info("Desired format: " + desiredFormat + " supported.");
            finalFormat = desiredFormat;
        }
    }


    /**
     * Gets the Mixer to use.  Depends upon selectedMixerIndex being defined.
     *
     * @see #newProperties
     */
    private Mixer getSelectedMixer() {
        if (selectedMixerIndex.equals("default")) {
            return null;
        } else {
            Mixer.Info[] mixerInfo = AudioSystem.getMixerInfo();
            if (selectedMixerIndex.equals("last")) {
                return AudioSystem.getMixer(mixerInfo[mixerInfo.length - 1]);
            } else {
                int index = Integer.parseInt(selectedMixerIndex);
                return AudioSystem.getMixer(mixerInfo[index]);
            }
        }
    }


    /**
     * Creates the audioLine if necessary and returns it.
     */
    private TargetDataLine getAudioLine() {
        if (audioLine != null) {
            return audioLine;
        }

        /* Obtain and open the line and stream.
        */
        try {
            /* The finalFormat was decided in the initialize() method
             * and is based upon the capabilities of the underlying
             * audio system.  The final format will have all the
             * desired audio characteristics, but may have a sample
             * rate that is higher than desired.  The idea here is
             * that we'll let the processors in the front end (e.g.,
             * the FFT) handle some form of downsampling for us.
             */
            logger.info("Final format: " + finalFormat);

            DataLine.Info info = new DataLine.Info(TargetDataLine.class,
                    finalFormat);

            /* We either get the audio from the AudioSystem (our
             * default choice), or use a specific Mixer if the
             * selectedMixerIndex property has been set.
             */
            Mixer selectedMixer = getSelectedMixer();
            if (selectedMixer == null) {
                audioLine = (TargetDataLine) AudioSystem.getLine(info);
            } else {
                audioLine = (TargetDataLine) selectedMixer.getLine(info);
            }

            /* Add a line listener that just traces
             * the line states.
             */
            audioLine.addLineListener(new LineListener() {
                @Override
                public void update(LineEvent event) {
                    logger.info("line listener " + event);
                }
            });
        } catch (LineUnavailableException e) {
            logger.severe("microphone unavailable " + e.getMessage());
        }

        return audioLine;
    }


    /**
     * Opens the audio capturing device so that it will be ready for capturing audio. Attempts to create a converter if
     * the requested audio format is not directly available.
     *
     * @return true if the audio capturing device is opened successfully; false otherwise
     */
    private boolean open() {
        TargetDataLine audioLine = getAudioLine();
        if (audioLine != null) {
            if (!audioLine.isOpen()) {
                logger.info("open");
                try {
                    audioLine.open(finalFormat, audioBufferSize);
                } catch (LineUnavailableException e) {
                    logger.severe("Can't open microphone " + e.getMessage());
                    return false;
                }

                audioStream = new AudioInputStream(audioLine);
                if (doConversion) {
                    audioStream = AudioSystem.getAudioInputStream
                            (desiredFormat, audioStream);
                    assert (audioStream != null);
                }

                /* Set the frame size depending on the sample rate.
                 */
                float sec = ((float) msecPerRead) / 1000.f;
                frameSizeInBytes =
                        (audioStream.getFormat().getSampleSizeInBits() / 8) *
                                (int) (sec * audioStream.getFormat().getSampleRate());

                logger.info("Frame size: " + frameSizeInBytes + " bytes");
            }
            return true;
        } else {
            logger.severe("Can't find microphone");
            return false;
        }
    }


    /**
     * Returns the format of the audio recorded by this Microphone. Note that this might be different from the
     * configured format.
     *
     * @return the current AudioFormat
     */
    public AudioFormat getAudioFormat() {
        return finalFormat;
    }


    /**
     * Returns the current Utterance.
     *
     * @return the current Utterance
     */
    public Utterance getUtterance() {
        return currentUtterance;
    }


    /**
     * Returns true if this Microphone is recording.
     *
     * @return true if this Microphone is recording, false otherwise
     */
    public boolean isRecording() {
        return recording;
    }


    /**
     * Starts recording audio. This method will return only when a START event is received, meaning that this Microphone
     * has started capturing audio.
     *
     * @return true if the recording started successfully; false otherwise
     */
    public synchronized boolean startRecording() {
        if (recording) {
            return false;
        }
        if (!open()) {
            return false;
        }
        utteranceEndReached = false;
        if (audioLine.isRunning()) {
            logger.severe("Whoops: audio line is running");
        }
        assert (recorder == null);
        recorder = new RecordingThread("Microphone");
        recorder.start();
        recording = true;
        return true;
    }


    /**
     * Stops recording audio. This method does not return until recording has been stopped and all data has been read
     * from the audio line.
     */
    public synchronized void stopRecording() {
        if (audioLine != null) {
            if (recorder != null) {
                recorder.stopRecording();
                recorder = null;
            }
            recording = false;
        }
    }


    /**
     * This Thread records audio, and caches them in an audio buffer.
     */
    class RecordingThread extends Thread {

        private boolean done;
        private volatile boolean started;
        private long totalSamplesRead;
        private final Object lock = new Object();


        /**
         * Creates the thread with the given name
         *
         * @param name the name of the thread
         */
        public RecordingThread(String name) {
            super(name);
        }


        /**
         * Starts the thread, and waits for recorder to be ready
         */
        @Override
        public void start() {
            started = false;
            super.start();
            waitForStart();
        }


        /**
         * Stops the thread. This method does not return until recording has actually stopped, and all the data has been
         * read from the audio line.
         */
        public void stopRecording() {
            audioLine.stop();
            try {
                synchronized (lock) {
                    while (!done) {
                        lock.wait();
                    }
                }
            } catch (InterruptedException e) {
                e.printStackTrace();
            }

            // flush can not be called here because the audio-line might has been set to  null already by the mic-thread 
//          audioLine.flush();
        }


        /**
         * Implements the run() method of the Thread class. Records audio, and cache them in the audio buffer.
         */
        @Override
        public void run() {
            totalSamplesRead = 0;
            logger.info("started recording");

            if (keepDataReference) {
                currentUtterance = new Utterance
                        ("Microphone", audioStream.getFormat());
            }

            audioList.add(new DataStartSignal(sampleRate));
            logger.info("DataStartSignal added");
            try {
                audioLine.start();
                while (!done) {
                    Data data = readData(currentUtterance);
                    if (data == null) {
                        done = true;
                        break;
                    }
                    audioList.add(data);
                }
                audioLine.flush();
                if (closeBetweenUtterances) {
                    /* Closing the audio stream *should* (we think)
                     * also close the audio line, but it doesn't
                     * appear to do this on the Mac.  In addition,
                     * once the audio line is closed, re-opening it
                     * on the Mac causes some issues.  The Java sound
                     * spec is also kind of ambiguous about whether a
                     * closed line can be re-opened.  So...we'll go
                     * for the conservative route and never attempt
                     * to re-open a closed line.
                     */
                    audioStream.close();
                    audioLine.close();
                    System.err.println("set to null");
                    audioLine = null;
                }
            } catch (IOException ioe) {
                logger.warning("IO Exception " + ioe.getMessage());
                ioe.printStackTrace();
            }
            long duration = (long)
                    (((double) totalSamplesRead /
                            (double) audioStream.getFormat().getSampleRate()) * 1000.0);

            audioList.add(new DataEndSignal(duration));
            logger.info("DataEndSignal ended");
            logger.info("stopped recording");

            synchronized (lock) {
                lock.notify();
            }
        }


        /**
         * Waits for the recorder to start
         */
        private synchronized void waitForStart() {
            // note that in theory we coulde use a LineEvent START
            // to tell us when the microphone is ready, but we have
            // found that some javasound implementations do not always
            // issue this event when a line  is opened, so this is a
            // WORKAROUND.

            try {
                while (!started) {
                    wait();
                }
            } catch (InterruptedException ie) {
                logger.warning("wait was interrupted");
            }
        }


        /**
         * Reads one frame of audio data, and adds it to the given Utterance.
         *
         * @param utterance
         * @return an Data object containing the audio data
         * @throws java.io.IOException
         */
        private Data readData(Utterance utterance) throws IOException {

            // Read the next chunk of data from the TargetDataLine.
            byte[] data = new byte[frameSizeInBytes];

            int channels = audioStream.getFormat().getChannels();
            long collectTime = System.currentTimeMillis();
            long firstSampleNumber = totalSamplesRead / channels;

            int numBytesRead = audioStream.read(data, 0, data.length);

            //  notify the waiters upon start
            if (!started) {
                synchronized (this) {
                    started = true;
                    notifyAll();
                }
            }

            if (logger.isLoggable(Level.FINE)) {
                logger.info("Read " + numBytesRead
                        + " bytes from audio stream.");
            }
            if (numBytesRead <= 0) {
                return null;
            }
            int sampleSizeInBytes =
                    audioStream.getFormat().getSampleSizeInBits() / 8;
            totalSamplesRead += (numBytesRead / sampleSizeInBytes);

            if (numBytesRead != frameSizeInBytes) {

                if (numBytesRead % sampleSizeInBytes != 0) {
                    throw new Error("Incomplete sample read.");
                }

                data = Arrays.copyOf(data, numBytesRead);
            }

            if (keepDataReference) {
                utterance.add(data);
            }

            double[] samples;

            if (bigEndian) {
                samples = DataUtil.bytesToValues
                        (data, 0, data.length, sampleSizeInBytes, signed);
            } else {
                samples = DataUtil.littleEndianBytesToValues
                        (data, 0, data.length, sampleSizeInBytes, signed);
            }

            if (channels > 1) {
                samples = convertStereoToMono(samples, channels);
            }

            return (new DoubleData
                    (samples, (int) audioStream.getFormat().getSampleRate(),
                            collectTime, firstSampleNumber));
        }
    }


    /**
     * Converts stereo audio to mono.
     *
     * @param samples  the audio samples, each double in the array is one sample
     * @param channels the number of channels in the stereo audio
     */
    private double[] convertStereoToMono(double[] samples, int channels) {
        assert (samples.length % channels == 0);
        double[] finalSamples = new double[samples.length / channels];
        if (stereoToMono.equals("average")) {
            for (int i = 0, j = 0; i < samples.length; j++) {
                double sum = samples[i++];
                for (int c = 1; c < channels; c++) {
                    sum += samples[i++];
                }
                finalSamples[j] = sum / channels;
            }
        } else if (stereoToMono.equals("selectChannel")) {
            for (int i = selectedChannel, j = 0; i < samples.length;
                 i += channels, j++) {
                finalSamples[j] = samples[i];
            }
        } else {
            throw new Error("Unsupported stereo to mono conversion: " +
                    stereoToMono);
        }
        return finalSamples;
    }


    /**
     * Clears all cached audio data.
     */
    public void clear() {
        audioList.clear();
    }


    /**
     * Reads and returns the next Data object from this Microphone, return null if there is no more audio data. All
     * audio data captured in-between <code>startRecording()</code> and <code>stopRecording()</code> is cached in an
     * Utterance object. Calling this method basically returns the next chunk of audio data cached in this Utterance.
     *
     * @return the next Data or <code>null</code> if none is available
     */
    @Override
    public Data getData() throws DataProcessingException {
        getTimer().start();

        Data output = null;

        if (!utteranceEndReached) {
            try {
                output = audioList.take();
            } catch (InterruptedException ie) {
                throw new DataProcessingException("cannot take Data from audioList", ie);
            }
            if (output instanceof DataEndSignal) {
                utteranceEndReached = true;
            }
        }

        getTimer().stop();

        // signalCheck(output);

        return output;
    }


    /**
     * Returns true if there is more data in the Microphone.
     * This happens either if the a DataEndSignal data was not taken from the buffer,
     * or if the buffer in the Microphone is not yet empty.
     *
     * @return true if there is more data in the Microphone
     */
    public boolean hasMoreData() {
        return !(utteranceEndReached && audioList.isEmpty());
    }
}

Dai un'occhiata a xuggle. Hanno abbandonato il supporto per il progetto, ma ha ancora tutta la documentazione e il google-group a volte ti darà una buona risposta.

Per quanto riguarda specificamente la lettura audio off hardware, iniziare con questi demo e il tuo lavoro da lì.

La parte più difficile di questo è lo streaming dei dati dal tuo microfono, che è abbastanza ben spiegato nell'articolo che hai collegato.

Quindi lo trasmetti in streaming in xuggle utilizzando i documenti oracle, quindi manipolare l'audio come meglio credi.

Non ho provato i seguenti, li ho appena postati solo per aiutarti. si può provare quelli e può aiutare.

Registrare lo streaming audio in java?

Http://docs.blackberry.com/en/developers/deliverables/11942/CS_recording_audio_from_a_player_740038_11.jsp

Http://ganeshtiwaridotcomdotnp.blogspot.com/2011/12/java-sound-capture-from-microphone.html

Http://edenti.deis.unibo.it/utils/Java-tips/Capturing%20Audio%20with%20Java%20Sound%20API.txt

Http://docs.oracle.com/javase/tutorial/sound/capturing.html