Example usage for android.media AudioTrack play

Introduction

In this page you can find the example usage for android.media AudioTrack play.

Prototype

public void play() throws IllegalStateException 

Source Link

Document

Starts playing an AudioTrack.

Usage

From source file:net.reichholf.dreamdroid.fragment.SignalFragment.java

void playSound(double freqOfTone) {
    double duration = 0.1; // seconds
    int sampleRate = 8000; // a number

    double dnumSamples = duration * sampleRate;
    dnumSamples = Math.ceil(dnumSamples);
    int numSamples = (int) dnumSamples;
    double sample[] = new double[numSamples];
    byte generatedSnd[] = new byte[2 * numSamples];

    for (int i = 0; i < numSamples; ++i) { // Fill the sample array
        sample[i] = Math.sin(freqOfTone * 2 * Math.PI * i / (sampleRate));
    }/*from   w ww  . j  a  v a 2  s  . c  o m*/

    // convert to 16 bit pcm sound array
    // assumes the sample buffer is normalized.
    int idx = 0;
    int i = 0;

    int ramp = numSamples / 20; // Amplitude ramp as a percent of sample
    // count

    for (i = 0; i < numSamples; ++i) { // Ramp amplitude up (to avoid
        // clicks)
        if (i < ramp) {
            double dVal = sample[i];
            // Ramp up to maximum
            final short val = (short) ((dVal * 32767 * i / ramp));
            // in 16 bit wav PCM, first byte is the low order byte
            generatedSnd[idx++] = (byte) (val & 0x00ff);
            generatedSnd[idx++] = (byte) ((val & 0xff00) >>> 8);
        } else if (i < numSamples - ramp) {
            // Max amplitude for most of the samples
            double dVal = sample[i];
            // scale to maximum amplitude
            final short val = (short) ((dVal * 32767));
            // in 16 bit wav PCM, first byte is the low order byte
            generatedSnd[idx++] = (byte) (val & 0x00ff);
            generatedSnd[idx++] = (byte) ((val & 0xff00) >>> 8);
        } else {
            double dVal = sample[i];
            // Ramp down to zero
            final short val = (short) ((dVal * 32767 * (numSamples - i) / ramp));
            // in 16 bit wav PCM, first byte is the low order byte
            generatedSnd[idx++] = (byte) (val & 0x00ff);
            generatedSnd[idx++] = (byte) ((val & 0xff00) >>> 8);
        }
    }

    AudioTrack audioTrack = null; // Get audio track
    try {
        audioTrack = new AudioTrack(AudioManager.STREAM_MUSIC, sampleRate, AudioFormat.CHANNEL_OUT_MONO,
                AudioFormat.ENCODING_PCM_16BIT, (int) numSamples * 2, AudioTrack.MODE_STATIC);
        // Load the track
        audioTrack.write(generatedSnd, 0, generatedSnd.length);
        audioTrack.play(); // Play the track
    } catch (Exception e) {
    }

    int x = 0;
    do { // Montior playback to find when done
        if (audioTrack != null)
            x = audioTrack.getPlaybackHeadPosition();
        else
            x = numSamples;
    } while (x < numSamples);

    if (audioTrack != null)
        audioTrack.release(); // Track play done. Release track.
}

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From source file:zlyh.dmitry.recaller.threading.PlayBlockThread.java

@Override
public void run() {
    AudioTrack audioTrack = null;
    FileInputStream in = null;/*  w  w  w  . ja v  a2 s  . com*/

    try {
        File rawpcm = new File(path);
        if (!rawpcm.exists()) {
            this.interrupt();
        }

        togglePlaying(true);

        final int audioLength = (int) rawpcm.length();
        final int minBufferSize = AudioRecord.getMinBufferSize(RecordRunnable.frequency,
                AudioFormat.CHANNEL_IN_MONO, AudioFormat.ENCODING_PCM_16BIT);
        audioTrack = new AudioTrack(AudioManager.STREAM_MUSIC, RecordRunnable.frequency,
                AudioFormat.CHANNEL_OUT_MONO, AudioFormat.ENCODING_PCM_16BIT, minBufferSize,
                AudioTrack.MODE_STREAM);

        final int block = 256 * 1024;
        byte[] byteData = new byte[block];

        try {
            in = new FileInputStream(rawpcm);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
            this.interrupt();
        }

        if (in != null) {
            try {
                int bytesread = 0;
                int offset;
                audioTrack.play();
                while (bytesread < audioLength && !isInterrupted()) {
                    offset = in.read(byteData, 0, block);
                    if (offset != -1) {
                        audioTrack.write(byteData, 0, offset);
                        bytesread += offset;
                    } else {
                        break;
                    }
                }
                in.close();

                togglePlaying(false);

                if (audioTrack.getState() == AudioTrack.PLAYSTATE_PLAYING) {
                    audioTrack.stop();
                }

                if (audioTrack.getState() == AudioTrack.STATE_INITIALIZED) {
                    audioTrack.release();
                }
            } catch (Exception e) {
                e.printStackTrace();
                try {
                    in.close();
                } catch (IOException e1) {
                    e1.printStackTrace();
                }

                if (audioTrack.getState() == AudioTrack.PLAYSTATE_PLAYING) {
                    audioTrack.stop();
                }
                if (audioTrack.getState() == AudioTrack.STATE_INITIALIZED) {
                    audioTrack.release();
                }
                togglePlaying(false);

            }
        }
    } catch (Exception e) {
        e.printStackTrace();
        if (audioTrack != null) {
            if (audioTrack.getState() == AudioTrack.PLAYSTATE_PLAYING) {
                audioTrack.stop();
            }
            if (audioTrack.getState() == AudioTrack.STATE_INITIALIZED) {
                audioTrack.release();
            }
        }

        if (in != null) {
            try {
                in.close();
            } catch (IOException e1) {
                e1.printStackTrace();
            }
        }
        togglePlaying(false);

    }

}

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