!7

p-exp {

  assertOnPATH("aplay");

  Process process = Runtime.getRuntime().exec("aplay");

  InputStream in = process.getInputStream();

  drainStreamInNewThread(in); // just to take care of it

  OutputStream out = process.getOutputStream();

  int sampleRate = 44100;    // Samples per second

  double duration = 5.0;     // Seconds

  // Calculate the number of frames required for specified duration

  long numFrames = (long)(duration * sampleRate);

  // Create a wav file with the name specified as the first argument

  GSWavFile wavFile = GSWavFile.newWavFile(out, null, 2, numFrames, 16, sampleRate);

  // Create a buffer of 100 frames

  double[][] buffer = new double[2][100];

  long frameCounter = 0;

  while (frameCounter < numFrames) {

    // Determine how many frames to write, up to a maximum of the buffer size

    long remaining = wavFile.getFramesRemaining();

    int toWrite = (remaining > 100) ? 100 : (int) remaining;

    // Fill the buffer, one tone per channel

    for (int s=0 ; s<toWrite ; s++, frameCounter++)

    {

       buffer[0][s] = Math.sin(2.0 * Math.PI * 400 * frameCounter / sampleRate);

       buffer[1][s] = Math.sin(2.0 * Math.PI * 500 * frameCounter / sampleRate);

    }

    // Write the buffer

    wavFile.writeFrames(buffer, toWrite);

  }

  // Close the wavFile

  wavFile.close();

}