content: // ===============================================================================
  // Authors: AFRL/RQQD
  // Organization: Air Force Research Laboratory, Aerospace Systems Directorate, Power and Control Division
  // 
  // Copyright (c) 2017 Government of the United State of America, as represented by
  // the Secretary of the Air Force.  No copyright is claimed in the United States under
  // Title 17, U.S. Code.  All Other Rights Reserved.
  // ===============================================================================
  
  /*
   * GRAL: GRAphing Library for Java(R)
   *
   * (C) Copyright 2009-2013 Erich Seifert <dev[at]erichseifert.de>,
   * Michael Seifert <mseifert[at]error-reports.org>
   *
   * This file is part of GRAL.
   *
   * GRAL is free software: you can redistribute it and/or modify
   * it under the terms of the GNU Lesser General Public License as published by
   * the Free Software Foundation, either version 3 of the License, or
   * (at your option) any later version.
   *
   * GRAL is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public License
   * along with GRAL.  If not, see <http://www.gnu.org/licenses/>.
   */
  package de.erichseifert.gral.io.data;
  
  import java.io.IOException;
  import java.io.InputStream;
  
  import javax.sound.sampled.AudioInputStream;
  import javax.sound.sampled.AudioSystem;
  import javax.sound.sampled.UnsupportedAudioFileException;
  
  import de.erichseifert.gral.data.DataSource;
  import de.erichseifert.gral.data.DataTable;
  import de.erichseifert.gral.io.IOCapabilities;
  import de.erichseifert.gral.util.Messages;
  
  
  /**
   * Class that reads a data source from a binary image file. This class
   * shouldn't be used directly but using the {@link DataReaderFactory}.
   */
  public class AudioReader extends AbstractDataReader {
  	static {
  		addCapabilities(new IOCapabilities(
  			"WAV", //$NON-NLS-1$
  			Messages.getString("DataIO.wavDescription"), //$NON-NLS-1$
  			"audio/wav", //$NON-NLS-1$
  			new String[] {"wav"} //$NON-NLS-1$
  		));
  	}
  
  	/**
  	 * Creates a new instance with the specified MIME type.
  	 * @param mimeType MIME type of the file format to be read.
  	 */
  	public AudioReader(String mimeType) {
  		super(mimeType);
  		setDefault("factor", 1.0); //$NON-NLS-1$
  		setDefault("offset", 0.0); //$NON-NLS-1$
  	}
  
  	/**
  	 * Returns a data source that was imported.
  	 * @param input Input to be read.
  	 * @param types Number types for the columns of the data source.
  	 * @return DataSource Imported data.
  	 * @throws IOException when the file format is not valid or when
  	 *         experiencing an error during file operations.
  	 */
  	@SuppressWarnings("unchecked")
  	public DataSource read(InputStream input, Class<? extends Comparable<?>>... types)
  			throws IOException {
  		AudioInputStream audio;
  		try {
  			audio = AudioSystem.getAudioInputStream(input);
  		} catch (UnsupportedAudioFileException e) {
  			throw new IOException(e);
  		}
  
  		// FIXME Should the types parameter be used?
  		DataTable data = new DataTable(Double.class);
  
  		double factor = this.<Number>getSetting("factor") //$NON-NLS-1$
  			.doubleValue();
  		double offset = this.<Number>getSetting("offset") //$NON-NLS-1$
  			.doubleValue();
  
  		int sampleSize = audio.getFormat().getSampleSizeInBits();
  		byte[] samples = new byte[sampleSize/8];
  
  		// see: http://www.jsresources.org/faq_audio.html#reconstruct_samples
  		while (audio.read(samples) >= 0) {
  			int b = samples[0];
  			if (samples.length == 1) {
  				b = b << 8;
  			} else if (samples.length == 2) {
  				b = (b & 0xFF) | (samples[1] << 8);
  			}
  			double v = factor*b + offset;
  			data.add(v);
  		}
  
  		return data;
  	}
  
  }
  