rawwriter.java

It is the Speech recognition software. It is platform independent. To execute the source code,

/*
 * Copyright 1999-2004 Carnegie Mellon University.  
 * Portions Copyright 2002-2004 Sun Microsystems, Inc.  
 * Portions Copyright 2002-2004 Mitsubishi Electric Research Laboratories.
 * All Rights Reserved.  Use is subject to license terms.
 * 
 * See the file "license.terms" for information on usage and
 * redistribution of this file, and for a DISCLAIMER OF ALL 
 * WARRANTIES.
 *
 */

package edu.cmu.sphinx.tools.audio;

import java.io.IOException;
import java.io.OutputStream;

import javax.sound.sampled.AudioFormat;


/**
 * Writes raw audio to a file, handling sample size, endian format,
 * and signed/unsigned data.
 */
public class RawWriter {
    private OutputStream outputStream;
    private int bytesPerSample;
    private boolean signedData;
    private boolean bigEndian;

    /**
     */
    public RawWriter(OutputStream outputStream,
                     AudioFormat audioFormat) {
        AudioFormat.Encoding encoding = audioFormat.getEncoding();        
        this.outputStream = outputStream;
        this.bytesPerSample = audioFormat.getSampleSizeInBits() / 8;
        if (encoding == AudioFormat.Encoding.PCM_SIGNED) {
            this.signedData = true;
        } else if (encoding == AudioFormat.Encoding.PCM_UNSIGNED) {
            this.signedData = false;
        } else {
            System.err.println("Unsupported audio encoding: " + encoding);
            System.exit(-1);
        }
        this.bigEndian = audioFormat.isBigEndian();
    }

    /**
     * Writes the sample to the output stream.
     *
     * @throws java.io.IOException
     */
    public void writeSample(int sample) throws IOException {
        /* First byte contains the big endian byte that carries the sign.
         */
        if (signedData) {
            outputStream.write(sample >> ((bytesPerSample - 1) * 8)); 
        } else {
            outputStream.write((sample >> ((bytesPerSample - 1) * 8)) & 0xff);
        }

        /* Now just output the rest of the data in big endian form.
         */
        for (int i = bytesPerSample - 2; i >= 0; i--) {
            outputStream.write((sample >> (i * 8)) & 0xff);
        }
    }
}