energyplotter.java

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

/*
 * Copyright 1999-2002 Carnegie Mellon University.  
 * Portions Copyright 2002 Sun Microsystems, Inc.  
 * Portions Copyright 2002 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.frontend.util;

import java.util.Arrays;

import edu.cmu.sphinx.frontend.Data;
import edu.cmu.sphinx.frontend.DoubleData;
import edu.cmu.sphinx.util.SphinxProperties;


/**
 * Plots positive energy values of a cepstrum to stdout.
 * The energy value is assumed to be the first element of the 
 * double array returned by <code>Data.getValues()</code>. 
 * For negative energy value, a "-" will be printed out.
 * The plots look like the following, one line per cepstrum. The
 * energy value for that particular cepstrum is printed at the end of
 * the line.
 * <p>
 * <code>
<br>+......7
<br>+......7
<br>Cepstrum: SPEECH_START
<br>+......7
<br>+.......8
<br>+......7
<br>+.......8
<br>+.......8
<br>+........9
<br>+............14
<br>+...........13
<br>+...........13
<br>+...........13
<br>+.............15
<br>+.............15
<br>+..............16
<br>+..............16
<br>+..............16
<br>+.............15
<br>+............14
<br>+............14
<br>+............14
<br>+............14
<br>+.............15
<br>+..............16
<br>+...............17
<br>+...............17
<br>+...............17
<br>+...............17
<br>+...............17
<br>+...............17
<br>+..............16
<br>+.............15
<br>+............14
<br>+............14
<br>+............14
<br>+...........13
<br>+........9
<br>+.......8
<br>+......7
<br>+......7
<br>+......7
<br>Cepstrum: SPEECH_END
<br>+......7
</code>
 */
public class EnergyPlotter {

    /**
     * The maximum level of energy for which a plot string will be
     * preconstructed.
     */
    public static final String PROP_MAX_ENERGY =
        "edu.cmu.sphinx.frontend.util.EnergyPlotter.maxEnergy";

    /**
     * The default value of PROP_MAX_ENERGY.
     */
    public static final int PROP_MAX_ENERGY_DEFAULT = 20;


    private int maxEnergy;
    private String[] plots;


    /**
     * Constructs an EnergyPlotter.
     *
     * @param props the SphinxProperties for this object.
     */
    public EnergyPlotter(SphinxProperties props) {
        maxEnergy = props.getInt(PROP_MAX_ENERGY, PROP_MAX_ENERGY_DEFAULT);
        buildPlots(maxEnergy);
    }


    /**
     * Builds the strings for the plots.
     *
     * @param maxEnergy the maximum energy value
     */
    private void buildPlots(int maxEnergy) {
        plots = new String[maxEnergy+1];
        for (int i = 0; i < maxEnergy+1; i++) {
            plots[i] = getPlotString(i);
        }
    }


    /**
     * Returns the plot string for the given energy.
     *
     * @param energy the energy level
     */
    private String getPlotString(int energy) {
        char[] plot = new char[energy];
        Arrays.fill(plot, '.');
        if (energy > 0) {
            if (energy < 10) {
                plot[plot.length - 1] = (char) ('0' + energy);
            } else {
                plot[plot.length - 2] = '1';
                plot[plot.length - 1] = (char) ('0' + (energy - 10));
            }
        }
        return ("+" + new String(plot));
    }

    
    /**
     * Plots the energy values of the given Data to System.out.
     * If the Data contains a signal, it prints the signal.
     *
     * @param cepstrum the Data to plot
     */
    public void plot(Data cepstrum) {
        if (cepstrum != null) {
            if (cepstrum instanceof DoubleData) {
                int energy = (int) ((DoubleData) cepstrum).getValues()[0];
                System.out.println(getPlot(energy));
            } else {
                System.out.println(cepstrum.toString());
            }
        }
    }


    /**
     * Returns the corresponding plot String for the given energy value.
     * The energy value should be positive or zero. If its negative,
     * It will output the string "-".
     *
     * @return energy the energy value
     */
    private String getPlot(int energy) {
        if (energy < 0) {
            return "-";
        } else if (energy <= maxEnergy) {
            return plots[energy];
        } else {
            return getPlotString(energy);
        }
    }
}