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Fork of jpeg2k code from https://code.google.com/p/jj2000/. This is a dependency for support of compression in Grib2 files in netCDF-java and TDS. We welcome bug fixes and other contributions to this code.

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/*****************************************************************************
 *
 * $Id: PaletteBox.java,v 1.1 2002/07/25 14:50:47 grosbois Exp $
 *
 * Copyright Eastman Kodak Company, 343 State Street, Rochester, NY 14650
 * $Date $
 *****************************************************************************/

package colorspace.boxes;

import colorspace .ColorSpaceException;
import icc .ICCProfile;
import jj2000.j2k.util.ParameterList;
import jj2000.j2k.io.RandomAccessIO;

import java.io.IOException;

/**
 * This class models the palette box contained in a JP2
 * image.
 * 
 * @version	1.0
 * @author	Bruce A. Kern
 */
public final class PaletteBox extends JP2Box
{
    static { type = 0x70636c72; }

    private int nentries;
    private int ncolumns;
    private short [] bitdepth;
    private int [][] entries;

    /**
     * Construct a PaletteBox from an input image.
     *   @param in RandomAccessIO jp2 image
     *   @param boxStart offset to the start of the box in the image
     * @exception IOException, ColorSpaceException 
     */
    public PaletteBox (RandomAccessIO in, int boxStart) 
        throws IOException, ColorSpaceException {
        super (in, boxStart);
        readBox(); }

    /** Analyze the box content. */
    void readBox() 
        throws IOException, ColorSpaceException {
        byte [] bfr = new byte [4];
        int i,j,b,m;
        int entry;

        // Read the number of palette entries and columns per entry.
        in.seek((int)dataStart);
        in.readFully (bfr,0,3);
        nentries = ICCProfile.getShort(bfr,0) & 0x0000ffff;
        ncolumns = bfr[2] & 0x0000ffff;

        // Read the bitdepths for each column
        bitdepth = new short [ncolumns];
        bfr = new byte [ncolumns];
        in.readFully (bfr,0,ncolumns);
        for (i=0; i