org.jpedal.jbig2.segment.pageinformation.PageInformationSegment Maven / Gradle / Ivy

/**
 * ===========================================
 * Java Pdf Extraction Decoding Access Library
 * ===========================================
 * 
 * Project Info:  http://www.jpedal.org
 * (C) Copyright 1997-2008, IDRsolutions and Contributors.
 * Main Developer: Simon Barnett
 * 

 * This file is part of JPedal
 * 

 * Copyright (c) 2008, IDRsolutions
 * All rights reserved.
 * 

 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 * * Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 * * Neither the name of the IDRsolutions nor the
 * names of its contributors may be used to endorse or promote products
 * derived from this software without specific prior written permission.
 * 

 * THIS SOFTWARE IS PROVIDED BY IDRsolutions ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL IDRsolutions BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 

 * Other JBIG2 image decoding implementations include
 * jbig2dec (http://jbig2dec.sourceforge.net/)
 * xpdf (http://www.foolabs.com/xpdf/)
 * 

 * The final draft JBIG2 specification can be found at http://www.jpeg.org/public/fcd14492.pdf
 * 

 * All three of the above resources were used in the writing of this software, with methodologies,
 * processes and inspiration taken from all three.
 * 
 * ---------------
 * PageInformationSegment.java
 * ---------------
 */
package org.jpedal.jbig2.segment.pageinformation;

import org.jpedal.jbig2.JBIG2Exception;
import org.jpedal.jbig2.decoders.JBIG2StreamDecoder;
import org.jpedal.jbig2.image.JBIG2Bitmap;
import org.jpedal.jbig2.segment.Segment;
import org.jpedal.jbig2.util.BinaryOperation;

import java.io.IOException;

public class PageInformationSegment extends Segment {

    private int pageBitmapHeight, pageBitmapWidth;
    private int yResolution, xResolution;

    PageInformationFlags pageInformationFlags = new PageInformationFlags();
    private int pageStriping;

    private JBIG2Bitmap pageBitmap;

    public PageInformationSegment(JBIG2StreamDecoder streamDecoder) {
        super(streamDecoder);
    }

    public PageInformationFlags getPageInformationFlags() {
        return pageInformationFlags;
    }

    public JBIG2Bitmap getPageBitmap() {
        return pageBitmap;
    }

    public void readSegment() throws IOException, JBIG2Exception {

        if (JBIG2StreamDecoder.debug)
            System.out.println("==== Reading Page Information Dictionary ====");

        short[] buff = new short[4];
        decoder.readByte(buff);
        pageBitmapWidth = BinaryOperation.getInt32(buff);

        buff = new short[4];
        decoder.readByte(buff);
        pageBitmapHeight = BinaryOperation.getInt32(buff);

        if (JBIG2StreamDecoder.debug)
            System.out.println("Bitmap size = " + pageBitmapWidth + 'x' + pageBitmapHeight);

        buff = new short[4];
        decoder.readByte(buff);
        xResolution = BinaryOperation.getInt32(buff);

        buff = new short[4];
        decoder.readByte(buff);
        yResolution = BinaryOperation.getInt32(buff);

        if (JBIG2StreamDecoder.debug)
            System.out.println("Resolution = " + xResolution + 'x' + yResolution);

        /** extract page information flags */
        short pageInformationFlagsField = decoder.readByte();

        pageInformationFlags.setFlags(pageInformationFlagsField);

        if (JBIG2StreamDecoder.debug)
            System.out.println("symbolDictionaryFlags = " + pageInformationFlagsField);

        buff = new short[2];
        decoder.readByte(buff);
        pageStriping = BinaryOperation.getInt16(buff);

        if (JBIG2StreamDecoder.debug)
            System.out.println("Page Striping = " + pageStriping);

        int defPix = pageInformationFlags.getFlagValue(PageInformationFlags.DEFAULT_PIXEL_VALUE);

        int height;

        if (pageBitmapHeight == -1) {
            height = pageStriping & 0x7fff;
        } else {
            height = pageBitmapHeight;
        }

        pageBitmap = new JBIG2Bitmap(pageBitmapWidth, height, arithmeticDecoder, huffmanDecoder, mmrDecoder);
        pageBitmap.clear(defPix);
    }

    public int getPageBitmapHeight() {
        return pageBitmapHeight;
    }
}