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/*
 * ===========================================
 * Java Pdf Extraction Decoding Access Library
 * ===========================================
 *
 * Project Info:  http://www.idrsolutions.com
 * Help section for developers at http://www.idrsolutions.com/support/
 *
 * (C) Copyright 1997-2015 IDRsolutions and Contributors.
 *
 * This file is part of JPedal/JPDF2HTML5
 *
     This library 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 2.1 of the License, or (at your option) any later version.

    This library 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 this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA


 *
 * ---------------
 * CCITT.java
 * ---------------
 */
package org.jpedal.io.filter;

import org.jpedal.io.filter.ccitt.CCITT2D;
import org.jpedal.io.filter.ccitt.CCITTMix;
import org.jpedal.objects.raw.PdfDictionary;
import org.jpedal.objects.raw.PdfObject;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.util.Map;

/**
 * CCITT
 */
public class CCITT extends BaseFilter implements PdfFilter {

    private final int width;
    private final int height;


    public CCITT(final PdfObject decodeParms, final int width, final int height) {

        super(decodeParms);

        this.width=width;
        this.height=height;

    }

    @Override
    public byte[] decode(final byte[] data) throws Exception {

        // flag set to ensure that only new code gets execued
        return decodeCCITT(data);

    }

    @Override
    public void decode(final BufferedInputStream bis, final BufferedOutputStream streamCache, final String cacheName, final Map cachedObjects) throws Exception {

        final int size = bis.available();
        byte[] data = new byte[size];
        bis.read(data);
        data = decodeCCITT(data);


        streamCache.write(data);
    }

    private byte[] decodeCCITT(final byte[] rawData) throws Exception {

        final byte[] data;

        int K= 0;
        if(decodeParms!=null){
            K = decodeParms.getInt(PdfDictionary.K);
        }
        
        //new CCITT decoder - encodes runs of black or white pixels
        //always assumes white to start
        org.jpedal.io.filter.ccitt.CCITTDecoder ccitt=null;

        if(K==0){

            //Pure 1D decoding, group3
            ccitt = new org.jpedal.io.filter.ccitt.CCITT1D(rawData, width, height, decodeParms);

            //K<0 case
            //Pure 2D, group 4
        }else if (K<0){

            ccitt= new CCITT2D(rawData, width, height, decodeParms);

        }else if (K>0){
            //Mixed 1/2 D encoding we can use either for maximum compression
            // A 1D line can be followed by up to K-1 2D lines

            ccitt= new CCITTMix(rawData, width, height, decodeParms);
        }

        data = ccitt.decode();

        return data;
    }


}