LZWDecode.h

/*
 * Copyright (C) 2015-2018 Département de l'Instruction Publique (DIP-SEM)
 *
 * Copyright (C) 2013 Open Education Foundation
 *
 * Copyright (C) 2010-2013 Groupement d'Intérêt Public pour
 * l'Education Numérique en Afrique (GIP ENA)
 *
 * This file is part of OpenBoard.
 *
 * OpenBoard is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, version 3 of the License,
 * with a specific linking exception for the OpenSSL project's
 * "OpenSSL" library (or with modified versions of it that use the
 * same license as the "OpenSSL" library).
 *
 * OpenBoard 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with OpenBoard. If not, see <http://www.gnu.org/licenses/>.
 */




#ifndef LZWDecode_H
#define LZWDecode_H

#include <string>
#include "Decoder.h"
#include "FilterPredictor.h"

namespace merge_lib
{
   // this class provides method for FlateDecode encoding and decoding
   class LZWDecode : public Decoder
   {
   public:
      LZWDecode();
      virtual ~LZWDecode();
      bool encode(std::string & decoded);
      bool decode(std::string & encoded);
      void initialize(Object * objectWithStram);
   private:

      FilterPredictor *_predict;

      void clearTable();
      int getCode();

      std::string _dummy;
      std::string &_encoded;
      size_t _curSymbolIndex;

      int _earlyChange;    // early parameter
      int _readBuf;       
      int _readBits;       
      int _nextCode;     
      int _bitsToRead;     
      bool _first;          
      int _curSequenceLength;    
   };
}

#endif // LZW_DECODE_H_INCLUDED