byteio.h

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/* ***** BEGIN LICENSE BLOCK *****
*
* $Id: byteio.h,v 1.11 2009/01/21 05:18:09 asuraparaju Exp $ $Name: Dirac_1_0_2 $
*
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
* the specific language governing rights and limitations under the License.
*
* The Original Code is BBC Research and Development code.
*
* The Initial Developer of the Original Code is the British Broadcasting
* Corporation.
* Portions created by the Initial Developer are Copyright (C) 2004.
* All Rights Reserved.
*
* Contributor(s): Andrew Kennedy (Original Author),
*                 Anuradha Suraparaju
*
* Alternatively, the contents of this file may be used under the terms of
* the GNU General Public License Version 2 (the "GPL"), or the GNU Lesser
* Public License Version 2.1 (the "LGPL"), in which case the provisions of
* the GPL or the LGPL are applicable instead of those above. If you wish to
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* your version of this file under the terms of any one of the MPL, the GPL
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* ***** END LICENSE BLOCK ***** */
 
#ifndef byteio_h
#define byteio_h
 
// SYSTEM INCLUDES
#include <iostream>             // IO classes
#include <sstream>              // IO classes
#include <iomanip>              // setw
#include <climits>              // CHAR_BIT
 
//LOCAL INCLUDEs
#include <libdirac_byteio/dirac_byte_stats.h>   // stores stats
 
namespace dirac
{
    
    // BIT DEFS
    #define BIT_ZERO 0
    #define BIT_ONE 1
 
    // most significant bit in a character 
    #define MS_BIT                (1 << (CHAR_BIT - 1))
 
    /* array index for character containing bit */
    //#define BIT_IN_CHAR(bit)      (1 << (CHAR_BIT-1-bit))
    #define BIT_IN_CHAR(bit)      (1 << bit)
 
 
   class ByteIO
   {
   public:
       
       ByteIO(bool new_stream=true);
 
       ByteIO(const ByteIO& stream_data);
 
       virtual ~ByteIO();
 
       virtual void CollateByteStats(DiracByteStats& dirac_byte_stats) 
       { dirac_byte_stats.Clear(); }
 
        virtual const std::string GetBytes();
 
        int GetReadBytePosition() const { return mp_stream->tellg();};
 
 
        virtual int GetSize() const;
 
        void SetByteParams(const ByteIO& byte_io);
 
        void ByteAlignOutput();
 
        //void OutputVarLengthUint(const unsigned int& value);
        void WriteUint(unsigned int value);
 
         void SetBitsLeft(int left_bits) { m_bits_left = left_bits; }
 
         int BitsLeft(void) { return m_bits_left; }
 
    protected:
 
        inline bool CanRead() const { return(!mp_stream->eof()); }
 
        inline bool GetBit(unsigned char& c, int pos) const { return (c & BIT_IN_CHAR(pos)); }
 
        inline void SetBit(unsigned char& c, int pos) const { c |= BIT_IN_CHAR(pos); }
 
        inline void SetBits(unsigned char& c, unsigned char bits) const { c |= bits; }
 
        void ByteAlignInput();
 
 
        bool ReadBool();
 
        bool ReadBoolB();
 
        int ReadBit();
 
        int ReadBitB();
 
        unsigned int ReadNBits(int count);
 
        void InputBytes(char* data, int count)
        {
            //int j=mp_stream->tellg();
            mp_stream->read(data, count);
 
            //int h=mp_stream->tellg();
        }
 
        void FlushInputB();
 
        //int InputVarLengthInt();
        int ReadSint();
 
        int ReadSintB();
 
        //unsigned int InputVarLengthUint();
        unsigned int ReadUint();
 
        //unsigned int InputVarLengthUint();
        unsigned int ReadUintB();
 
        //inline unsigned int InputFixedLengthUint(const int byte_size) { 
        inline unsigned int ReadUintLit(const int byte_size) { 
           unsigned int val=0; 
           for(int i=0; i < byte_size; ++i)
           {
               val <<= 8;
               val += (unsigned char)mp_stream->get();
           }
           m_num_bytes+=byte_size;
           return val;
        } 
 
        inline unsigned char InputUnByte() {m_num_bytes++ ; return mp_stream->get(); }
 
        inline std::string InputUnString(const int count) 
        {
            std::string str;
            for(int index=0; index < count; ++index)
                str.push_back(InputUnByte());
            return str;
        }
 
        void WriteBit(const bool& bit);
 
        int WriteNBits(unsigned int val);
 
        void WriteNBits(unsigned int val, int count);
 
 
 
        void OutputBytes(const std::string& bytes) {
           int cur_pos = mp_stream->tellg();
          mp_stream->str(mp_stream->str()+bytes);
           m_num_bytes+=bytes.size();
        //   *mp_stream << bytes;
           mp_stream->seekg(std::max(cur_pos,0), std::ios_base::beg);
        }
 
        inline void OutputCurrentByte()
        {
            if (m_current_pos)
            {
                *mp_stream << (m_current_byte);
                ++m_num_bytes;
                m_current_pos = 0;
                m_current_byte = 0;
            }
        };
 
       //void OutputVarLengthInt(const int val);
       void WriteSint(int val);
 
       //inline void OutputFixedLengthUint(const unsigned int& value, const int& length)
       inline void WriteUintLit(const unsigned int& value, const int& length)
       {
           for(int i=length-1; i >=0 ; --i)
           {
              unsigned char cp = (value>>(i*8))&0xff; 
               *mp_stream << cp;
           }
           m_num_bytes+=length;
       }
       
       void RemoveRedundantBytes(const int count);
 
       inline void SeekGet(const int offset, std::ios_base::seekdir dir) 
       {
           mp_stream->seekg(offset, dir);
       }
 
       std::stringstream*    mp_stream;
 
 
   private:
       
       friend class ArithCodecBase;
 
       friend class ArithCodecToVLCAdapter;
 
       unsigned char m_current_byte;
            
       int m_current_pos;
 
       int m_num_bytes;
       
       bool m_new_stream;
        
       int m_bits_left;
   protected:
 
        
   };
 
 
 
} // namespace dirac
 
#endif