/* ***** BEGIN LICENSE BLOCK ***** * Source last modified: $Id: lzw.h,v 1.1.26.1 2004/07/09 01:54:26 hubbe Exp $ *  * Portions Copyright (c) 1995-2004 RealNetworks, Inc. All Rights Reserved. *  * The contents of this file, and the files included with this file, * are subject to the current version of the RealNetworks Public * Source License (the "RPSL") available at * http://www.helixcommunity.org/content/rpsl unless you have licensed * the file under the current version of the RealNetworks Community * Source License (the "RCSL") available at * http://www.helixcommunity.org/content/rcsl, in which case the RCSL * will apply. You may also obtain the license terms directly from * RealNetworks.  You may not use this file except in compliance with * the RPSL or, if you have a valid RCSL with RealNetworks applicable * to this file, the RCSL.  Please see the applicable RPSL or RCSL for * the rights, obligations and limitations governing use of the * contents of the file. *  * Alternatively, the contents of this file may be used under the * terms of the GNU General Public License Version 2 or later (the * "GPL") in which case the provisions of the GPL are applicable * instead of those above. If you wish to allow use of your version of * this file only under the terms of the GPL, and not to allow others * to use your version of this file under the terms of either the RPSL * or RCSL, indicate your decision by deleting the provisions above * and replace them with the notice and other provisions required by * the GPL. If you do not delete the provisions above, a recipient may * use your version of this file under the terms of any one of the * RPSL, the RCSL or the GPL. *  * This file is part of the Helix DNA Technology. RealNetworks is the * developer of the Original Code and owns the copyrights in the * portions it created. *  * This file, and the files included with this file, is distributed * and made available on an 'AS IS' basis, WITHOUT WARRANTY OF ANY * KIND, EITHER EXPRESS OR IMPLIED, AND REALNETWORKS HEREBY DISCLAIMS * ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET * ENJOYMENT OR NON-INFRINGEMENT. *  * Technology Compatibility Kit Test Suite(s) Location: *    http://www.helixcommunity.org/content/tck *  * Contributor(s): *  * ***** END LICENSE BLOCK ***** */#ifndef _LZW_CODEC_H#define _LZW_CODEC_H#include "hxtypes.h"#include "hxresult.h"class LZWCodec{protected:    enum    {        kMaxLZWBits = 12,        kMaxLZWVal  = 4096    };    /* Decompression member variables */    BOOL   m_bFresh;    BOOL   m_bPostClearCode;    INT32  m_lCodeSize;    INT32  m_lSetCodeSize;    INT32  m_lMaxCode;    INT32  m_lMaxCodeSize;    INT32  m_lFirstCode;    INT32  m_lOldCode;    INT32  m_lClearCode;    INT32  m_lEndCode;    INT32  m_lTable[2][kMaxLZWVal];    INT32  m_lStack[kMaxLZWVal << 1];    INT32 *m_plStackPtr;    /* Decompression input buffer variables */    BYTE  *m_pCompressedBuffer;    INT32  m_lCompressedBufferSize;    INT32  m_lCompressedBytesCopied;    BYTE  *m_pCurByte;    INT32  m_lCurBit;    INT32  m_lBytesInBuffer;    BOOL   m_bFinished;    BOOL   m_bSuspended;    BOOL   m_bAllCompressedDataCopied;    inline void ClearTables()    {        INT32 i;        for (i = 0; i < m_lClearCode; i++)        {            m_lTable[0][i] = 0;            m_lTable[1][i] = i;        }        for (; i < kMaxLZWVal; i++)        {            m_lTable[0][i] = m_lTable[1][i] = 0;        }    };    inline INT32 GetCode()    {        /* Make copy of state variables in case we run out of data */        BYTE  *pCurByte       = m_pCurByte;        INT32  lCurBit        = m_lCurBit;        INT32  lBytesInBuffer = m_lBytesInBuffer;        // Check to make sure we have some data        if (lBytesInBuffer < 0)        {            return -1;        }        INT32 lCode = 0;        for (INT32 i = 0; i < m_lCodeSize; i++)        {            /* Copy the current bit */            if (*pCurByte & (1 << lCurBit))            {                lCode |= 1 << i;            }            /* Increment the bit counter */            lCurBit++;            /* Update the buffer variables as necessary */            if (lCurBit == 8)            {                if (lBytesInBuffer == 0 && i < m_lCodeSize - 1)                {                    return -1;                }                pCurByte++;                lCurBit = 0;                lBytesInBuffer--;            }        }        /* We were successful, so update the state variables */        m_pCurByte       = pCurByte;        m_lCurBit        = lCurBit;        m_lBytesInBuffer = lBytesInBuffer;        return lCode;    };public:    LZWCodec();    ~LZWCodec();    inline BOOL Finished()  { return m_bFinished;  }    inline BOOL Suspended() { return m_bSuspended; }    HX_RESULT SetCompressedBufferSize(INT32 lSize);    HX_RESULT InitDecompress(INT32 lMinCodeBits);    HX_RESULT AppendCompressedBuffer(BYTE *pBuffer, INT32 lBufLen);    HX_RESULT LZWReadByte(INT32 &rlSymbol);};#endif