ccidecom.hxx

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#ifndef INCLUDED_FILTER_SOURCE_GRAPHICFILTER_ITIFF_CCIDECOM_HXX
#define INCLUDED_FILTER_SOURCE_GRAPHICFILTER_ITIFF_CCIDECOM_HXX

#include <sal/types.h>
#include <array>
#include <memory>

#define CCI_OPTION_2D               1       // 2D compression (instead of 1D)
#define CCI_OPTION_EOL              2       // There are EOL-Codes at the end of each line.
#define CCI_OPTION_BYTEALIGNEOL     4       // Filling bits before each EOL-Code, so that
                                            // the end of EOL is bytes aligned
#define CCI_OPTION_BYTEALIGNROW     8       // Rows always start byte aligned
#define CCI_OPTION_INVERSEBITORDER  16

// Entry in the Huffman table:
struct CCIHuffmanTableEntry {
    sal_uInt16 nValue;    // The data value.
    sal_uInt16 nCode;     // The code through which the data value is represented.
    sal_uInt16 nCodeBits; // Size of the code in bits.
};

// Entry in a hash table for daft decoding.
struct CCILookUpTableEntry {
    sal_uInt16 nValue;
    sal_uInt16 nCodeBits;
};

class SvStream;

struct DecompressStatus
{
    bool m_bSuccess;
    bool m_bBufferUnchanged;
    DecompressStatus(bool bSuccess, bool bBufferUnchanged)
        : m_bSuccess(bSuccess), m_bBufferUnchanged(bBufferUnchanged)
    {
    }
};

class CCIDecompressor {

public:

    CCIDecompressor( sal_uInt32 nOptions, sal_uInt32 nImageWidth );
    ~CCIDecompressor();

    void StartDecompression( SvStream & rIStream );

    DecompressStatus DecompressScanline(sal_uInt8 * pTarget, sal_uInt64 nTargetBits, bool bLastLine);

private:

    void MakeLookUp(const CCIHuffmanTableEntry * pHufTab,
                    const CCIHuffmanTableEntry * pHufTabSave,
                    CCILookUpTableEntry * pLookUp,
                    sal_uInt16 nHuffmanTableSize,
                    sal_uInt16 nMaxCodeBits);

    bool ReadEOL();

    bool Read2DTag();

    sal_uInt8 ReadBlackOrWhite();

    sal_uInt16 ReadCodeAndDecode(const CCILookUpTableEntry * pLookUp,
                             sal_uInt16 nMaxCodeBits);

    static void FillBits(sal_uInt8 * pTarget, sal_uInt16 nTargetBits,
                  sal_uInt16 nBitPos, sal_uInt16 nNumBits,
                  sal_uInt8 nBlackOrWhite);

    static sal_uInt16 CountBits(const sal_uInt8 * pData, sal_uInt16 nDataSizeBits,
                     sal_uInt16 nBitPos, sal_uInt8 nBlackOrWhite);

    //returns true if pTarget was unmodified
    bool Read1DScanlineData(sal_uInt8 * pTarget, sal_uInt16 nTargetBits);
    bool Read2DScanlineData(sal_uInt8 * pTarget, sal_uInt16 nTargetBits);

    bool bTableBad;

    bool bStatus;

    std::unique_ptr<sal_uInt8[]> pByteSwap;

    SvStream * pIStream;

    sal_uInt32 nEOLCount;

    sal_uInt32 nWidth;

    sal_uInt32 nOptions;

    bool bFirstEOL;

    std::array<CCILookUpTableEntry, 1<<13> pWhiteLookUp;
    std::array<CCILookUpTableEntry, 1<<13> pBlackLookUp;
    std::array<CCILookUpTableEntry, 1<<10> p2DModeLookUp;
    std::array<CCILookUpTableEntry, 1<<11> pUncompLookUp;

    sal_uInt32 nInputBitsBuf;
    sal_uInt16 nInputBitsBufSize;

    std::unique_ptr<sal_uInt8[]> pLastLine;
    sal_uInt64 nLastLineSize;
};


#endif

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