wiiqt/WiiQt/lz77.h

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#ifndef LZ77_H
#define LZ77_H
#include "includes.h"
//class for dealing with LZ77 compression (version 0x10)
//! in most cases, you just want to use the static functions
// QByteArray stuff = LZ77::Decompress( someCompressedData );
// QByteArray compressedData = LZ77::Compress( someData );
class LZ77
{
public:
enum CompressionType
{
None, // not compressed
v10, // version 0x10
v11, // version 0x11
v10_w_magic // version 0x10 with "LZ77" magic bytes
};
LZ77();
void InsertNode( int r );
void DeleteNode( int p );
void InitTree();
//gets the offset in a bytearray of the lz77 magic word
static int GetLz77Offset( const QByteArray &data );
//gets the decompressed size of a lz77 compressed buffer
static quint32 GetDecompressedSize( const QByteArray &data );
//decompress a buffer that is compressed with the 0x10 variant
static QByteArray Decompress_v10( const QByteArray &compressed, int offset );
static QByteArray Compress( const QByteArray &ba, CompressionType type );
//compressed a qbytearray with the lz77 argorythm
//returns a qbytearray ncluding the lz77 header
static QByteArray Compress_v10( const QByteArray &ba, bool addMagic = true );
//check the type of archive, and get theoffset of the "LZ77" magic word in the case of v10_w_magic
static CompressionType GetCompressedType( const QByteArray &data, int *outOffset = NULL );
// decompress data and get whatever type of compression was used on the data
static QByteArray Decompress( const QByteArray &stuff, CompressionType *outType = NULL );
private:
int lson[ 4097 ];
int rson[ 4353 ];
int dad[ 4097 ];
quint16 text_buf[ 4113 ];
int match_position;
int match_length;
int textsize;
int codesize;
//used internally by the static compression function
QByteArray Compr_v10( const QByteArray &ba, bool addMagic = true );
};
class LZ77_11
{
public:
LZ77_11();
static QByteArray Compress( const QByteArray &stuff );
static QByteArray Decompress( const QByteArray stuff );
};
class LzWindowDictionary
{
public:
LzWindowDictionary();
QList<int> Search( const QByteArray &DecompressedData, quint32 offset, quint32 length );
void SlideWindow( int Amount );
void SlideBlock();
void RemoveOldEntries( quint8 index );
void SetWindowSize( int size );
void SetMinMatchAmount( int amount );
void SetMaxMatchAmount( int amount );
void SetBlockSize( int size );
void AddEntry( const QByteArray &DecompressedData, int offset );
void AddEntryRange( const QByteArray &DecompressedData, int offset, int length );
private:
int WindowSize;
int WindowStart;
int WindowLength;
int MinMatchAmount;
int MaxMatchAmount;
int BlockSize;
QList<int> OffsetList[ 0x100 ];
};
#endif // LZ77_H