mirror of
https://github.com/martravi/wiiqt.git
synced 2024-11-22 17:19:18 +01:00
394 lines
7.2 KiB
C++
394 lines
7.2 KiB
C++
#include "lz77.h"
|
|
|
|
//most functions here are taken from wii.cs by leathl
|
|
//they have just been tweeked slightly to work with Qt C++
|
|
|
|
LZ77::LZ77()
|
|
{
|
|
match_position = 0;
|
|
match_length = 0;
|
|
textsize = 0;
|
|
codesize = 0;
|
|
}
|
|
|
|
int LZ77::GetLz77Offset( const QByteArray &data )
|
|
{
|
|
QByteArray start = data.left( 5000 );
|
|
|
|
return start.indexOf( "LZ77" );
|
|
}
|
|
|
|
void LZ77::InitTree()
|
|
{
|
|
int i;
|
|
int N = 4096;
|
|
for( i = N + 1; i <= N + 256; i++ )
|
|
rson[ i ] = N;
|
|
|
|
for( i = 0; i < N; i++ )
|
|
dad[ i ] = N;
|
|
}
|
|
|
|
void LZ77::DeleteNode( int p )
|
|
{
|
|
int N = 4096;
|
|
int q;
|
|
|
|
if( dad[ p ] == N )
|
|
return; /* not in tree */
|
|
|
|
if( rson[ p ] == N )
|
|
q = lson[ p ];
|
|
|
|
else if( lson[ p ] == N )
|
|
q = rson[ p ];
|
|
|
|
else
|
|
{
|
|
q = lson[ p ];
|
|
|
|
if( rson[ q ] != N )
|
|
{
|
|
do
|
|
{
|
|
q = rson[ q ];
|
|
}
|
|
while( rson[ q ] != N );
|
|
|
|
rson[ dad[ q ] ] = lson[ q ];
|
|
dad[ lson[ q ] ] = dad[ q ];
|
|
|
|
lson[ q ] = lson[ p ];
|
|
dad[ lson[ p ] ] = q;
|
|
}
|
|
rson[ q ] = rson[ p ];
|
|
dad[ rson[ p ] ] = q;
|
|
}
|
|
dad[ q ] = dad[ p ];
|
|
|
|
if( rson[ dad[ p ] ] == p )
|
|
rson[ dad[ p ] ] = q;
|
|
else
|
|
lson[ dad[ p ] ] = q;
|
|
|
|
dad[ p ] = N;
|
|
}
|
|
|
|
void LZ77::InsertNode( int r )
|
|
{
|
|
int i, p, cmp;
|
|
int N = 4096;
|
|
int F = 18;
|
|
cmp = 1;
|
|
p = N + 1 + ( text_buf[ r ] == ( quint16 )0xffff ? ( quint16 )0 : text_buf[ r ] );
|
|
rson[ r ] = lson[ r ] = N;
|
|
match_length = 0;
|
|
for( ; ; )
|
|
{
|
|
if( cmp >= 0 )
|
|
{
|
|
if( rson[ p ] != N )
|
|
p = rson[ p ];
|
|
else
|
|
{
|
|
rson[ p ] = r;
|
|
dad[ r ] = p;
|
|
return;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if ( lson[ p ] != N )
|
|
p = lson[ p ];
|
|
|
|
else
|
|
{
|
|
lson[ p ] = r;
|
|
dad[ r ] = p;
|
|
return;
|
|
}
|
|
}
|
|
for( i = 1; i < F; i++ )
|
|
if( ( cmp = text_buf[ r + i ] - text_buf[ p + i ] ) != 0 )
|
|
break;
|
|
if( i > match_length )
|
|
{
|
|
match_position = p;
|
|
if( ( match_length = i ) >= F )
|
|
break;
|
|
}
|
|
}
|
|
|
|
dad[ r ] = dad[ p ];
|
|
lson[ r ] = lson[ p ];
|
|
rson[ r ] = rson[ p ];
|
|
dad[ lson[ p ] ] = r;
|
|
dad[ rson[ p ] ] = r;
|
|
|
|
if( rson[ dad[ p ] ] == p )
|
|
rson[ dad[ p ] ] = r;
|
|
|
|
else
|
|
lson[ dad[ p ] ] = r;
|
|
|
|
dad[ p ] = N;
|
|
}
|
|
|
|
quint32 LZ77::GetDecompressedSize( const QByteArray &data )
|
|
{
|
|
int off = GetLz77Offset( data );
|
|
if( off == -1 )
|
|
{
|
|
qWarning() << "LZ77::GetDecompressedSize -> no lz77 magic";
|
|
return 0;
|
|
}
|
|
QByteArray ba = data;
|
|
QBuffer buf( &ba );
|
|
if( !buf.open( QBuffer::ReadOnly ) )
|
|
{
|
|
qWarning() << "LZ77::GetDecompressedSize -> Can't create buffer";
|
|
return 0;
|
|
}
|
|
buf.seek( off + 4 );
|
|
|
|
quint32 gbaheader;
|
|
buf.seek( off + 4 );
|
|
buf.read( (char*)&gbaheader, 4 );
|
|
|
|
return ( gbaheader >> 8 );
|
|
}
|
|
|
|
QByteArray LZ77::Decompress( const QByteArray &compressed, int offset )
|
|
{
|
|
int N = 4096;
|
|
int F = 18;
|
|
int threshold = 2;
|
|
int k, r, z, flags;
|
|
quint16 i, j;
|
|
char ch;
|
|
quint32 decomp_size;
|
|
quint32 cur_size = 0;
|
|
|
|
QByteArray crap = compressed;
|
|
QBuffer infile( &crap );
|
|
if( !infile.open( QBuffer::ReadOnly ) )
|
|
{
|
|
qWarning() << "Can't create buffer 1";
|
|
return QByteArray();
|
|
}
|
|
QByteArray ret;
|
|
QBuffer outfile( &ret );
|
|
if( !outfile.open( QBuffer::ReadWrite ) )
|
|
{
|
|
qWarning() << "Can't create buffer 2";
|
|
return QByteArray();
|
|
}
|
|
|
|
quint32 gbaheader;
|
|
infile.seek( offset + 4 );
|
|
infile.read( (char*)&gbaheader, 4 );
|
|
|
|
decomp_size = gbaheader >> 8;
|
|
quint8 text_buf[ N + 17 ];
|
|
|
|
for( i = 0; i < N - F; i++ )
|
|
text_buf[ i ] = 0xdf;
|
|
|
|
r = N - F;
|
|
flags = 7;
|
|
z = 7;
|
|
|
|
while( true )
|
|
{
|
|
flags <<= 1;
|
|
z++;
|
|
if( z == 8 )
|
|
{
|
|
if( !infile.getChar( &ch ) )
|
|
break;
|
|
flags = (quint8) ch;
|
|
z = 0;
|
|
}
|
|
if( ( flags & 0x80 ) == 0 )
|
|
{
|
|
if( !infile.getChar( &ch ) )
|
|
break;
|
|
|
|
if( cur_size < decomp_size )
|
|
outfile.putChar( ch );
|
|
|
|
text_buf[ r++ ] = ch;
|
|
r &= ( N - 1 );
|
|
cur_size++;
|
|
}
|
|
else
|
|
{
|
|
if( !infile.getChar( &ch ) )
|
|
break;
|
|
i = (quint8)ch;
|
|
|
|
if( !infile.getChar( &ch ) )
|
|
break;
|
|
j = (quint8)ch;
|
|
|
|
j = j | ( (i << 8) & 0xf00 );
|
|
i = ( ( i >> 4 ) & 0x0f ) + threshold;
|
|
|
|
for( k = 0; k <= i; k++ )
|
|
{
|
|
ch = text_buf[ ( r - j - 1 ) & ( N - 1 ) ];
|
|
if( cur_size < decomp_size )
|
|
outfile.putChar( ch );
|
|
|
|
text_buf[ r++ ] = ch;
|
|
r &= ( N - 1 );
|
|
cur_size++;
|
|
}
|
|
}
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
QByteArray LZ77::Decompress( const QByteArray &compressed )
|
|
{
|
|
int off = GetLz77Offset( compressed );
|
|
if( off < 0 )
|
|
{
|
|
qWarning() << "LZ77::Decompress -> data is not compressed";
|
|
return compressed;
|
|
}
|
|
return Decompress( compressed, off );
|
|
}
|
|
|
|
QByteArray LZ77::Compress( const QByteArray &ba )
|
|
{
|
|
//testing 1, 2
|
|
//return ba;
|
|
LZ77 lz;
|
|
QByteArray ret = lz.Compr( ba );
|
|
return ret;
|
|
}
|
|
|
|
QByteArray LZ77::Compr( const QByteArray &ba )
|
|
{
|
|
int i, len, r, s, last_match_length, code_buf_ptr;
|
|
char ch;
|
|
int code_buf[ 17 ];
|
|
int mask;
|
|
int N = 4096;
|
|
int F = 18;
|
|
int threshold = 2;
|
|
quint32 filesize = (ba.size() << 8) + 0x10;
|
|
|
|
QByteArray crap = ba;
|
|
QBuffer infile( &crap );
|
|
if( !infile.open( QBuffer::ReadOnly ) )
|
|
{
|
|
qWarning() << "Can't create buffer 1";
|
|
return QByteArray();
|
|
}
|
|
QByteArray ret;
|
|
QBuffer output( &ret );
|
|
if( !output.open( QBuffer::ReadWrite ) )
|
|
{
|
|
qWarning() << "Can't create buffer 2";
|
|
return QByteArray();
|
|
}
|
|
output.putChar( 'L' );
|
|
output.putChar( 'Z' );
|
|
output.putChar( '7' );
|
|
output.putChar( '7' );
|
|
|
|
output.write( (const char*)&filesize, 4 );
|
|
|
|
InitTree();
|
|
code_buf[ 0 ] = 0;
|
|
code_buf_ptr = 1;
|
|
mask = 0x80;
|
|
s = 0;
|
|
r = N - F;
|
|
|
|
for( i = s; i < r; i++ )
|
|
text_buf[ i ] = 0xffff;
|
|
|
|
for( len = 0; len < F && infile.getChar( &ch ); len++ )
|
|
text_buf[ r + len ] = (quint8)ch;
|
|
|
|
if( ( textsize = len ) == 0)
|
|
return ba;
|
|
|
|
for( i = 1; i <= F; i++ )
|
|
InsertNode( r - i );
|
|
|
|
InsertNode( r );
|
|
|
|
do
|
|
{
|
|
if( match_length > len )
|
|
match_length = len;
|
|
|
|
if( match_length <= threshold )
|
|
{
|
|
match_length = 1;
|
|
code_buf[ code_buf_ptr++ ] = text_buf[ r ];
|
|
}
|
|
else
|
|
{
|
|
code_buf[ 0 ] |= mask;
|
|
|
|
code_buf[ code_buf_ptr++ ] = (quint8)
|
|
( ( ( r - match_position - 1 ) >> 8) & 0x0f ) |
|
|
( ( match_length - ( threshold + 1 ) ) << 4 );
|
|
|
|
code_buf[ code_buf_ptr++ ] = (quint8)( ( r - match_position - 1 ) & 0xff );
|
|
}
|
|
if( ( mask >>= 1 ) == 0 )
|
|
{
|
|
for( i = 0; i < code_buf_ptr; i++ )
|
|
output.putChar( (quint8)code_buf[ i ] );
|
|
|
|
codesize += code_buf_ptr;
|
|
code_buf[ 0 ] = 0; code_buf_ptr = 1;
|
|
mask = 0x80;
|
|
}
|
|
|
|
last_match_length = match_length;
|
|
for( i = 0; i < last_match_length && infile.getChar( &ch ); i++ )
|
|
{
|
|
DeleteNode( s );
|
|
text_buf[ s ] = (quint8)ch;
|
|
if( s < F - 1 )
|
|
text_buf[ s + N ] = (quint8)ch;
|
|
|
|
s = ( s + 1 ) & ( N - 1 );
|
|
r = ( r + 1 ) & ( N - 1 );
|
|
InsertNode( r );
|
|
}
|
|
|
|
while( i++ < last_match_length )
|
|
{
|
|
DeleteNode( s );
|
|
s = ( s + 1 ) & ( N - 1 );
|
|
r = ( r + 1 ) & ( N - 1 );
|
|
if( --len != 0 )
|
|
InsertNode( r );
|
|
}
|
|
}
|
|
while( len > 0 );
|
|
|
|
if( code_buf_ptr > 1 )
|
|
{
|
|
for( i = 0; i < code_buf_ptr; i++ )
|
|
output.putChar( (quint8)code_buf[ i ] );
|
|
|
|
codesize += code_buf_ptr;
|
|
}
|
|
int padding = codesize % 4;
|
|
if( padding != 0 )
|
|
output.write( QByteArray( 4 - padding, '\0' ) );
|
|
|
|
infile.close();
|
|
return ret;
|
|
}
|