ico.cpp
/*
* $Id: ico.cpp 392281 2005-02-22 16:29:46Z orlovich $
* kimgio import filter for MS Windows .ico files
*
* Distributed under the terms of the LGPL
* Copyright (c) 2000 Malte Starostik <malte@kde.org>
*
*/
#include <cstring>
#include <cstdlib>
#include <algorithm>
#include <vector>
#include <qimage.h>
#include <qbitmap.h>
#include <qapplication.h>
#include <qmemarray.h>
#include <qpaintdevicemetrics.h>
#include <kdelibs_export.h>
#include "ico.h"
namespace
{
// Global header
struct IcoHeader
{
enum Type { Icon = 1, Cursor };
Q_UINT16 reserved;
Q_UINT16 type;
Q_UINT16 count;
};
inline QDataStream& operator >>( QDataStream& s, IcoHeader& h )
{
return s >> h.reserved >> h.type >> h.count;
}
// Based on qt_read_dib et al. from qimage.cpp
// (c) 1992-2002 Trolltech AS.
struct BMP_INFOHDR
{
static const Q_UINT32 Size = 40;
Q_UINT32 biSize; // size of this struct
Q_UINT32 biWidth; // pixmap width
Q_UINT32 biHeight; // pixmap height
Q_UINT16 biPlanes; // should be 1
Q_UINT16 biBitCount; // number of bits per pixel
enum Compression { RGB = 0 };
Q_UINT32 biCompression; // compression method
Q_UINT32 biSizeImage; // size of image
Q_UINT32 biXPelsPerMeter; // horizontal resolution
Q_UINT32 biYPelsPerMeter; // vertical resolution
Q_UINT32 biClrUsed; // number of colors used
Q_UINT32 biClrImportant; // number of important colors
};
const Q_UINT32 BMP_INFOHDR::Size;
QDataStream& operator >>( QDataStream &s, BMP_INFOHDR &bi )
{
s >> bi.biSize;
if ( bi.biSize == BMP_INFOHDR::Size )
{
s >> bi.biWidth >> bi.biHeight >> bi.biPlanes >> bi.biBitCount;
s >> bi.biCompression >> bi.biSizeImage;
s >> bi.biXPelsPerMeter >> bi.biYPelsPerMeter;
s >> bi.biClrUsed >> bi.biClrImportant;
}
return s;
}
#if 0
QDataStream &operator<<( QDataStream &s, const BMP_INFOHDR &bi )
{
s << bi.biSize;
s << bi.biWidth << bi.biHeight;
s << bi.biPlanes;
s << bi.biBitCount;
s << bi.biCompression;
s << bi.biSizeImage;
s << bi.biXPelsPerMeter << bi.biYPelsPerMeter;
s << bi.biClrUsed << bi.biClrImportant;
return s;
}
#endif
// Header for every icon in the file
struct IconRec
{
unsigned char width;
unsigned char height;
Q_UINT16 colors;
Q_UINT16 hotspotX;
Q_UINT16 hotspotY;
Q_UINT32 size;
Q_UINT32 offset;
};
inline QDataStream& operator >>( QDataStream& s, IconRec& r )
{
return s >> r.width >> r.height >> r.colors
>> r.hotspotX >> r.hotspotY >> r.size >> r.offset;
}
struct LessDifference
{
LessDifference( unsigned s, unsigned c )
: size( s ), colors( c ) {}
bool operator ()( const IconRec& lhs, const IconRec& rhs ) const
{
// closest size match precedes everything else
if ( std::abs( int( lhs.width - size ) ) <
std::abs( int( rhs.width - size ) ) ) return true;
else if ( std::abs( int( lhs.width - size ) ) >
std::abs( int( rhs.width - size ) ) ) return false;
else if ( colors == 0 )
{
// high/true color requested
if ( lhs.colors == 0 ) return true;
else if ( rhs.colors == 0 ) return false;
else return lhs.colors > rhs.colors;
}
else
{
// indexed icon requested
if ( lhs.colors == 0 && rhs.colors == 0 ) return false;
else if ( lhs.colors == 0 ) return false;
else return std::abs( int( lhs.colors - colors ) ) <
std::abs( int( rhs.colors - colors ) );
}
}
unsigned size;
unsigned colors;
};
bool loadFromDIB( QDataStream& stream, const IconRec& rec, QImage& icon )
{
BMP_INFOHDR header;
stream >> header;
if ( stream.atEnd() || header.biSize != BMP_INFOHDR::Size ||
header.biSize > rec.size ||
header.biCompression != BMP_INFOHDR::RGB ||
( header.biBitCount != 1 && header.biBitCount != 4 &&
header.biBitCount != 8 && header.biBitCount != 24 &&
header.biBitCount != 32 ) ) return false;
unsigned paletteSize, paletteEntries;
if (header.biBitCount > 8)
{
paletteEntries = 0;
paletteSize = 0;
}
else
{
paletteSize = (1 << header.biBitCount);
paletteEntries = paletteSize;
if (header.biClrUsed && header.biClrUsed < paletteSize)
paletteEntries = header.biClrUsed;
}
// Always create a 32-bit image to get the mask right
// Note: this is safe as rec.width, rec.height are bytes
icon.create( rec.width, rec.height, 32 );
if ( icon.isNull() ) return false;
icon.setAlphaBuffer( true );
QMemArray< QRgb > colorTable( paletteSize );
colorTable.fill( QRgb( 0 ) );
for ( unsigned i = 0; i < paletteEntries; ++i )
{
unsigned char rgb[ 4 ];
stream.readRawBytes( reinterpret_cast< char* >( &rgb ),
sizeof( rgb ) );
colorTable[ i ] = qRgb( rgb[ 2 ], rgb[ 1 ], rgb[ 0 ] );
}
unsigned bpl = ( rec.width * header.biBitCount + 31 ) / 32 * 4;
unsigned char* buf = new unsigned char[ bpl ];
unsigned char** lines = icon.jumpTable();
for ( unsigned y = rec.height; !stream.atEnd() && y--; )
{
stream.readRawBytes( reinterpret_cast< char* >( buf ), bpl );
unsigned char* pixel = buf;
QRgb* p = reinterpret_cast< QRgb* >( lines[ y ] );
switch ( header.biBitCount )
{
case 1:
for ( unsigned x = 0; x < rec.width; ++x )
*p++ = colorTable[
( pixel[ x / 8 ] >> ( 7 - ( x & 0x07 ) ) ) & 1 ];
break;
case 4:
for ( unsigned x = 0; x < rec.width; ++x )
if ( x & 1 ) *p++ = colorTable[ pixel[ x / 2 ] & 0x0f ];
else *p++ = colorTable[ pixel[ x / 2 ] >> 4 ];
break;
case 8:
for ( unsigned x = 0; x < rec.width; ++x )
*p++ = colorTable[ pixel[ x ] ];
break;
case 24:
for ( unsigned x = 0; x < rec.width; ++x )
*p++ = qRgb( pixel[ 3 * x + 2 ],
pixel[ 3 * x + 1 ],
pixel[ 3 * x ] );
break;
case 32:
for ( unsigned x = 0; x < rec.width; ++x )
*p++ = qRgba( pixel[ 4 * x + 2 ],
pixel[ 4 * x + 1 ],
pixel[ 4 * x ],
pixel[ 4 * x + 3] );
break;
}
}
delete[] buf;
if ( header.biBitCount < 32 )
{
// Traditional 1-bit mask
bpl = ( rec.width + 31 ) / 32 * 4;
buf = new unsigned char[ bpl ];
for ( unsigned y = rec.height; y--; )
{
stream.readRawBytes( reinterpret_cast< char* >( buf ), bpl );
QRgb* p = reinterpret_cast< QRgb* >( lines[ y ] );
for ( unsigned x = 0; x < rec.width; ++x, ++p )
if ( ( ( buf[ x / 8 ] >> ( 7 - ( x & 0x07 ) ) ) & 1 ) )
*p &= RGB_MASK;
}
delete[] buf;
}
return true;
}
}
extern "C" KDE_EXPORT void kimgio_ico_read( QImageIO* io )
{
QIODevice::Offset offset = io->ioDevice()->at();
QDataStream stream( io->ioDevice() );
stream.setByteOrder( QDataStream::LittleEndian );
IcoHeader header;
stream >> header;
if ( stream.atEnd() || !header.count ||
( header.type != IcoHeader::Icon && header.type != IcoHeader::Cursor) )
return;
QPaintDeviceMetrics metrics( QApplication::desktop() );
unsigned requestedSize = 32;
unsigned requestedColors = metrics.depth() > 8 ? 0 : metrics.depth();
int requestedIndex = -1;
if ( io->parameters() )
{
QStringList params = QStringList::split( ';', io->parameters() );
QMap< QString, QString > options;
for ( QStringList::ConstIterator it = params.begin();
it != params.end(); ++it )
{
QStringList tmp = QStringList::split( '=', *it );
if ( tmp.count() == 2 ) options[ tmp[ 0 ] ] = tmp[ 1 ];
}
if ( options[ "index" ].toUInt() )
requestedIndex = options[ "index" ].toUInt();
if ( options[ "size" ].toUInt() )
requestedSize = options[ "size" ].toUInt();
if ( options[ "colors" ].toUInt() )
requestedColors = options[ "colors" ].toUInt();
}
typedef std::vector< IconRec > IconList;
IconList icons;
for ( unsigned i = 0; i < header.count; ++i )
{
if ( stream.atEnd() ) return;
IconRec rec;
stream >> rec;
icons.push_back( rec );
}
IconList::const_iterator selected;
if (requestedIndex >= 0) {
selected = std::min( icons.begin() + requestedIndex, icons.end() );
} else {
selected = std::min_element( icons.begin(), icons.end(),
LessDifference( requestedSize, requestedColors ) );
}
if ( stream.atEnd() || selected == icons.end() ||
offset + selected->offset > io->ioDevice()->size() )
return;
io->ioDevice()->at( offset + selected->offset );
QImage icon;
if ( loadFromDIB( stream, *selected, icon ) )
{
icon.setText( "X-Index", 0, QString::number( selected - icons.begin() ) );
if ( header.type == IcoHeader::Cursor )
{
icon.setText( "X-HotspotX", 0, QString::number( selected->hotspotX ) );
icon.setText( "X-HotspotY", 0, QString::number( selected->hotspotY ) );
}
io->setImage(icon);
io->setStatus(0);
}
}
#if 0
void kimgio_ico_write(QImageIO *io)
{
if (io->image().isNull())
return;
QByteArray dibData;
QDataStream dib(dibData, IO_ReadWrite);
dib.setByteOrder(QDataStream::LittleEndian);
QImage pixels = io->image();
QImage mask;
if (io->image().hasAlphaBuffer())
mask = io->image().createAlphaMask();
else
mask = io->image().createHeuristicMask();
mask.invertPixels();
for ( int y = 0; y < pixels.height(); ++y )
for ( int x = 0; x < pixels.width(); ++x )
if ( mask.pixel( x, y ) == 0 ) pixels.setPixel( x, y, 0 );
if (!qt_write_dib(dib, pixels))
return;
uint hdrPos = dib.device()->at();
if (!qt_write_dib(dib, mask))
return;
memmove(dibData.data() + hdrPos, dibData.data() + hdrPos + BMP_WIN + 8, dibData.size() - hdrPos - BMP_WIN - 8);
dibData.resize(dibData.size() - BMP_WIN - 8);
QDataStream ico(io->ioDevice());
ico.setByteOrder(QDataStream::LittleEndian);
IcoHeader hdr;
hdr.reserved = 0;
hdr.type = Icon;
hdr.count = 1;
ico << hdr.reserved << hdr.type << hdr.count;
IconRec rec;
rec.width = io->image().width();
rec.height = io->image().height();
if (io->image().numColors() <= 16)
rec.colors = 16;
else if (io->image().depth() <= 8)
rec.colors = 256;
else
rec.colors = 0;
rec.hotspotX = 0;
rec.hotspotY = 0;
rec.dibSize = dibData.size();
ico << rec.width << rec.height << rec.colors
<< rec.hotspotX << rec.hotspotY << rec.dibSize;
rec.dibOffset = ico.device()->at() + sizeof(rec.dibOffset);
ico << rec.dibOffset;
BMP_INFOHDR dibHeader;
dib.device()->at(0);
dib >> dibHeader;
dibHeader.biHeight = io->image().height() << 1;
dib.device()->at(0);
dib << dibHeader;
ico.writeRawBytes(dibData.data(), dibData.size());
io->setStatus(0);
}
#endif

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