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|
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*************************************************************************
*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* Copyright 2000, 2010 Oracle and/or its affiliates.
*
* OpenOffice.org - a multi-platform office productivity suite
*
* This file is part of OpenOffice.org.
*
* OpenOffice.org is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version 3
* only, as published by the Free Software Foundation.
*
* OpenOffice.org is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License version 3 for more details
* (a copy is included in the LICENSE file that accompanied this code).
*
* You should have received a copy of the GNU Lesser General Public License
* version 3 along with OpenOffice.org. If not, see
* <http://www.openoffice.org/license.html>
* for a copy of the LGPLv3 License.
*
************************************************************************/
#include <vcl/pngread.hxx>
#include <cmath>
#include <rtl/crc.h>
#include <rtl/memory.h>
#include <rtl/alloc.h>
#include <tools/zcodec.hxx>
#include <tools/stream.hxx>
#include <vcl/bmpacc.hxx>
#include <vcl/svapp.hxx>
#include <vcl/alpha.hxx>
#include <osl/endian.h>
// -----------
// - Defines -
// -----------
#define PNGCHUNK_IHDR 0x49484452
#define PNGCHUNK_PLTE 0x504c5445
#define PNGCHUNK_IDAT 0x49444154
#define PNGCHUNK_IEND 0x49454e44
#define PNGCHUNK_bKGD 0x624b4744
#define PNGCHUNK_cHRM 0x6348524d
#define PNGCHUNK_gAMA 0x67414d41
#define PNGCHUNK_hIST 0x68495354
#define PNGCHUNK_pHYs 0x70485973
#define PNGCHUNK_sBIT 0x73425420
#define PNGCHUNK_tIME 0x74494d45
#define PNGCHUNK_tEXt 0x74455874
#define PNGCHUNK_tRNS 0x74524e53
#define PNGCHUNK_zTXt 0x7a545874
#define PMGCHUNG_msOG 0x6d734f47 // Microsoft Office Animated GIF
#define VIEWING_GAMMA 2.35
#define DISPLAY_GAMMA 1.0
namespace vcl
{
// -----------
// - statics -
// -----------
// ------------------------------------------------------------------------------
static const sal_uInt8 mpDefaultColorTable[ 256 ] =
{ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,
0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf,
0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf,
0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf,
0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf,
0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef,
0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff
};
// -------------
// - PNGReaderImpl -
// -------------
class PNGReaderImpl
{
private:
SvStream& mrPNGStream;
sal_uInt16 mnOrigStreamMode;
std::vector< vcl::PNGReader::ChunkData > maChunkSeq;
std::vector< vcl::PNGReader::ChunkData >::iterator maChunkIter;
std::vector< sal_uInt8 >::iterator maDataIter;
Bitmap* mpBmp;
BitmapWriteAccess* mpAcc;
Bitmap* mpMaskBmp;
AlphaMask* mpAlphaMask;
BitmapWriteAccess* mpMaskAcc;
ZCodec* mpZCodec;
sal_uInt8* mpInflateInBuf; // as big as the size of a scanline + alphachannel + 1
sal_uInt8* mpScanPrior; // pointer to the latest scanline
sal_uInt8* mpTransTab; // for transparency in images with palette colortype
sal_uInt8* mpScanCurrent; // pointer into the current scanline
sal_uInt8* mpColorTable; //
sal_Size mnStreamSize; // estimate of PNG file size
sal_uInt32 mnChunkType; // Type of current PNG chunk
sal_Int32 mnChunkLen; // Length of current PNG chunk
Size maOrigSize; // pixel size of the full image
Size maTargetSize; // pixel size of the result image
Size maPhysSize; // prefered size in MAP_100TH_MM units
sal_uInt32 mnBPP; // number of bytes per pixel
sal_uInt32 mnScansize; // max size of scanline
sal_uInt32 mnYpos; // latest y position in full image
int mnPass; // if interlaced the latest pass ( 1..7 ) else 7
sal_uInt32 mnXStart; // the starting X for the current pass
sal_uInt32 mnXAdd; // the increment for input images X coords for the current pass
sal_uInt32 mnYAdd; // the increment for input images Y coords for the current pass
int mnPreviewShift; // shift to convert orig image coords into preview image coords
int mnPreviewMask; // == ((1 << mnPreviewShift) - 1)
sal_uInt16 mnIStmOldMode;
sal_uInt16 mnTargetDepth; // pixel depth of target bitmap
sal_uInt8 mnTransRed;
sal_uInt8 mnTransGreen;
sal_uInt8 mnTransBlue;
sal_uInt8 mnPngDepth; // pixel depth of PNG data
sal_uInt8 mnColorType;
sal_uInt8 mnCompressionType;
sal_uInt8 mnFilterType;
sal_uInt8 mnInterlaceType;
BitmapColor mcTranspColor; // transparency mask's transparency "color"
BitmapColor mcOpaqueColor; // transparency mask's opaque "color"
sal_Bool mbTransparent; // graphic includes an tRNS Chunk or an alpha Channel
sal_Bool mbAlphaChannel; // is true for ColorType 4 and 6
sal_Bool mbRGBTriple;
sal_Bool mbPalette; // sal_False if we need a Palette
sal_Bool mbGrayScale;
sal_Bool mbzCodecInUse;
sal_Bool mbStatus;
sal_Bool mbIDAT; // sal_True if finished with enough IDAT chunks
sal_Bool mbGamma; // sal_True if Gamma Correction available
sal_Bool mbpHYs; // sal_True if pysical size of pixel available
sal_Bool mbIgnoreGammaChunk;
bool ReadNextChunk();
void ReadRemainingChunks();
void ImplSetPixel( sal_uInt32 y, sal_uInt32 x, const BitmapColor & );
void ImplSetPixel( sal_uInt32 y, sal_uInt32 x, sal_uInt8 nPalIndex );
void ImplSetTranspPixel( sal_uInt32 y, sal_uInt32 x, const BitmapColor &, sal_Bool bTrans );
void ImplSetAlphaPixel( sal_uInt32 y, sal_uInt32 x, sal_uInt8 nPalIndex, sal_uInt8 nAlpha );
void ImplSetAlphaPixel( sal_uInt32 y, sal_uInt32 x, const BitmapColor&, sal_uInt8 nAlpha );
void ImplReadIDAT();
bool ImplPreparePass();
void ImplApplyFilter();
void ImplDrawScanline( sal_uInt32 nXStart, sal_uInt32 nXAdd );
sal_Bool ImplReadTransparent();
void ImplGetGamma();
void ImplGetBackground();
sal_uInt8 ImplScaleColor();
sal_Bool ImplReadHeader( const Size& rPreviewSizeHint );
sal_Bool ImplReadPalette();
void ImplGetGrayPalette( sal_uInt16 );
sal_uInt32 ImplReadsal_uInt32();
public:
PNGReaderImpl( SvStream& );
~PNGReaderImpl();
BitmapEx GetBitmapEx( const Size& rPreviewSizeHint );
const std::vector< PNGReader::ChunkData >& GetAllChunks();
void SetIgnoreGammaChunk( sal_Bool bIgnore ){ mbIgnoreGammaChunk = bIgnore; };
};
// ------------------------------------------------------------------------------
PNGReaderImpl::PNGReaderImpl( SvStream& rPNGStream )
: mrPNGStream( rPNGStream ),
mpBmp ( NULL ),
mpAcc ( NULL ),
mpMaskBmp ( NULL ),
mpAlphaMask ( NULL ),
mpMaskAcc ( NULL ),
mpZCodec ( new ZCodec( DEFAULT_IN_BUFSIZE, DEFAULT_OUT_BUFSIZE, MAX_MEM_USAGE ) ),
mpInflateInBuf ( NULL ),
mpScanPrior ( NULL ),
mpTransTab ( NULL ),
mpScanCurrent ( NULL ),
mpColorTable ( (sal_uInt8*) mpDefaultColorTable ),
mnPass ( 0 ),
mbzCodecInUse ( sal_False ),
mbStatus( sal_True),
mbIDAT( sal_False ),
mbGamma ( sal_False ),
mbpHYs ( sal_False ),
mbIgnoreGammaChunk ( sal_False )
{
// prepare the PNG data stream
mnOrigStreamMode = mrPNGStream.GetNumberFormatInt();
mrPNGStream.SetNumberFormatInt( NUMBERFORMAT_INT_BIGENDIAN );
// prepare the chunk reader
maChunkSeq.reserve( 16 );
maChunkIter = maChunkSeq.begin();
// estimate PNG file size (to allow sanity checks)
const sal_Size nStreamPos = mrPNGStream.Tell();
mrPNGStream.Seek( STREAM_SEEK_TO_END );
mnStreamSize = mrPNGStream.Tell();
mrPNGStream.Seek( nStreamPos );
// check the PNG header magic
sal_uInt32 nDummy = 0;
mrPNGStream >> nDummy;
mbStatus = (nDummy == 0x89504e47);
mrPNGStream >> nDummy;
mbStatus &= (nDummy == 0x0d0a1a0a);
mnPreviewShift = 0;
mnPreviewMask = (1 << mnPreviewShift) - 1;
}
// ------------------------------------------------------------------------
PNGReaderImpl::~PNGReaderImpl()
{
mrPNGStream.SetNumberFormatInt( mnOrigStreamMode );
if ( mbzCodecInUse )
mpZCodec->EndCompression();
if( mpColorTable != mpDefaultColorTable )
delete[] mpColorTable;
delete mpBmp;
delete mpAlphaMask;
delete mpMaskBmp;
delete[] mpTransTab;
delete[] mpInflateInBuf;
delete[] mpScanPrior;
delete mpZCodec;
}
// ------------------------------------------------------------------------
bool PNGReaderImpl::ReadNextChunk()
{
if( maChunkIter == maChunkSeq.end() )
{
// get the next chunk from the stream
// unless we are at the end of the PNG stream
if( mrPNGStream.IsEof() || (mrPNGStream.GetError() != ERRCODE_NONE) )
return false;
if( !maChunkSeq.empty() && (maChunkSeq.back().nType == PNGCHUNK_IEND) )
return false;
PNGReader::ChunkData aDummyChunk;
maChunkIter = maChunkSeq.insert( maChunkSeq.end(), aDummyChunk );
PNGReader::ChunkData& rChunkData = *maChunkIter;
// read the chunk header
mrPNGStream >> mnChunkLen >> mnChunkType;
rChunkData.nType = mnChunkType;
// #128377#/#149343# sanity check for chunk length
if( mnChunkLen < 0 )
return false;
const sal_Size nStreamPos = mrPNGStream.Tell();
if( nStreamPos + mnChunkLen >= mnStreamSize )
return false;
// calculate chunktype CRC (swap it back to original byte order)
sal_uInt32 nChunkType = mnChunkType;
#if defined(__LITTLEENDIAN) || defined(OSL_LITENDIAN)
nChunkType = OSL_SWAPDWORD( nChunkType );
#endif
sal_uInt32 nCRC32 = rtl_crc32( 0, &nChunkType, 4 );
// read the chunk data and check the CRC
if( mnChunkLen && !mrPNGStream.IsEof() )
{
rChunkData.aData.resize( mnChunkLen );
sal_Int32 nBytesRead = 0;
do {
sal_uInt8* pPtr = &rChunkData.aData[ nBytesRead ];
nBytesRead += mrPNGStream.Read( pPtr, mnChunkLen - nBytesRead );
} while ( ( nBytesRead < mnChunkLen ) && ( mrPNGStream.GetError() == ERRCODE_NONE ) );
nCRC32 = rtl_crc32( nCRC32, &rChunkData.aData[ 0 ], mnChunkLen );
maDataIter = rChunkData.aData.begin();
}
sal_uInt32 nCheck;
mrPNGStream >> nCheck;
if( nCRC32 != nCheck )
return false;
}
else
{
// the next chunk was already read
mnChunkType = (*maChunkIter).nType;
mnChunkLen = (*maChunkIter).aData.size();
maDataIter = (*maChunkIter).aData.begin();
}
++maChunkIter;
if( mnChunkType == PNGCHUNK_IEND )
return false;
return true;
}
// ------------------------------------------------------------------------
// read the remaining chunks from mrPNGStream
void PNGReaderImpl::ReadRemainingChunks()
{
while( ReadNextChunk() ) ;
}
// ------------------------------------------------------------------------
const std::vector< vcl::PNGReader::ChunkData >& PNGReaderImpl::GetAllChunks()
{
ReadRemainingChunks();
return maChunkSeq;
}
// ------------------------------------------------------------------------
BitmapEx PNGReaderImpl::GetBitmapEx( const Size& rPreviewSizeHint )
{
// reset to the first chunk
maChunkIter = maChunkSeq.begin();
// parse the chunks
while( mbStatus && !mbIDAT && ReadNextChunk() )
{
switch( mnChunkType )
{
case PNGCHUNK_IHDR :
{
mbStatus = ImplReadHeader( rPreviewSizeHint );
}
break;
case PNGCHUNK_gAMA : // the gamma chunk must precede
{ // the 'IDAT' and also the 'PLTE'(if available )
if ( !mbIgnoreGammaChunk && ( mbIDAT == sal_False ) )
ImplGetGamma();
}
break;
case PNGCHUNK_PLTE :
{
if ( !mbPalette )
mbStatus = ImplReadPalette();
}
break;
case PNGCHUNK_tRNS :
{
if ( !mbIDAT ) // the tRNS chunk must precede the IDAT
mbStatus = ImplReadTransparent();
}
break;
case PNGCHUNK_bKGD : // the background chunk must appear
{
if ( ( mbIDAT == sal_False ) && mbPalette ) // before the 'IDAT' and after the
ImplGetBackground(); // PLTE(if available ) chunk.
}
break;
case PNGCHUNK_IDAT :
{
if ( !mpInflateInBuf ) // taking care that the header has properly been read
mbStatus = sal_False;
else if ( !mbIDAT ) // the gfx is finished, but there may be left a zlibCRC of about 4Bytes
ImplReadIDAT();
}
break;
case PNGCHUNK_pHYs :
{
if ( !mbIDAT && mnChunkLen == 9 )
{
sal_uInt32 nXPixelPerMeter = ImplReadsal_uInt32();
sal_uInt32 nYPixelPerMeter = ImplReadsal_uInt32();
sal_uInt8 nUnitSpecifier = *maDataIter++;
if( (nUnitSpecifier == 1) && nXPixelPerMeter && nYPixelPerMeter )
{
mbpHYs = sal_True;
// convert into MAP_100TH_MM
maPhysSize.Width() = (sal_Int32)( (100000.0 * maOrigSize.Width()) / nXPixelPerMeter );
maPhysSize.Height() = (sal_Int32)( (100000.0 * maOrigSize.Height()) / nYPixelPerMeter );
}
}
}
break;
case PNGCHUNK_IEND:
mbStatus = mbIDAT; // there is a problem if the image is not complete yet
break;
}
}
// release write access of the bitmaps
if ( mpAcc )
mpBmp->ReleaseAccess( mpAcc ), mpAcc = NULL;
if ( mpMaskAcc )
{
if ( mpAlphaMask )
mpAlphaMask->ReleaseAccess( mpMaskAcc );
else if ( mpMaskBmp )
mpMaskBmp->ReleaseAccess( mpMaskAcc );
mpMaskAcc = NULL;
}
// return the resulting BitmapEx
BitmapEx aRet;
if( !mbStatus || !mbIDAT )
aRet.Clear();
else
{
if ( mpAlphaMask )
aRet = BitmapEx( *mpBmp, *mpAlphaMask );
else if ( mpMaskBmp )
aRet = BitmapEx( *mpBmp, *mpMaskBmp );
else
aRet = *mpBmp;
if ( mbpHYs && maPhysSize.Width() && maPhysSize.Height() )
{
aRet.SetPrefMapMode( MAP_100TH_MM );
aRet.SetPrefSize( maPhysSize );
}
}
return aRet;
}
// ------------------------------------------------------------------------
sal_Bool PNGReaderImpl::ImplReadHeader( const Size& rPreviewSizeHint )
{
if( mnChunkLen < 13 )
return sal_False;
maOrigSize.Width() = ImplReadsal_uInt32();
maOrigSize.Height() = ImplReadsal_uInt32();
if ( !maOrigSize.Width() || !maOrigSize.Height() )
return sal_False;
mnPngDepth = *(maDataIter++);
mnColorType = *(maDataIter++);
mnCompressionType = *(maDataIter++);
if( mnCompressionType != 0 ) // unknown compression type
return sal_False;
mnFilterType = *(maDataIter++);
if( mnFilterType != 0 ) // unknown filter type
return sal_False;
mnInterlaceType = *(maDataIter++);
switch ( mnInterlaceType ) // filter type valid ?
{
case 0 : // progressive image
mnPass = 7;
break;
case 1 : // Adam7-interlaced image
mnPass = 0;
break;
default:
return sal_False;
}
mbPalette = sal_True;
mbIDAT = mbAlphaChannel = mbTransparent = sal_False;
mbGrayScale = mbRGBTriple = sal_False;
mnTargetDepth = mnPngDepth;
sal_uInt64 nScansize64 = ( ( static_cast< sal_uInt64 >( maOrigSize.Width() ) * mnPngDepth ) + 7 ) >> 3;
// valid color types are 0,2,3,4 & 6
switch ( mnColorType )
{
case 0 : // each pixel is a grayscale
{
switch ( mnPngDepth )
{
case 2 : // 2bit target not available -> use four bits
mnTargetDepth = 4; // we have to expand the bitmap
mbGrayScale = sal_True;
break;
case 16 :
mnTargetDepth = 8; // we have to reduce the bitmap
// fall through
case 1 :
case 4 :
case 8 :
mbGrayScale = sal_True;
break;
default :
return sal_False;
}
}
break;
case 2 : // each pixel is an RGB triple
{
mbRGBTriple = sal_True;
nScansize64 *= 3;
switch ( mnPngDepth )
{
case 16 : // we have to reduce the bitmap
case 8 :
mnTargetDepth = 24;
break;
default :
return sal_False;
}
}
break;
case 3 : // each pixel is a palette index
{
switch ( mnPngDepth )
{
case 2 :
mnTargetDepth = 4; // we have to expand the bitmap
// fall through
case 1 :
case 4 :
case 8 :
mbPalette = sal_False;
break;
default :
return sal_False;
}
}
break;
case 4 : // each pixel is a grayscale sample followed by an alpha sample
{
nScansize64 *= 2;
mbAlphaChannel = sal_True;
switch ( mnPngDepth )
{
case 16 :
mnTargetDepth = 8; // we have to reduce the bitmap
case 8 :
mbGrayScale = sal_True;
break;
default :
return sal_False;
}
}
break;
case 6 : // each pixel is an RGB triple followed by an alpha sample
{
mbRGBTriple = sal_True;
nScansize64 *= 4;
mbAlphaChannel = sal_True;
switch (mnPngDepth )
{
case 16 : // we have to reduce the bitmap
case 8 :
mnTargetDepth = 24;
break;
default :
return sal_False;
}
}
break;
default :
return sal_False;
}
mnBPP = static_cast< sal_uInt32 >( nScansize64 / maOrigSize.Width() );
if ( !mnBPP )
mnBPP = 1;
nScansize64++; // each scanline includes one filterbyte
if ( nScansize64 > SAL_MAX_UINT32 )
return sal_False;
mnScansize = static_cast< sal_uInt32 >( nScansize64 );
// TODO: switch between both scanlines instead of copying
mpInflateInBuf = new (std::nothrow) sal_uInt8[ mnScansize ];
mpScanCurrent = mpInflateInBuf;
mpScanPrior = new (std::nothrow) sal_uInt8[ mnScansize ];
if ( !mpInflateInBuf || !mpScanPrior )
return sal_False;
// calculate target size from original size and the preview hint
if( rPreviewSizeHint.Width() || rPreviewSizeHint.Height() )
{
Size aPreviewSize( rPreviewSizeHint.Width(), rPreviewSizeHint.Height() );
maTargetSize = maOrigSize;
if( aPreviewSize.Width() == 0 ) {
aPreviewSize.setWidth( ( maOrigSize.Width()*aPreviewSize.Height() )/maOrigSize.Height() );
if( aPreviewSize.Width() <= 0 )
aPreviewSize.setWidth( 1 );
} else if( aPreviewSize.Height() == 0 ) {
aPreviewSize.setHeight( ( maOrigSize.Height()*aPreviewSize.Width() )/maOrigSize.Width() );
if( aPreviewSize.Height() <= 0 )
aPreviewSize.setHeight( 1 );
}
if( aPreviewSize.Width() < maOrigSize.Width() && aPreviewSize.Height() < maOrigSize.Height() ) {
OSL_TRACE("preview size %dx%d", aPreviewSize.Width(), aPreviewSize.Height() );
for( int i = 1; i < 5; ++i )
{
if( (maTargetSize.Width() >> i) < aPreviewSize.Width() )
break;
if( (maTargetSize.Height() >> i) < aPreviewSize.Height() )
break;
mnPreviewShift = i;
}
mnPreviewMask = (1 << mnPreviewShift) - 1;
}
}
maTargetSize.Width() = (maOrigSize.Width() + mnPreviewMask) >> mnPreviewShift;
maTargetSize.Height() = (maOrigSize.Height() + mnPreviewMask) >> mnPreviewShift;
mpBmp = new Bitmap( maTargetSize, mnTargetDepth );
mpAcc = mpBmp->AcquireWriteAccess();
if( !mpAcc )
return sal_False;
mpBmp->SetSourceSizePixel( maOrigSize );
if ( mbAlphaChannel )
{
mpAlphaMask = new AlphaMask( maTargetSize );
mpAlphaMask->Erase( 128 );
mpMaskAcc = mpAlphaMask->AcquireWriteAccess();
if( !mpMaskAcc )
return sal_False;
}
if ( mbGrayScale )
ImplGetGrayPalette( mnPngDepth );
ImplPreparePass();
return sal_True;
}
// ------------------------------------------------------------------------
void PNGReaderImpl::ImplGetGrayPalette( sal_uInt16 nBitDepth )
{
if( nBitDepth > 8 )
nBitDepth = 8;
sal_uInt16 nPaletteEntryCount = 1 << nBitDepth;
sal_uInt32 nAdd = nBitDepth ? 256 / (nPaletteEntryCount - 1) : 0;
// no bitdepth==2 available
// but bitdepth==4 with two unused bits is close enough
if( nBitDepth == 2 )
nPaletteEntryCount = 16;
mpAcc->SetPaletteEntryCount( nPaletteEntryCount );
for ( sal_uInt32 i = 0, nStart = 0; nStart < 256; i++, nStart += nAdd )
mpAcc->SetPaletteColor( (sal_uInt16)i, BitmapColor( mpColorTable[ nStart ],
mpColorTable[ nStart ], mpColorTable[ nStart ] ) );
}
// ------------------------------------------------------------------------
sal_Bool PNGReaderImpl::ImplReadPalette()
{
sal_uInt16 nCount = static_cast<sal_uInt16>( mnChunkLen / 3 );
if ( ( ( mnChunkLen % 3 ) == 0 ) && ( ( 0 < nCount ) && ( nCount <= 256 ) ) && mpAcc )
{
mbPalette = sal_True;
mpAcc->SetPaletteEntryCount( (sal_uInt16) nCount );
for ( sal_uInt16 i = 0; i < nCount; i++ )
{
sal_uInt8 nRed = mpColorTable[ *maDataIter++ ];
sal_uInt8 nGreen = mpColorTable[ *maDataIter++ ];
sal_uInt8 nBlue = mpColorTable[ *maDataIter++ ];
mpAcc->SetPaletteColor( i, Color( nRed, nGreen, nBlue ) );
}
}
else
mbStatus = sal_False;
return mbStatus;
}
// ------------------------------------------------------------------------
sal_Bool PNGReaderImpl::ImplReadTransparent()
{
bool bNeedAlpha = false;
if ( mpTransTab == NULL )
{
switch ( mnColorType )
{
case 0 :
{
if ( mnChunkLen == 2 )
{
mpTransTab = new sal_uInt8[ 256 ];
rtl_fillMemory( mpTransTab, 256, 0xff );
// color type 0 and 4 is always greyscale,
// so the return value can be used as index
sal_uInt8 nIndex = ImplScaleColor();
mpTransTab[ nIndex ] = 0;
mbTransparent = true;
}
}
break;
case 2 :
{
if ( mnChunkLen == 6 )
{
mnTransRed = ImplScaleColor();
mnTransGreen = ImplScaleColor();
mnTransBlue = ImplScaleColor();
mbTransparent = true;
}
}
break;
case 3 :
{
if ( mnChunkLen <= 256 )
{
mpTransTab = new sal_uInt8 [ 256 ];
rtl_fillMemory( mpTransTab, 256, 0xff );
rtl_copyMemory( mpTransTab, &(*maDataIter), mnChunkLen );
maDataIter += mnChunkLen;
mbTransparent = true;
// need alpha transparency if not on/off masking
for( int i = 0; i < mnChunkLen; ++i )
bNeedAlpha |= (mpTransTab[i]!=0x00) && (mpTransTab[i]!=0xFF);
}
}
break;
}
}
if( mbTransparent && !mbAlphaChannel && !mpMaskBmp )
{
if( bNeedAlpha)
{
mpAlphaMask = new AlphaMask( maTargetSize );
mpMaskAcc = mpAlphaMask->AcquireWriteAccess();
}
else
{
mpMaskBmp = new Bitmap( maTargetSize, 1 );
mpMaskAcc = mpMaskBmp->AcquireWriteAccess();
}
mbTransparent = (mpMaskAcc != NULL);
if( !mbTransparent )
return sal_False;
mcOpaqueColor = BitmapColor( 0x00 );
mcTranspColor = BitmapColor( 0xFF );
mpMaskAcc->Erase( 0x00 );
}
return sal_True;
}
// ------------------------------------------------------------------------
void PNGReaderImpl::ImplGetGamma()
{
if( mnChunkLen < 4 )
return;
sal_uInt32 nGammaValue = ImplReadsal_uInt32();
double fGamma = ( ( VIEWING_GAMMA / DISPLAY_GAMMA ) * ( (double)nGammaValue / 100000 ) );
double fInvGamma = ( fGamma <= 0.0 || fGamma > 10.0 ) ? 1.0 : ( 1.0 / fGamma );
if ( fInvGamma != 1.0 )
{
mbGamma = sal_True;
if ( mpColorTable == mpDefaultColorTable )
mpColorTable = new sal_uInt8[ 256 ];
for ( sal_Int32 i = 0; i < 256; i++ )
mpColorTable[ i ] = (sal_uInt8)(pow((double)i/255.0, fInvGamma) * 255.0 + 0.5);
if ( mbGrayScale )
ImplGetGrayPalette( mnPngDepth );
}
}
// ------------------------------------------------------------------------
void PNGReaderImpl::ImplGetBackground()
{
switch ( mnColorType )
{
case 3 :
{
if ( mnChunkLen == 1 )
{
sal_uInt16 nCol = *maDataIter++;
if ( nCol < mpAcc->GetPaletteEntryCount() )
{
mpAcc->Erase( mpAcc->GetPaletteColor( (sal_uInt8)nCol ) );
break;
}
}
}
break;
case 0 :
case 4 :
{
if ( mnChunkLen == 2 )
{
// the color type 0 and 4 is always greyscale,
// so the return value can be used as index
sal_uInt8 nIndex = ImplScaleColor();
mpAcc->Erase( mpAcc->GetPaletteColor( nIndex ) );
}
}
break;
case 2 :
case 6 :
{
if ( mnChunkLen == 6 )
{
sal_uInt8 nRed = ImplScaleColor();
sal_uInt8 nGreen = ImplScaleColor();
sal_uInt8 nBlue = ImplScaleColor();
mpAcc->Erase( Color( nRed, nGreen, nBlue ) );
}
}
break;
}
}
// ------------------------------------------------------------------------
// for color type 0 and 4 (greyscale) the return value is always index to the color
// 2 and 6 (RGB) the return value is always the 8 bit color component
sal_uInt8 PNGReaderImpl::ImplScaleColor()
{
sal_uInt32 nMask = ( ( 1 << mnPngDepth ) - 1 );
sal_uInt16 nCol = ( *maDataIter++ << 8 );
nCol += *maDataIter++ & (sal_uInt16)nMask;
if ( mnPngDepth > 8 ) // convert 16bit graphics to 8
nCol >>= 8;
return (sal_uInt8) nCol;
}
// ------------------------------------------------------------------------
// ImplReadIDAT reads as much image data as needed
void PNGReaderImpl::ImplReadIDAT()
{
if( mnChunkLen > 0 )
{
if ( mbzCodecInUse == sal_False )
{
mbzCodecInUse = sal_True;
mpZCodec->BeginCompression( ZCODEC_PNG_DEFAULT );
}
mpZCodec->SetBreak( mnChunkLen );
SvMemoryStream aIStrm( &(*maDataIter), mnChunkLen, STREAM_READ );
while ( ( mpZCodec->GetBreak() ) )
{
// get bytes needed to fill the current scanline
sal_Int32 nToRead = mnScansize - (mpScanCurrent - mpInflateInBuf);
sal_Int32 nRead = mpZCodec->ReadAsynchron( aIStrm, mpScanCurrent, nToRead );
if ( nRead < 0 )
{
mbStatus = sal_False;
break;
}
if ( nRead < nToRead )
{
mpScanCurrent += nRead; // more ZStream data in the next IDAT chunk
break;
}
else // this scanline is Finished
{
mpScanCurrent = mpInflateInBuf;
ImplApplyFilter();
ImplDrawScanline( mnXStart, mnXAdd );
mnYpos += mnYAdd;
}
if ( mnYpos >= (sal_uInt32)maOrigSize.Height() )
{
if( (mnPass < 7) && mnInterlaceType )
if( ImplPreparePass() )
continue;
mbIDAT = true;
break;
}
}
}
if( mbIDAT )
{
mpZCodec->EndCompression();
mbzCodecInUse = sal_False;
}
}
// ---------------------------------------------------------------------------------------------------
bool PNGReaderImpl::ImplPreparePass()
{
struct InterlaceParams{ int mnXStart, mnYStart, mnXAdd, mnYAdd; };
static const InterlaceParams aInterlaceParams[8] =
{
// non-interlaced
{ 0, 0, 1, 1 },
// Adam7-interlaced
{ 0, 0, 8, 8 }, // pass 1
{ 4, 0, 8, 8 }, // pass 2
{ 0, 4, 4, 8 }, // pass 3
{ 2, 0, 4, 4 }, // pass 4
{ 0, 2, 2, 4 }, // pass 5
{ 1, 0, 2, 2 }, // pass 6
{ 0, 1, 1, 2 } // pass 7
};
const InterlaceParams* pParam = &aInterlaceParams[ 0 ];
if( mnInterlaceType )
{
while( ++mnPass <= 7 )
{
pParam = &aInterlaceParams[ mnPass ];
// skip this pass if the original image is too small for it
if( (pParam->mnXStart < maOrigSize.Width())
&& (pParam->mnYStart < maOrigSize.Height()) )
break;
}
if( mnPass > 7 )
return false;
// skip the last passes if possible (for scaled down target images)
if( mnPreviewMask & (pParam->mnXStart | pParam->mnYStart) )
return false;
}
mnYpos = pParam->mnYStart;
mnXStart = pParam->mnXStart;
mnXAdd = pParam->mnXAdd;
mnYAdd = pParam->mnYAdd;
// in Interlace mode the size of scanline is not constant
// so first we calculate the number of entrys
long nScanWidth = (maOrigSize.Width() - mnXStart + mnXAdd - 1) / mnXAdd;
mnScansize = nScanWidth;
if( mbRGBTriple )
mnScansize = 3 * nScanWidth;
if( mbAlphaChannel )
mnScansize += nScanWidth;
// convert to width in bytes
mnScansize = ( mnScansize*mnPngDepth + 7 ) >> 3;
++mnScansize; // scan size also needs room for the filtertype byte
rtl_zeroMemory( mpScanPrior, mnScansize );
return true;
}
// ----------------------------------------------------------------------------
// ImplApplyFilter writes the complete Scanline (nY)
// in interlace mode the parameter nXStart and nXAdd are non-zero
void PNGReaderImpl::ImplApplyFilter()
{
OSL_ASSERT( mnScansize >= mnBPP + 1 );
const sal_uInt8* const pScanEnd = mpInflateInBuf + mnScansize;
sal_uInt8 nFilterType = *mpInflateInBuf; // the filter type may change each scanline
switch ( nFilterType )
{
default: // unknown Scanline Filter Type
case 0: // Filter Type "None"
// we let the pixels pass and display the data unfiltered
break;
case 1: // Scanline Filter Type "Sub"
{
sal_uInt8* p1 = mpInflateInBuf + 1;
const sal_uInt8* p2 = p1;
p1 += mnBPP;
// use left pixels
do
*p1 = static_cast<sal_uInt8>( *p1 + *(p2++) );
while( ++p1 < pScanEnd );
}
break;
case 2: // Scanline Filter Type "Up"
{
sal_uInt8* p1 = mpInflateInBuf + 1;
const sal_uInt8* p2 = mpScanPrior + 1;
// use pixels from prior line
while( p1 < pScanEnd )
{
*p1 = static_cast<sal_uInt8>( *p1 + *(p2++) );
++p1;
}
}
break;
case 3: // Scanline Filter Type "Average"
{
sal_uInt8* p1 = mpInflateInBuf + 1;
const sal_uInt8* p2 = mpScanPrior + 1;
const sal_uInt8* p3 = p1;
// use one pixel from prior line
for( int n = mnBPP; --n >= 0; ++p1, ++p2)
*p1 = static_cast<sal_uInt8>( *p1 + (*p2 >> 1) );
// predict by averaging the left and prior line pixels
while( p1 < pScanEnd )
{
*p1 = static_cast<sal_uInt8>( *p1 + ((*(p2++) + *(p3++)) >> 1) );
++p1;
}
}
break;
case 4: // Scanline Filter Type "PaethPredictor"
{
sal_uInt8* p1 = mpInflateInBuf + 1;
const sal_uInt8* p2 = mpScanPrior + 1;
const sal_uInt8* p3 = p1;
const sal_uInt8* p4 = p2;
// use one pixel from prior line
for( int n = mnBPP; --n >= 0; ++p1)
*p1 = static_cast<sal_uInt8>( *p1 + *(p2++) );
// predict by using the left and the prior line pixels
while( p1 < pScanEnd )
{
int na = *(p2++);
int nb = *(p3++);
int nc = *(p4++);
int npa = nb - (int)nc;
int npb = na - (int)nc;
int npc = npa + npb;
if( npa < 0 )
npa =-npa;
if( npb < 0 )
npb =-npb;
if( npc < 0 )
npc =-npc;
if( npa > npb )
na = nb, npa = npb;
if( npa > npc )
na = nc;
*p1 = static_cast<sal_uInt8>( *p1 + na );
++p1;
}
}
break;
}
rtl_copyMemory( mpScanPrior, mpInflateInBuf, mnScansize );
}
// ---------------------------------------------------------------------------------------------------
// ImplDrawScanlines draws the complete Scanline (nY) into the target bitmap
// In interlace mode the parameter nXStart and nXAdd append to the currently used pass
void PNGReaderImpl::ImplDrawScanline( sal_uInt32 nXStart, sal_uInt32 nXAdd )
{
// optimization for downscaling
if( mnYpos & mnPreviewMask )
return;
if( nXStart & mnPreviewMask )
return;
// convert nY to pixel units in the target image
// => TODO; also do this for nX here instead of in the ImplSet*Pixel() methods
const sal_uInt32 nY = mnYpos >> mnPreviewShift;
const sal_uInt8* pTmp = mpInflateInBuf + 1;
if ( mpAcc->HasPalette() ) // alphachannel is not allowed by pictures including palette entries
{
switch ( mpAcc->GetBitCount() )
{
case 1 :
{
if ( mbTransparent )
{
for ( sal_Int32 nX = nXStart, nShift = 0; nX < maOrigSize.Width(); nX += nXAdd )
{
sal_uInt8 nCol;
nShift = (nShift - 1) & 7;
if ( nShift == 0 )
nCol = *(pTmp++);
else
nCol = static_cast<sal_uInt8>( *pTmp >> nShift );
nCol &= 1;
ImplSetAlphaPixel( nY, nX, nCol, mpTransTab[ nCol ] );
}
}
else
{ // BMP_FORMAT_1BIT_MSB_PAL
for ( sal_Int32 nX = nXStart, nShift = 0; nX < maOrigSize.Width(); nX += nXAdd )
{
nShift = (nShift - 1) & 7;
sal_uInt8 nCol;
if ( nShift == 0 )
nCol = *(pTmp++);
else
nCol = static_cast<sal_uInt8>( *pTmp >> nShift );
nCol &= 1;
ImplSetPixel( nY, nX, nCol );
}
}
}
break;
case 4 :
{
if ( mbTransparent )
{
if ( mnPngDepth == 4 ) // check if source has a two bit pixel format
{
for ( sal_Int32 nX = nXStart, nXIndex = 0; nX < maOrigSize.Width(); nX += nXAdd, ++nXIndex )
{
if( nXIndex & 1 )
{
ImplSetAlphaPixel( nY, nX, *pTmp & 0x0f, mpTransTab[ *pTmp & 0x0f ] );
pTmp++;
}
else
{
ImplSetAlphaPixel( nY, nX, ( *pTmp >> 4 ) & 0x0f, mpTransTab[ *pTmp >> 4 ] );
}
}
}
else // if ( mnPngDepth == 2 )
{
for ( sal_Int32 nX = nXStart, nXIndex = 0; nX < maOrigSize.Width(); nX += nXAdd, nXIndex++ )
{
sal_uInt8 nCol;
switch( nXIndex & 3 )
{
case 0 :
nCol = *pTmp >> 6;
break;
case 1 :
nCol = ( *pTmp >> 4 ) & 0x03 ;
break;
case 2 :
nCol = ( *pTmp >> 2 ) & 0x03;
break;
case 3 :
nCol = ( *pTmp++ ) & 0x03;
break;
default: // get rid of nCol uninitialized warning
nCol = 0;
break;
}
ImplSetAlphaPixel( nY, nX, nCol, mpTransTab[ nCol ] );
}
}
}
else
{
if ( mnPngDepth == 4 ) // maybe the source is a two bitmap graphic
{ // BMP_FORMAT_4BIT_LSN_PAL
for ( sal_Int32 nX = nXStart, nXIndex = 0; nX < maOrigSize.Width(); nX += nXAdd, nXIndex++ )
{
if( nXIndex & 1 )
ImplSetPixel( nY, nX, *pTmp++ & 0x0f );
else
ImplSetPixel( nY, nX, ( *pTmp >> 4 ) & 0x0f );
}
}
else // if ( mnPngDepth == 2 )
{
for ( sal_Int32 nX = nXStart, nXIndex = 0; nX < maOrigSize.Width(); nX += nXAdd, nXIndex++ )
{
switch( nXIndex & 3 )
{
case 0 :
ImplSetPixel( nY, nX, *pTmp >> 6 );
break;
case 1 :
ImplSetPixel( nY, nX, ( *pTmp >> 4 ) & 0x03 );
break;
case 2 :
ImplSetPixel( nY, nX, ( *pTmp >> 2 ) & 0x03 );
break;
case 3 :
ImplSetPixel( nY, nX, *pTmp++ & 0x03 );
break;
}
}
}
}
}
break;
case 8 :
{
if ( mbAlphaChannel )
{
if ( mnPngDepth == 8 ) // maybe the source is a 16 bit grayscale
{
for ( sal_Int32 nX = nXStart; nX < maOrigSize.Width(); nX += nXAdd, pTmp += 2 )
ImplSetAlphaPixel( nY, nX, pTmp[ 0 ], pTmp[ 1 ] );
}
else
{
for ( sal_Int32 nX = nXStart; nX < maOrigSize.Width(); nX += nXAdd, pTmp += 4 )
ImplSetAlphaPixel( nY, nX, pTmp[ 0 ], pTmp[ 2 ] );
}
}
else if ( mbTransparent )
{
if ( mnPngDepth == 8 ) // maybe the source is a 16 bit grayscale
{
for ( sal_Int32 nX = nXStart; nX < maOrigSize.Width(); nX += nXAdd, pTmp++ )
ImplSetAlphaPixel( nY, nX, *pTmp, mpTransTab[ *pTmp ] );
}
else
{
for ( sal_Int32 nX = nXStart; nX < maOrigSize.Width(); nX += nXAdd, pTmp += 2 )
ImplSetAlphaPixel( nY, nX, *pTmp, mpTransTab[ *pTmp ] );
}
}
else // neither alpha nor transparency
{
if ( mnPngDepth == 8 ) // maybe the source is a 16 bit grayscale
{
if( nXAdd == 1 && mnPreviewShift == 0 ) // copy raw line data if possible
{
int nLineBytes = maOrigSize.Width();
mpAcc->CopyScanline( nY, pTmp, BMP_FORMAT_8BIT_PAL, nLineBytes );
pTmp += nLineBytes;
}
else
{
for ( sal_Int32 nX = nXStart; nX < maOrigSize.Width(); nX += nXAdd )
ImplSetPixel( nY, nX, *pTmp++ );
}
}
else
{
for ( sal_Int32 nX = nXStart; nX < maOrigSize.Width(); nX += nXAdd, pTmp += 2 )
ImplSetPixel( nY, nX, *pTmp );
}
}
}
break;
default :
mbStatus = sal_False;
break;
}
}
else // no palette => truecolor
{
if( mbAlphaChannel ) // has RGB + alpha
{ // BMP_FORMAT_32BIT_TC_RGBA
if ( mnPngDepth == 8 ) // maybe the source has 16 bit per sample
{
if ( mpColorTable != mpDefaultColorTable )
{
for ( sal_Int32 nX = nXStart; nX < maOrigSize.Width(); nX += nXAdd, pTmp += 4 )
ImplSetAlphaPixel( nY, nX, BitmapColor( mpColorTable[ pTmp[ 0 ] ],
mpColorTable[ pTmp[ 1 ] ],
mpColorTable[ pTmp[ 2 ] ] ), pTmp[ 3 ] );
}
else
{
// if ( nXAdd == 1 && mnPreviewShift == 0 ) // copy raw line data if possible
// {
// int nLineBytes = 4 * maOrigSize.Width();
// mpAcc->CopyScanline( nY, pTmp, BMP_FORMAT_32BIT_TC_RGBA, nLineBytes );
// pTmp += nLineBytes;
// }
// else
{
for ( sal_Int32 nX = nXStart; nX < maOrigSize.Width(); nX += nXAdd, pTmp += 4 )
ImplSetAlphaPixel( nY, nX, BitmapColor( pTmp[0], pTmp[1], pTmp[2] ), pTmp[3] );
}
}
}
else
{ // BMP_FORMAT_64BIT_TC_RGBA
for ( sal_Int32 nX = nXStart; nX < maOrigSize.Width(); nX += nXAdd, pTmp += 8 )
ImplSetAlphaPixel( nY, nX, BitmapColor( mpColorTable[ pTmp[ 0 ] ],
mpColorTable[ pTmp[ 2 ] ],
mpColorTable[ pTmp[ 4 ] ] ), pTmp[6] );
}
}
else if( mbTransparent ) // has RGB + transparency
{ // BMP_FORMAT_24BIT_TC_RGB
if ( mnPngDepth == 8 ) // maybe the source has 16 bit per sample
{
for ( sal_Int32 nX = nXStart; nX < maOrigSize.Width(); nX += nXAdd, pTmp += 3 )
{
sal_uInt8 nRed = pTmp[ 0 ];
sal_uInt8 nGreen = pTmp[ 1 ];
sal_uInt8 nBlue = pTmp[ 2 ];
sal_Bool bTransparent = ( ( nRed == mnTransRed )
&& ( nGreen == mnTransGreen )
&& ( nBlue == mnTransBlue ) );
ImplSetTranspPixel( nY, nX, BitmapColor( mpColorTable[ nRed ],
mpColorTable[ nGreen ],
mpColorTable[ nBlue ] ), bTransparent );
}
}
else
{ // BMP_FORMAT_48BIT_TC_RGB
for ( sal_Int32 nX = nXStart; nX < maOrigSize.Width(); nX += nXAdd, pTmp += 6 )
{
sal_uInt8 nRed = pTmp[ 0 ];
sal_uInt8 nGreen = pTmp[ 2 ];
sal_uInt8 nBlue = pTmp[ 4 ];
sal_Bool bTransparent = ( ( nRed == mnTransRed )
&& ( nGreen == mnTransGreen )
&& ( nBlue == mnTransBlue ) );
ImplSetTranspPixel( nY, nX, BitmapColor( mpColorTable[ nRed ],
mpColorTable[ nGreen ],
mpColorTable[ nBlue ] ), bTransparent );
}
}
}
else // has RGB but neither alpha nor transparency
{ // BMP_FORMAT_24BIT_TC_RGB
if ( mnPngDepth == 8 ) // maybe the source has 16 bit per sample
{
if ( mpColorTable != mpDefaultColorTable )
{
for ( sal_Int32 nX = nXStart; nX < maOrigSize.Width(); nX += nXAdd, pTmp += 3 )
ImplSetPixel( nY, nX, BitmapColor( mpColorTable[ pTmp[ 0 ] ],
mpColorTable[ pTmp[ 1 ] ],
mpColorTable[ pTmp[ 2 ] ] ) );
}
else
{
if( nXAdd == 1 && mnPreviewShift == 0 ) // copy raw line data if possible
{
int nLineBytes = maOrigSize.Width() * 3;
mpAcc->CopyScanline( nY, pTmp, BMP_FORMAT_24BIT_TC_RGB, nLineBytes );
pTmp += nLineBytes;
}
else
{
for ( sal_Int32 nX = nXStart; nX < maOrigSize.Width(); nX += nXAdd, pTmp += 3 )
ImplSetPixel( nY, nX, BitmapColor( pTmp[0], pTmp[1], pTmp[2] ) );
}
}
}
else
{ // BMP_FORMAT_48BIT_TC_RGB
for ( sal_Int32 nX = nXStart; nX < maOrigSize.Width(); nX += nXAdd, pTmp += 6 )
ImplSetPixel( nY, nX, BitmapColor( mpColorTable[ pTmp[ 0 ] ],
mpColorTable[ pTmp[ 2 ] ],
mpColorTable[ pTmp[ 4 ] ] ) );
}
}
}
}
// ------------------------------------------------------------------------
void PNGReaderImpl::ImplSetPixel( sal_uInt32 nY, sal_uInt32 nX, const BitmapColor& rBitmapColor )
{
// TODO: get preview mode checks out of inner loop
if( nX & mnPreviewMask )
return;
nX >>= mnPreviewShift;
mpAcc->SetPixel( nY, nX, rBitmapColor );
}
// ------------------------------------------------------------------------
void PNGReaderImpl::ImplSetPixel( sal_uInt32 nY, sal_uInt32 nX, sal_uInt8 nPalIndex )
{
// TODO: get preview mode checks out of inner loop
if( nX & mnPreviewMask )
return;
nX >>= mnPreviewShift;
mpAcc->SetPixel( nY, nX, nPalIndex );
}
// ------------------------------------------------------------------------
void PNGReaderImpl::ImplSetTranspPixel( sal_uInt32 nY, sal_uInt32 nX, const BitmapColor& rBitmapColor, sal_Bool bTrans )
{
// TODO: get preview mode checks out of inner loop
if( nX & mnPreviewMask )
return;
nX >>= mnPreviewShift;
mpAcc->SetPixel( nY, nX, rBitmapColor );
if ( bTrans )
mpMaskAcc->SetPixel( nY, nX, mcTranspColor );
else
mpMaskAcc->SetPixel( nY, nX, mcOpaqueColor );
}
// ------------------------------------------------------------------------
void PNGReaderImpl::ImplSetAlphaPixel( sal_uInt32 nY, sal_uInt32 nX,
sal_uInt8 nPalIndex, sal_uInt8 nAlpha )
{
// TODO: get preview mode checks out of inner loop
if( nX & mnPreviewMask )
return;
nX >>= mnPreviewShift;
mpAcc->SetPixel( nY, nX, nPalIndex );
mpMaskAcc->SetPixel( nY, nX, ~nAlpha );
}
// ------------------------------------------------------------------------
void PNGReaderImpl::ImplSetAlphaPixel( sal_uInt32 nY, sal_uInt32 nX,
const BitmapColor& rBitmapColor, sal_uInt8 nAlpha )
{
// TODO: get preview mode checks out of inner loop
if( nX & mnPreviewMask )
return;
nX >>= mnPreviewShift;
mpAcc->SetPixel( nY, nX, rBitmapColor );
mpMaskAcc->SetPixel( nY, nX, ~nAlpha );
}
// ------------------------------------------------------------------------
sal_uInt32 PNGReaderImpl::ImplReadsal_uInt32()
{
sal_uInt32 nRet;
nRet = *maDataIter++;
nRet <<= 8;
nRet |= *maDataIter++;
nRet <<= 8;
nRet |= *maDataIter++;
nRet <<= 8;
nRet |= *maDataIter++;
return nRet;
}
// ------------------------------------------------------------------------
// -------------
// - PNGReader -
// -------------
PNGReader::PNGReader( SvStream& rIStm ) :
mpImpl( new ::vcl::PNGReaderImpl( rIStm ) )
{
}
// ------------------------------------------------------------------------
PNGReader::~PNGReader()
{
delete mpImpl;
}
// ------------------------------------------------------------------------
BitmapEx PNGReader::Read( const Size& i_rPreviewSizeHint )
{
return mpImpl->GetBitmapEx( i_rPreviewSizeHint );
}
// ------------------------------------------------------------------------
const std::vector< vcl::PNGReader::ChunkData >& PNGReader::GetChunks() const
{
return mpImpl->GetAllChunks();
}
// ------------------------------------------------------------------------
void PNGReader::SetIgnoreGammaChunk( sal_Bool b )
{
mpImpl->SetIgnoreGammaChunk( b );
}
} // namespace vcl
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
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