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diff --git a/src/plugins/imageformats/gif/qgifhandler.cpp b/src/plugins/imageformats/gif/qgifhandler.cpp
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-/****************************************************************************
-**
-** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
-** All rights reserved.
-** Contact: Nokia Corporation (qt-info@nokia.com)
-**
-** This file is part of the plugins of the Qt Toolkit.
-**
-** $QT_BEGIN_LICENSE:LGPL$
-** No Commercial Usage
-** This file contains pre-release code and may not be distributed.
-** You may use this file in accordance with the terms and conditions
-** contained in the Technology Preview License Agreement accompanying
-** this package.
-**
-** GNU Lesser General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU Lesser
-** General Public License version 2.1 as published by the Free Software
-** Foundation and appearing in the file LICENSE.LGPL included in the
-** packaging of this file. Please review the following information to
-** ensure the GNU Lesser General Public License version 2.1 requirements
-** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
-**
-** In addition, as a special exception, Nokia gives you certain additional
-** rights. These rights are described in the Nokia Qt LGPL Exception
-** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
-**
-** If you have questions regarding the use of this file, please contact
-** Nokia at qt-info@nokia.com.
-**
-**
-**
-**
-**
-**
-**
-**
-** $QT_END_LICENSE$
-**
-** WARNING:
-** A separate license from Unisys may be required to use the gif
-** reader. See http://www.unisys.com/about__unisys/lzw/
-** for information from Unisys
-**
-****************************************************************************/
-
-#include "qgifhandler.h"
-
-#include <qimage.h>
-#include <qiodevice.h>
-#include <qvariant.h>
-
-QT_BEGIN_NAMESPACE
-
-#define Q_TRANSPARENT 0x00ffffff
-
-// avoid going through QImage::scanLine() which calls detach
-#define FAST_SCAN_LINE(bits, bpl, y) (bits + (y) * bpl)
-
-
-/*
- Incremental image decoder for GIF image format.
-
- This subclass of QImageFormat decodes GIF format images,
- including animated GIFs. Internally in
-*/
-
-class QGIFFormat {
-public:
- QGIFFormat();
- ~QGIFFormat();
-
- int decode(QImage *image, const uchar* buffer, int length,
- int *nextFrameDelay, int *loopCount);
- static void scan(QIODevice *device, QVector<QSize> *imageSizes, int *loopCount);
-
- bool newFrame;
- bool partialNewFrame;
-
-private:
- void fillRect(QImage *image, int x, int y, int w, int h, QRgb col);
- inline QRgb color(uchar index) const;
-
- // GIF specific stuff
- QRgb* globalcmap;
- QRgb* localcmap;
- QImage backingstore;
- unsigned char hold[16];
- bool gif89;
- int count;
- int ccount;
- int expectcount;
- enum State {
- Header,
- LogicalScreenDescriptor,
- GlobalColorMap,
- LocalColorMap,
- Introducer,
- ImageDescriptor,
- TableImageLZWSize,
- ImageDataBlockSize,
- ImageDataBlock,
- ExtensionLabel,
- GraphicControlExtension,
- ApplicationExtension,
- NetscapeExtensionBlockSize,
- NetscapeExtensionBlock,
- SkipBlockSize,
- SkipBlock,
- Done,
- Error
- } state;
- int gncols;
- int lncols;
- int ncols;
- int lzwsize;
- bool lcmap;
- int swidth, sheight;
- int width, height;
- int left, top, right, bottom;
- enum Disposal { NoDisposal, DoNotChange, RestoreBackground, RestoreImage };
- Disposal disposal;
- bool disposed;
- int trans_index;
- bool gcmap;
- int bgcol;
- int interlace;
- int accum;
- int bitcount;
-
- enum { max_lzw_bits=12 }; // (poor-compiler's static const int)
-
- int code_size, clear_code, end_code, max_code_size, max_code;
- int firstcode, oldcode, incode;
- short* table[2];
- short* stack;
- short *sp;
- bool needfirst;
- int x, y;
- int frame;
- bool out_of_bounds;
- bool digress;
- void nextY(unsigned char *bits, int bpl);
- void disposePrevious(QImage *image);
-};
-
-/*!
- Constructs a QGIFFormat.
-*/
-QGIFFormat::QGIFFormat()
-{
- globalcmap = 0;
- localcmap = 0;
- lncols = 0;
- gncols = 0;
- disposal = NoDisposal;
- out_of_bounds = false;
- disposed = true;
- frame = -1;
- state = Header;
- count = 0;
- lcmap = false;
- newFrame = false;
- partialNewFrame = false;
- table[0] = 0;
- table[1] = 0;
- stack = 0;
-}
-
-/*!
- Destroys a QGIFFormat.
-*/
-QGIFFormat::~QGIFFormat()
-{
- if (globalcmap) delete[] globalcmap;
- if (localcmap) delete[] localcmap;
- delete [] stack;
-}
-
-void QGIFFormat::disposePrevious(QImage *image)
-{
- if (out_of_bounds) {
- // flush anything that survived
- // ### Changed: QRect(0, 0, swidth, sheight)
- }
-
- // Handle disposal of previous image before processing next one
-
- if (disposed) return;
-
- int l = qMin(swidth-1,left);
- int r = qMin(swidth-1,right);
- int t = qMin(sheight-1,top);
- int b = qMin(sheight-1,bottom);
-
- switch (disposal) {
- case NoDisposal:
- break;
- case DoNotChange:
- break;
- case RestoreBackground:
- if (trans_index>=0) {
- // Easy: we use the transparent color
- fillRect(image, l, t, r-l+1, b-t+1, Q_TRANSPARENT);
- } else if (bgcol>=0) {
- // Easy: we use the bgcol given
- fillRect(image, l, t, r-l+1, b-t+1, color(bgcol));
- } else {
- // Impossible: We don't know of a bgcol - use pixel 0
- QRgb *bits = (QRgb*)image->bits();
- fillRect(image, l, t, r-l+1, b-t+1, bits[0]);
- }
- // ### Changed: QRect(l, t, r-l+1, b-t+1)
- break;
- case RestoreImage: {
- if (frame >= 0) {
- for (int ln=t; ln<=b; ln++) {
- memcpy(image->scanLine(ln)+l,
- backingstore.scanLine(ln-t),
- (r-l+1)*sizeof(QRgb));
- }
- // ### Changed: QRect(l, t, r-l+1, b-t+1)
- }
- }
- }
- disposal = NoDisposal; // Until an extension says otherwise.
-
- disposed = true;
-}
-
-/*!
- This function decodes some data into image changes.
-
- Returns the number of bytes consumed.
-*/
-int QGIFFormat::decode(QImage *image, const uchar *buffer, int length,
- int *nextFrameDelay, int *loopCount)
-{
- // We are required to state that
- // "The Graphics Interchange Format(c) is the Copyright property of
- // CompuServe Incorporated. GIF(sm) is a Service Mark property of
- // CompuServe Incorporated."
-
- if (!stack) {
- stack = new short[(1 << max_lzw_bits) * 4];
- table[0] = &stack[(1 << max_lzw_bits) * 2];
- table[1] = &stack[(1 << max_lzw_bits) * 3];
- }
-
- image->detach();
- int bpl = image->bytesPerLine();
- unsigned char *bits = image->bits();
-
-#define LM(l, m) (((m)<<8)|l)
- digress = false;
- const int initial = length;
- while (!digress && length) {
- length--;
- unsigned char ch=*buffer++;
- switch (state) {
- case Header:
- hold[count++]=ch;
- if (count==6) {
- // Header
- gif89=(hold[3]!='8' || hold[4]!='7');
- state=LogicalScreenDescriptor;
- count=0;
- }
- break;
- case LogicalScreenDescriptor:
- hold[count++]=ch;
- if (count==7) {
- // Logical Screen Descriptor
- swidth=LM(hold[0], hold[1]);
- sheight=LM(hold[2], hold[3]);
- gcmap=!!(hold[4]&0x80);
- //UNUSED: bpchan=(((hold[4]&0x70)>>3)+1);
- //UNUSED: gcmsortflag=!!(hold[4]&0x08);
- gncols=2<<(hold[4]&0x7);
- bgcol=(gcmap) ? hold[5] : -1;
- //aspect=hold[6] ? double(hold[6]+15)/64.0 : 1.0;
-
- trans_index = -1;
- count=0;
- ncols=gncols;
- if (gcmap) {
- ccount=0;
- state=GlobalColorMap;
- globalcmap = new QRgb[gncols+1]; // +1 for trans_index
- globalcmap[gncols] = Q_TRANSPARENT;
- } else {
- state=Introducer;
- }
- }
- break;
- case GlobalColorMap: case LocalColorMap:
- hold[count++]=ch;
- if (count==3) {
- QRgb rgb = qRgb(hold[0], hold[1], hold[2]);
- if (state == LocalColorMap) {
- if (ccount < lncols)
- localcmap[ccount] = rgb;
- } else {
- globalcmap[ccount] = rgb;
- }
- if (++ccount >= ncols) {
- if (state == LocalColorMap)
- state=TableImageLZWSize;
- else
- state=Introducer;
- }
- count=0;
- }
- break;
- case Introducer:
- hold[count++]=ch;
- switch (ch) {
- case ',':
- state=ImageDescriptor;
- break;
- case '!':
- state=ExtensionLabel;
- break;
- case ';':
- // ### Changed: QRect(0, 0, swidth, sheight)
- state=Done;
- break;
- default:
- digress=true;
- // Unexpected Introducer - ignore block
- state=Error;
- }
- break;
- case ImageDescriptor:
- hold[count++]=ch;
- if (count==10) {
- int newleft=LM(hold[1], hold[2]);
- int newtop=LM(hold[3], hold[4]);
- int newwidth=LM(hold[5], hold[6]);
- int newheight=LM(hold[7], hold[8]);
-
- // disbelieve ridiculous logical screen sizes,
- // unless the image frames are also large.
- if (swidth/10 > qMax(newwidth,200))
- swidth = -1;
- if (sheight/10 > qMax(newheight,200))
- sheight = -1;
-
- if (swidth <= 0)
- swidth = newleft + newwidth;
- if (sheight <= 0)
- sheight = newtop + newheight;
-
- QImage::Format format = trans_index >= 0 ? QImage::Format_ARGB32 : QImage::Format_RGB32;
- if (image->isNull()) {
- (*image) = QImage(swidth, sheight, format);
- bpl = image->bytesPerLine();
- bits = image->bits();
- memset(bits, 0, image->byteCount());
- }
-
- disposePrevious(image);
- disposed = false;
-
- left = newleft;
- top = newtop;
- width = newwidth;
- height = newheight;
-
- right=qMax(0, qMin(left+width, swidth)-1);
- bottom=qMax(0, qMin(top+height, sheight)-1);
- lcmap=!!(hold[9]&0x80);
- interlace=!!(hold[9]&0x40);
- //bool lcmsortflag=!!(hold[9]&0x20);
- lncols=lcmap ? (2<<(hold[9]&0x7)) : 0;
- if (lncols) {
- if (localcmap)
- delete [] localcmap;
- localcmap = new QRgb[lncols+1];
- localcmap[lncols] = Q_TRANSPARENT;
- ncols = lncols;
- } else {
- ncols = gncols;
- }
- frame++;
- if (frame == 0) {
- if (left || top || width<swidth || height<sheight) {
- // Not full-size image - erase with bg or transparent
- if (trans_index >= 0) {
- fillRect(image, 0, 0, swidth, sheight, color(trans_index));
- // ### Changed: QRect(0, 0, swidth, sheight)
- } else if (bgcol>=0) {
- fillRect(image, 0, 0, swidth, sheight, color(bgcol));
- // ### Changed: QRect(0, 0, swidth, sheight)
- }
- }
- }
-
- if (disposal == RestoreImage) {
- int l = qMin(swidth-1,left);
- int r = qMin(swidth-1,right);
- int t = qMin(sheight-1,top);
- int b = qMin(sheight-1,bottom);
- int w = r-l+1;
- int h = b-t+1;
-
- if (backingstore.width() < w
- || backingstore.height() < h) {
- // We just use the backing store as a byte array
- backingstore = QImage(qMax(backingstore.width(), w),
- qMax(backingstore.height(), h),
- QImage::Format_RGB32);
- memset(bits, 0, image->byteCount());
- }
- const int dest_bpl = backingstore.bytesPerLine();
- unsigned char *dest_data = backingstore.bits();
- for (int ln=0; ln<h; ln++) {
- memcpy(FAST_SCAN_LINE(dest_data, dest_bpl, ln),
- FAST_SCAN_LINE(bits, bpl, t+ln) + l, w*sizeof(QRgb));
- }
- }
-
- count=0;
- if (lcmap) {
- ccount=0;
- state=LocalColorMap;
- } else {
- state=TableImageLZWSize;
- }
- x = left;
- y = top;
- accum = 0;
- bitcount = 0;
- sp = stack;
- firstcode = oldcode = 0;
- needfirst = true;
- out_of_bounds = left>=swidth || y>=sheight;
- }
- break;
- case TableImageLZWSize: {
- lzwsize=ch;
- if (lzwsize > max_lzw_bits) {
- state=Error;
- } else {
- code_size=lzwsize+1;
- clear_code=1<<lzwsize;
- end_code=clear_code+1;
- max_code_size=2*clear_code;
- max_code=clear_code+2;
- int i;
- for (i=0; i<clear_code; i++) {
- table[0][i]=0;
- table[1][i]=i;
- }
- state=ImageDataBlockSize;
- }
- count=0;
- break;
- } case ImageDataBlockSize:
- expectcount=ch;
- if (expectcount) {
- state=ImageDataBlock;
- } else {
- state=Introducer;
- digress = true;
- newFrame = true;
- }
- break;
- case ImageDataBlock:
- count++;
- accum|=(ch<<bitcount);
- bitcount+=8;
- while (bitcount>=code_size && state==ImageDataBlock) {
- int code=accum&((1<<code_size)-1);
- bitcount-=code_size;
- accum>>=code_size;
-
- if (code==clear_code) {
- if (!needfirst) {
- code_size=lzwsize+1;
- max_code_size=2*clear_code;
- max_code=clear_code+2;
- }
- needfirst=true;
- } else if (code==end_code) {
- bitcount = -32768;
- // Left the block end arrive
- } else {
- if (needfirst) {
- firstcode=oldcode=code;
- if (!out_of_bounds && image->height() > y && firstcode!=trans_index)
- ((QRgb*)FAST_SCAN_LINE(bits, bpl, y))[x] = color(firstcode);
- x++;
- if (x>=swidth) out_of_bounds = true;
- needfirst=false;
- if (x>=left+width) {
- x=left;
- out_of_bounds = left>=swidth || y>=sheight;
- nextY(bits, bpl);
- }
- } else {
- incode=code;
- if (code>=max_code) {
- *sp++=firstcode;
- code=oldcode;
- }
- while (code>=clear_code+2) {
- *sp++=table[1][code];
- if (code==table[0][code]) {
- state=Error;
- break;
- }
- if (sp-stack>=(1<<(max_lzw_bits))*2) {
- state=Error;
- break;
- }
- code=table[0][code];
- }
- *sp++=firstcode=table[1][code];
- code=max_code;
- if (code<(1<<max_lzw_bits)) {
- table[0][code]=oldcode;
- table[1][code]=firstcode;
- max_code++;
- if ((max_code>=max_code_size)
- && (max_code_size<(1<<max_lzw_bits)))
- {
- max_code_size*=2;
- code_size++;
- }
- }
- oldcode=incode;
- const int h = image->height();
- const QRgb *map = lcmap ? localcmap : globalcmap;
- QRgb *line = 0;
- if (!out_of_bounds && h > y)
- line = (QRgb*)FAST_SCAN_LINE(bits, bpl, y);
- while (sp>stack) {
- const uchar index = *(--sp);
- if (!out_of_bounds && h > y && index!=trans_index) {
- if (index > ncols)
- line[x] = Q_TRANSPARENT;
- else
- line[x] = map ? map[index] : 0;
- }
- x++;
- if (x>=swidth) out_of_bounds = true;
- if (x>=left+width) {
- x=left;
- out_of_bounds = left>=swidth || y>=sheight;
- nextY(bits, bpl);
- if (!out_of_bounds && h > y)
- line = (QRgb*)FAST_SCAN_LINE(bits, bpl, y);
- }
- }
- }
- }
- }
- partialNewFrame = true;
- if (count==expectcount) {
- count=0;
- state=ImageDataBlockSize;
- }
- break;
- case ExtensionLabel:
- switch (ch) {
- case 0xf9:
- state=GraphicControlExtension;
- break;
- case 0xff:
- state=ApplicationExtension;
- break;
-#if 0
- case 0xfe:
- state=CommentExtension;
- break;
- case 0x01:
- break;
-#endif
- default:
- state=SkipBlockSize;
- }
- count=0;
- break;
- case ApplicationExtension:
- if (count<11) hold[count]=ch;
- count++;
- if (count==hold[0]+1) {
- if (qstrncmp((char*)(hold+1), "NETSCAPE", 8)==0) {
- // Looping extension
- state=NetscapeExtensionBlockSize;
- } else {
- state=SkipBlockSize;
- }
- count=0;
- }
- break;
- case NetscapeExtensionBlockSize:
- expectcount=ch;
- count=0;
- if (expectcount) state=NetscapeExtensionBlock;
- else state=Introducer;
- break;
- case NetscapeExtensionBlock:
- if (count<3) hold[count]=ch;
- count++;
- if (count==expectcount) {
- *loopCount = hold[1]+hold[2]*256;
- state=SkipBlockSize; // Ignore further blocks
- }
- break;
- case GraphicControlExtension:
- if (count<5) hold[count]=ch;
- count++;
- if (count==hold[0]+1) {
- disposePrevious(image);
- disposal=Disposal((hold[1]>>2)&0x7);
- //UNUSED: waitforuser=!!((hold[1]>>1)&0x1);
- int delay=count>3 ? LM(hold[2], hold[3]) : 1;
- // IE and mozilla use a minimum delay of 10. With the minimum delay of 10
- // we are compatible to them and avoid huge loads on the app and xserver.
- *nextFrameDelay = (delay < 2 ? 10 : delay) * 10;
-
- bool havetrans=hold[1]&0x1;
- trans_index = havetrans ? hold[4] : -1;
-
- count=0;
- state=SkipBlockSize;
- }
- break;
- case SkipBlockSize:
- expectcount=ch;
- count=0;
- if (expectcount) state=SkipBlock;
- else state=Introducer;
- break;
- case SkipBlock:
- count++;
- if (count==expectcount) state=SkipBlockSize;
- break;
- case Done:
- digress=true;
- /* Netscape ignores the junk, so we do too.
- length++; // Unget
- state=Error; // More calls to this is an error
- */
- break;
- case Error:
- return -1; // Called again after done.
- }
- }
- return initial-length;
-}
-
-/*!
- Scans through the data stream defined by \a device and returns the image
- sizes found in the stream in the \a imageSizes vector.
-*/
-void QGIFFormat::scan(QIODevice *device, QVector<QSize> *imageSizes, int *loopCount)
-{
- if (!device)
- return;
-
- qint64 oldPos = device->pos();
- if (!device->seek(0))
- return;
-
- int colorCount = 0;
- int localColorCount = 0;
- int globalColorCount = 0;
- int colorReadCount = 0;
- bool localColormap = false;
- bool globalColormap = false;
- int count = 0;
- int blockSize = 0;
- int imageWidth = 0;
- int imageHeight = 0;
- bool done = false;
- uchar hold[16];
- State state = Header;
-
- const int readBufferSize = 40960; // 40k read buffer
- QByteArray readBuffer(device->read(readBufferSize));
-
- if (readBuffer.isEmpty()) {
- device->seek(oldPos);
- return;
- }
-
- // This is a specialized version of the state machine from decode(),
- // which doesn't do any image decoding or mallocing, and has an
- // optimized way of skipping SkipBlocks, ImageDataBlocks and
- // Global/LocalColorMaps.
-
- while (!readBuffer.isEmpty()) {
- int length = readBuffer.size();
- const uchar *buffer = (const uchar *) readBuffer.constData();
- while (!done && length) {
- length--;
- uchar ch = *buffer++;
- switch (state) {
- case Header:
- hold[count++] = ch;
- if (count == 6) {
- state = LogicalScreenDescriptor;
- count = 0;
- }
- break;
- case LogicalScreenDescriptor:
- hold[count++] = ch;
- if (count == 7) {
- imageWidth = LM(hold[0], hold[1]);
- imageHeight = LM(hold[2], hold[3]);
- globalColormap = !!(hold[4] & 0x80);
- globalColorCount = 2 << (hold[4] & 0x7);
- count = 0;
- colorCount = globalColorCount;
- if (globalColormap) {
- int colorTableSize = 3 * globalColorCount;
- if (length >= colorTableSize) {
- // skip the global color table in one go
- length -= colorTableSize;
- buffer += colorTableSize;
- state = Introducer;
- } else {
- colorReadCount = 0;
- state = GlobalColorMap;
- }
- } else {
- state=Introducer;
- }
- }
- break;
- case GlobalColorMap:
- case LocalColorMap:
- hold[count++] = ch;
- if (count == 3) {
- if (++colorReadCount >= colorCount) {
- if (state == LocalColorMap)
- state = TableImageLZWSize;
- else
- state = Introducer;
- }
- count = 0;
- }
- break;
- case Introducer:
- hold[count++] = ch;
- switch (ch) {
- case 0x2c:
- state = ImageDescriptor;
- break;
- case 0x21:
- state = ExtensionLabel;
- break;
- case 0x3b:
- state = Done;
- break;
- default:
- done = true;
- state = Error;
- }
- break;
- case ImageDescriptor:
- hold[count++] = ch;
- if (count == 10) {
- int newLeft = LM(hold[1], hold[2]);
- int newTop = LM(hold[3], hold[4]);
- int newWidth = LM(hold[5], hold[6]);
- int newHeight = LM(hold[7], hold[8]);
-
- if (imageWidth/10 > qMax(newWidth,200))
- imageWidth = -1;
- if (imageHeight/10 > qMax(newHeight,200))
- imageHeight = -1;
-
- if (imageWidth <= 0)
- imageWidth = newLeft + newWidth;
- if (imageHeight <= 0)
- imageHeight = newTop + newHeight;
-
- *imageSizes << QSize(imageWidth, imageHeight);
-
- localColormap = !!(hold[9] & 0x80);
- localColorCount = localColormap ? (2 << (hold[9] & 0x7)) : 0;
- if (localColorCount)
- colorCount = localColorCount;
- else
- colorCount = globalColorCount;
-
- count = 0;
- if (localColormap) {
- int colorTableSize = 3 * localColorCount;
- if (length >= colorTableSize) {
- // skip the local color table in one go
- length -= colorTableSize;
- buffer += colorTableSize;
- state = TableImageLZWSize;
- } else {
- colorReadCount = 0;
- state = LocalColorMap;
- }
- } else {
- state = TableImageLZWSize;
- }
- }
- break;
- case TableImageLZWSize:
- if (ch > max_lzw_bits)
- state = Error;
- else
- state = ImageDataBlockSize;
- count = 0;
- break;
- case ImageDataBlockSize:
- blockSize = ch;
- if (blockSize) {
- if (length >= blockSize) {
- // we can skip the block in one go
- length -= blockSize;
- buffer += blockSize;
- count = 0;
- } else {
- state = ImageDataBlock;
- }
- } else {
- state = Introducer;
- }
- break;
- case ImageDataBlock:
- ++count;
- if (count == blockSize) {
- count = 0;
- state = ImageDataBlockSize;
- }
- break;
- case ExtensionLabel:
- switch (ch) {
- case 0xf9:
- state = GraphicControlExtension;
- break;
- case 0xff:
- state = ApplicationExtension;
- break;
- default:
- state = SkipBlockSize;
- }
- count = 0;
- break;
- case ApplicationExtension:
- if (count < 11)
- hold[count] = ch;
- ++count;
- if (count == hold[0] + 1) {
- if (qstrncmp((char*)(hold+1), "NETSCAPE", 8) == 0)
- state=NetscapeExtensionBlockSize;
- else
- state=SkipBlockSize;
- count = 0;
- }
- break;
- case GraphicControlExtension:
- if (count < 5)
- hold[count] = ch;
- ++count;
- if (count == hold[0] + 1) {
- count = 0;
- state = SkipBlockSize;
- }
- break;
- case NetscapeExtensionBlockSize:
- blockSize = ch;
- count = 0;
- if (blockSize)
- state = NetscapeExtensionBlock;
- else
- state = Introducer;
- break;
- case NetscapeExtensionBlock:
- if (count < 3)
- hold[count] = ch;
- count++;
- if (count == blockSize) {
- *loopCount = LM(hold[1], hold[2]);
- state = SkipBlockSize;
- }
- break;
- case SkipBlockSize:
- blockSize = ch;
- count = 0;
- if (blockSize) {
- if (length >= blockSize) {
- // we can skip the block in one go
- length -= blockSize;
- buffer += blockSize;
- } else {
- state = SkipBlock;
- }
- } else {
- state = Introducer;
- }
- break;
- case SkipBlock:
- ++count;
- if (count == blockSize)
- state = SkipBlockSize;
- break;
- case Done:
- done = true;
- break;
- case Error:
- device->seek(oldPos);
- return;
- }
- }
- readBuffer = device->read(readBufferSize);
- }
- device->seek(oldPos);
- return;
-}
-
-void QGIFFormat::fillRect(QImage *image, int col, int row, int w, int h, QRgb color)
-{
- if (w>0) {
- for (int j=0; j<h; j++) {
- QRgb *line = (QRgb*)image->scanLine(j+row);
- for (int i=0; i<w; i++)
- *(line+col+i) = color;
- }
- }
-}
-
-void QGIFFormat::nextY(unsigned char *bits, int bpl)
-{
- int my;
- switch (interlace) {
- case 0: // Non-interlaced
- // if (!out_of_bounds) {
- // ### Changed: QRect(left, y, right - left + 1, 1);
- // }
- y++;
- break;
- case 1: {
- int i;
- my = qMin(7, bottom-y);
- // Don't dup with transparency
- if (trans_index < 0) {
- for (i=1; i<=my; i++) {
- memcpy(FAST_SCAN_LINE(bits, bpl, y+i)+left*sizeof(QRgb), FAST_SCAN_LINE(bits, bpl, y)+left*sizeof(QRgb),
- (right-left+1)*sizeof(QRgb));
- }
- }
-
- // if (!out_of_bounds) {
- // ### Changed: QRect(left, y, right - left + 1, my + 1);
- // }
-// if (!out_of_bounds)
-// qDebug("consumer->changed(QRect(%d, %d, %d, %d))", left, y, right-left+1, my+1);
- y+=8;
- if (y>bottom) {
- interlace++; y=top+4;
- if (y > bottom) { // for really broken GIFs with bottom < 5
- interlace=2;
- y = top + 2;
- if (y > bottom) { // for really broken GIF with bottom < 3
- interlace = 0;
- y = top + 1;
- }
- }
- }
- } break;
- case 2: {
- int i;
- my = qMin(3, bottom-y);
- // Don't dup with transparency
- if (trans_index < 0) {
- for (i=1; i<=my; i++) {
- memcpy(FAST_SCAN_LINE(bits, bpl, y+i)+left*sizeof(QRgb), FAST_SCAN_LINE(bits, bpl, y)+left*sizeof(QRgb),
- (right-left+1)*sizeof(QRgb));
- }
- }
-
- // if (!out_of_bounds) {
- // ### Changed: QRect(left, y, right - left + 1, my + 1);
- // }
- y+=8;
- if (y>bottom) {
- interlace++; y=top+2;
- // handle broken GIF with bottom < 3
- if (y > bottom) {
- interlace = 3;
- y = top + 1;
- }
- }
- } break;
- case 3: {
- int i;
- my = qMin(1, bottom-y);
- // Don't dup with transparency
- if (trans_index < 0) {
- for (i=1; i<=my; i++) {
- memcpy(FAST_SCAN_LINE(bits, bpl, y+i)+left*sizeof(QRgb), FAST_SCAN_LINE(bits, bpl, y)+left*sizeof(QRgb),
- (right-left+1)*sizeof(QRgb));
- }
- }
- // if (!out_of_bounds) {
- // ### Changed: QRect(left, y, right - left + 1, my + 1);
- // }
- y+=4;
- if (y>bottom) { interlace++; y=top+1; }
- } break;
- case 4:
- // if (!out_of_bounds) {
- // ### Changed: QRect(left, y, right - left + 1, 1);
- // }
- y+=2;
- }
-
- // Consume bogus extra lines
- if (y >= sheight) out_of_bounds=true; //y=bottom;
-}
-
-inline QRgb QGIFFormat::color(uchar index) const
-{
- if (index == trans_index || index > ncols)
- return Q_TRANSPARENT;
-
- QRgb *map = lcmap ? localcmap : globalcmap;
- return map ? map[index] : 0;
-}
-
-//-------------------------------------------------------------------------
-//-------------------------------------------------------------------------
-//-------------------------------------------------------------------------
-
-QGifHandler::QGifHandler()
-{
- gifFormat = new QGIFFormat;
- nextDelay = 100;
- loopCnt = 1;
- frameNumber = -1;
- scanIsCached = false;
-}
-
-QGifHandler::~QGifHandler()
-{
- delete gifFormat;
-}
-
-// Does partial decode if necessary, just to see if an image is coming
-
-bool QGifHandler::imageIsComing() const
-{
- const int GifChunkSize = 4096;
-
- while (!gifFormat->partialNewFrame) {
- if (buffer.isEmpty()) {
- buffer += device()->read(GifChunkSize);
- if (buffer.isEmpty())
- break;
- }
-
- int decoded = gifFormat->decode(&lastImage, (const uchar *)buffer.constData(), buffer.size(),
- &nextDelay, &loopCnt);
- if (decoded == -1)
- break;
- buffer.remove(0, decoded);
- }
- return gifFormat->partialNewFrame;
-}
-
-bool QGifHandler::canRead() const
-{
- if (canRead(device()) || imageIsComing()) {
- setFormat("gif");
- return true;
- }
-
- return false;
-}
-
-bool QGifHandler::canRead(QIODevice *device)
-{
- if (!device) {
- qWarning("QGifHandler::canRead() called with no device");
- return false;
- }
-
- char head[6];
- if (device->peek(head, sizeof(head)) == sizeof(head))
- return qstrncmp(head, "GIF87a", 6) == 0
- || qstrncmp(head, "GIF89a", 6) == 0;
- return false;
-}
-
-bool QGifHandler::read(QImage *image)
-{
- const int GifChunkSize = 4096;
-
- while (!gifFormat->newFrame) {
- if (buffer.isEmpty()) {
- buffer += device()->read(GifChunkSize);
- if (buffer.isEmpty())
- break;
- }
-
- int decoded = gifFormat->decode(&lastImage, (const uchar *)buffer.constData(), buffer.size(),
- &nextDelay, &loopCnt);
- if (decoded == -1)
- break;
- buffer.remove(0, decoded);
- }
- if (gifFormat->newFrame || (gifFormat->partialNewFrame && device()->atEnd())) {
- *image = lastImage;
- ++frameNumber;
- gifFormat->newFrame = false;
- gifFormat->partialNewFrame = false;
- return true;
- }
-
- return false;
-}
-
-bool QGifHandler::write(const QImage &image)
-{
- Q_UNUSED(image);
- return false;
-}
-
-bool QGifHandler::supportsOption(ImageOption option) const
-{
- if (!device() || device()->isSequential())
- return option == Animation;
- else
- return option == Size
- || option == Animation;
-}
-
-QVariant QGifHandler::option(ImageOption option) const
-{
- if (option == Size) {
- if (!scanIsCached) {
- QGIFFormat::scan(device(), &imageSizes, &loopCnt);
- scanIsCached = true;
- }
- // before the first frame is read, or we have an empty data stream
- if (frameNumber == -1)
- return (imageSizes.count() > 0) ? QVariant(imageSizes.at(0)) : QVariant();
- // after the last frame has been read, the next size is undefined
- if (frameNumber >= imageSizes.count() - 1)
- return QVariant();
- // and the last case: the size of the next frame
- return imageSizes.at(frameNumber + 1);
- } else if (option == Animation) {
- return true;
- }
- return QVariant();
-}
-
-void QGifHandler::setOption(ImageOption option, const QVariant &value)
-{
- Q_UNUSED(option);
- Q_UNUSED(value);
-}
-
-int QGifHandler::nextImageDelay() const
-{
- return nextDelay;
-}
-
-int QGifHandler::imageCount() const
-{
- if (!scanIsCached) {
- QGIFFormat::scan(device(), &imageSizes, &loopCnt);
- scanIsCached = true;
- }
- return imageSizes.count();
-}
-
-int QGifHandler::loopCount() const
-{
- if (!scanIsCached) {
- QGIFFormat::scan(device(), &imageSizes, &loopCnt);
- scanIsCached = true;
- }
- return loopCnt-1; // In GIF, loop count is iteration count, so subtract one
-}
-
-int QGifHandler::currentImageNumber() const
-{
- return frameNumber;
-}
-
-QByteArray QGifHandler::name() const
-{
- return "gif";
-}
-
-QT_END_NAMESPACE
generated by cgit v0.12 at 2025-02-18 03:00:36 (GMT)