/****************************************************************************
**
** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
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** Contact: Nokia Corporation (qt-info@nokia.com)
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** This file is part of the plugins of the Qt Toolkit.
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** No Commercial Usage
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** contained in the Technology Preview License Agreement accompanying
** this package.
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** General Public License version 2.1 as published by the Free Software
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** packaging of this file. Please review the following information to
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** $QT_END_LICENSE$
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****************************************************************************/
#include "qjpeghandler_p.h"
#include <qimage.h>
#include <qvariant.h>
#include <qvector.h>
#include <qbuffer.h>
#include <stdio.h> // jpeglib needs this to be pre-included
#include <setjmp.h>
#ifdef FAR
#undef FAR
#endif
// including jpeglib.h seems to be a little messy
extern "C" {
// mingw includes rpcndr.h but does not define boolean
#if defined(Q_OS_WIN) && defined(Q_CC_GNU)
# if defined(__RPCNDR_H__) && !defined(boolean)
typedef unsigned char boolean;
# define HAVE_BOOLEAN
# endif
#endif
#define XMD_H // shut JPEGlib up
#if defined(Q_OS_UNIXWARE)
# define HAVE_BOOLEAN // libjpeg under Unixware seems to need this
#endif
#include <jpeglib.h>
#ifdef const
# undef const // remove crazy C hackery in jconfig.h
#endif
}
QT_BEGIN_NAMESPACE
struct my_error_mgr : public jpeg_error_mgr {
jmp_buf setjmp_buffer;
};
#if defined(Q_C_CALLBACKS)
extern "C" {
#endif
static void my_error_exit (j_common_ptr cinfo)
{
my_error_mgr* myerr = (my_error_mgr*) cinfo->err;
char buffer[JMSG_LENGTH_MAX];
(*cinfo->err->format_message)(cinfo, buffer);
qWarning("%s", buffer);
longjmp(myerr->setjmp_buffer, 1);
}
#if defined(Q_C_CALLBACKS)
}
#endif
static const int max_buf = 4096;
struct my_jpeg_source_mgr : public jpeg_source_mgr {
// Nothing dynamic - cannot rely on destruction over longjump
QIODevice *device;
JOCTET buffer[max_buf];
const QBuffer *memDevice;
public:
my_jpeg_source_mgr(QIODevice *device);
};
#if defined(Q_C_CALLBACKS)
extern "C" {
#endif
static void qt_init_source(j_decompress_ptr)
{
}
static boolean qt_fill_input_buffer(j_decompress_ptr cinfo)
{
my_jpeg_source_mgr* src = (my_jpeg_source_mgr*)cinfo->src;
if (src->memDevice) {
src->next_input_byte = (const JOCTET *)(src->memDevice->data().constData() + src->memDevice->pos());
src->bytes_in_buffer = (size_t)(src->memDevice->data().size() - src->memDevice->pos());
return true;
}
src->next_input_byte = src->buffer;
int num_read = src->device->read((char*)src->buffer, max_buf);
if (num_read <= 0) {
// Insert a fake EOI marker - as per jpeglib recommendation
src->buffer[0] = (JOCTET) 0xFF;
src->buffer[1] = (JOCTET) JPEG_EOI;
src->bytes_in_buffer = 2;
} else {
src->bytes_in_buffer = num_read;
}
#if defined(Q_OS_UNIXWARE)
return B_TRUE;
#else
return true;
#endif
}
static void qt_skip_input_data(j_decompress_ptr cinfo, long num_bytes)
{
my_jpeg_source_mgr* src = (my_jpeg_source_mgr*)cinfo->src;
// `dumb' implementation from jpeglib
/* Just a dumb implementation for now. Could use fseek() except
* it doesn't work on pipes. Not clear that being smart is worth
* any trouble anyway --- large skips are infrequent.
*/
if (num_bytes > 0) {
while (num_bytes > (long) src->bytes_in_buffer) { // Should not happen in case of memDevice
num_bytes -= (long) src->bytes_in_buffer;
(void) qt_fill_input_buffer(cinfo);
/* note we assume that qt_fill_input_buffer will never return false,
* so suspension need not be handled.
*/
}
src->next_input_byte += (size_t) num_bytes;
src->bytes_in_buffer -= (size_t) num_bytes;
}
}
static void qt_term_source(j_decompress_ptr cinfo)
{
my_jpeg_source_mgr* src = (my_jpeg_source_mgr*)cinfo->src;
if (!src->device->isSequential())
{
// read() isn't used for memDevice, so seek past everything that was used
if (src->memDevice)
src->device->seek(src->device->pos() + (src->memDevice->data().size() - src->memDevice->pos() - src->bytes_in_buffer));
else
src->device->seek(src->device->pos() - src->bytes_in_buffer);
}
}
#if defined(Q_C_CALLBACKS)
}
#endif
inline my_jpeg_source_mgr::my_jpeg_source_mgr(QIODevice *device)
{
jpeg_source_mgr::init_source = qt_init_source;
jpeg_source_mgr::fill_input_buffer = qt_fill_input_buffer;
jpeg_source_mgr::skip_input_data = qt_skip_input_data;
jpeg_source_mgr::resync_to_restart = jpeg_resync_to_restart;
jpeg_source_mgr::term_source = qt_term_source;
this->device = device;
memDevice = qobject_cast<QBuffer *>(device);
bytes_in_buffer = 0;
next_input_byte = buffer;
}
inline static bool read_jpeg_size(int &w, int &h, j_decompress_ptr cinfo)
{
(void) jpeg_calc_output_dimensions(cinfo);
w = cinfo->output_width;
h = cinfo->output_height;
return true;
}
#define HIGH_QUALITY_THRESHOLD 50
inline static bool read_jpeg_format(QImage::Format &format, j_decompress_ptr cinfo)
{
bool result = true;
switch (cinfo->output_components) {
case 1:
format = QImage::Format_Indexed8;
break;
case 3:
case 4:
format = QImage::Format_RGB32;
break;
default:
result = false;
break;
}
cinfo->output_scanline = cinfo->output_height;
return result;
}
static bool ensureValidImage(QImage *dest, struct jpeg_decompress_struct *info,
const QSize& size)
{
QImage::Format format;
switch (info->output_components) {
case 1:
format = QImage::Format_Indexed8;
break;
case 3:
case 4:
format = QImage::Format_RGB32;
break;
default:
return false; // unsupported format
}
if (dest->size() != size || dest->format() != format) {
*dest = QImage(size, format);
if (format == QImage::Format_Indexed8) {
dest->setColorCount(256);
for (int i = 0; i < 256; i++)
dest->setColor(i, qRgb(i,i,i));
}
}
return !dest->isNull();
}
static bool read_jpeg_image(QImage *outImage,
QSize scaledSize, QRect scaledClipRect,
QRect clipRect, int inQuality, j_decompress_ptr info, struct my_error_mgr* err )
{
if (!setjmp(err->setjmp_buffer)) {
// -1 means default quality.
int quality = inQuality;
if (quality < 0)
quality = 75;
// If possible, merge the scaledClipRect into either scaledSize
// or clipRect to avoid doing a separate scaled clipping pass.
// Best results are achieved by clipping before scaling, not after.
if (!scaledClipRect.isEmpty()) {
if (scaledSize.isEmpty() && clipRect.isEmpty()) {
// No clipping or scaling before final clip.
clipRect = scaledClipRect;
scaledClipRect = QRect();
} else if (scaledSize.isEmpty()) {
// Clipping, but no scaling: combine the clip regions.
scaledClipRect.translate(clipRect.topLeft());
clipRect = scaledClipRect.intersected(clipRect);
scaledClipRect = QRect();
} else if (clipRect.isEmpty()) {
// No clipping, but scaling: if we can map back to an
// integer pixel boundary, then clip before scaling.
if ((info->image_width % scaledSize.width()) == 0 &&
(info->image_height % scaledSize.height()) == 0) {
int x = scaledClipRect.x() * info->image_width /
scaledSize.width();
int y = scaledClipRect.y() * info->image_height /
scaledSize.height();
int width = (scaledClipRect.right() + 1) *
info->image_width / scaledSize.width() - x;
int height = (scaledClipRect.bottom() + 1) *
info->image_height / scaledSize.height() - y;
clipRect = QRect(x, y, width, height);
scaledSize = scaledClipRect.size();
scaledClipRect = QRect();
}
} else {
// Clipping and scaling: too difficult to figure out,
// and not a likely use case, so do it the long way.
}
}
// Determine the scale factor to pass to libjpeg for quick downscaling.
if (!scaledSize.isEmpty()) {
if (clipRect.isEmpty()) {
info->scale_denom =
qMin(info->image_width / scaledSize.width(),
info->image_height / scaledSize.height());
} else {
info->scale_denom =
qMin(clipRect.width() / scaledSize.width(),
clipRect.height() / scaledSize.height());
}
if (info->scale_denom < 2) {
info->scale_denom = 1;
} else if (info->scale_denom < 4) {
info->scale_denom = 2;
} else if (info->scale_denom < 8) {
info->scale_denom = 4;
} else {
info->scale_denom = 8;
}
info->scale_num = 1;
if (!clipRect.isEmpty()) {
// Correct the scale factor so that we clip accurately.
// It is recommended that the clip rectangle be aligned
// on an 8-pixel boundary for best performance.
while (info->scale_denom > 1 &&
((clipRect.x() % info->scale_denom) != 0 ||
(clipRect.y() % info->scale_denom) != 0 ||
(clipRect.width() % info->scale_denom) != 0 ||
(clipRect.height() % info->scale_denom) != 0)) {
info->scale_denom /= 2;
}
}
}
// If high quality not required, use fast decompression
if( quality < HIGH_QUALITY_THRESHOLD ) {
info->dct_method = JDCT_IFAST;
info->do_fancy_upsampling = FALSE;
}
(void) jpeg_calc_output_dimensions(info);
// Determine the clip region to extract.
QRect imageRect(0, 0, info->output_width, info->output_height);
QRect clip;
if (clipRect.isEmpty()) {
clip = imageRect;
} else if (info->scale_denom == info->scale_num) {
clip = clipRect.intersected(imageRect);
} else {
// The scale factor was corrected above to ensure that
// we don't miss pixels when we scale the clip rectangle.
clip = QRect(clipRect.x() / int(info->scale_denom),
clipRect.y() / int(info->scale_denom),
clipRect.width() / int(info->scale_denom),
clipRect.height() / int(info->scale_denom));
clip = clip.intersected(imageRect);
}
// Allocate memory for the clipped QImage.
if (!ensureValidImage(outImage, info, clip.size()))
longjmp(err->setjmp_buffer, 1);
// Avoid memcpy() overhead if grayscale with no clipping.
bool quickGray = (info->output_components == 1 &&
clip == imageRect);
if (!quickGray) {
// Ask the jpeg library to allocate a temporary row.
// The library will automatically delete it for us later.
// The libjpeg docs say we should do this before calling
// jpeg_start_decompress(). We can't use "new" here
// because we are inside the setjmp() block and an error
// in the jpeg input stream would cause a memory leak.
JSAMPARRAY rows = (info->mem->alloc_sarray)
((j_common_ptr)info, JPOOL_IMAGE,
info->output_width * info->output_components, 1);
(void) jpeg_start_decompress(info);
while (info->output_scanline < info->output_height) {
int y = int(info->output_scanline) - clip.y();
if (y >= clip.height())
break; // We've read the entire clip region, so abort.
(void) jpeg_read_scanlines(info, rows, 1);
if (y < 0)
continue; // Haven't reached the starting line yet.
if (info->output_components == 3) {
// Expand 24->32 bpp.
uchar *in = rows[0] + clip.x() * 3;
QRgb *out = (QRgb*)outImage->scanLine(y);
for (int i = 0; i < clip.width(); ++i) {
*out++ = qRgb(in[0], in[1], in[2]);
in += 3;
}
} else if (info->out_color_space == JCS_CMYK) {
// Convert CMYK->RGB.
uchar *in = rows[0] + clip.x() * 4;
QRgb *out = (QRgb*)outImage->scanLine(y);
for (int i = 0; i < clip.width(); ++i) {
int k = in[3];
*out++ = qRgb(k * in[0] / 255, k * in[1] / 255,
k * in[2] / 255);
in += 4;
}
} else if (info->output_components == 1) {
// Grayscale.
memcpy(outImage->scanLine(y),
rows[0] + clip.x(), clip.width());
}
}
} else {
// Load unclipped grayscale data directly into the QImage.
(void) jpeg_start_decompress(info);
while (info->output_scanline < info->output_height) {
uchar *row = outImage->scanLine(info->output_scanline);
(void) jpeg_read_scanlines(info, &row, 1);
}
}
if (info->output_scanline == info->output_height)
(void) jpeg_finish_decompress(info);
if (info->density_unit == 1) {
outImage->setDotsPerMeterX(int(100. * info->X_density / 2.54));
outImage->setDotsPerMeterY(int(100. * info->Y_density / 2.54));
} else if (info->density_unit == 2) {
outImage->setDotsPerMeterX(int(100. * info->X_density));
outImage->setDotsPerMeterY(int(100. * info->Y_density));
}
if (scaledSize.isValid() && scaledSize != clip.size()) {
*outImage = outImage->scaled(scaledSize, Qt::IgnoreAspectRatio, quality >= HIGH_QUALITY_THRESHOLD ? Qt::SmoothTransformation : Qt::FastTransformation);
}
if (!scaledClipRect.isEmpty())
*outImage = outImage->copy(scaledClipRect);
return !outImage->isNull();
}
else
return false;
}
struct my_jpeg_destination_mgr : public jpeg_destination_mgr {
// Nothing dynamic - cannot rely on destruction over longjump
QIODevice *device;
JOCTET buffer[max_buf];
public:
my_jpeg_destination_mgr(QIODevice *);
};
#if defined(Q_C_CALLBACKS)
extern "C" {
#endif
static void qt_init_destination(j_compress_ptr)
{
}
static boolean qt_empty_output_buffer(j_compress_ptr cinfo)
{
my_jpeg_destination_mgr* dest = (my_jpeg_destination_mgr*)cinfo->dest;
int written = dest->device->write((char*)dest->buffer, max_buf);
if (written == -1)
(*cinfo->err->error_exit)((j_common_ptr)cinfo);
dest->next_output_byte = dest->buffer;
dest->free_in_buffer = max_buf;
#if defined(Q_OS_UNIXWARE)
return B_TRUE;
#else
return true;
#endif
}
static void qt_term_destination(j_compress_ptr cinfo)
{
my_jpeg_destination_mgr* dest = (my_jpeg_destination_mgr*)cinfo->dest;
qint64 n = max_buf - dest->free_in_buffer;
qint64 written = dest->device->write((char*)dest->buffer, n);
if (written == -1)
(*cinfo->err->error_exit)((j_common_ptr)cinfo);
}
#if defined(Q_C_CALLBACKS)
}
#endif
inline my_jpeg_destination_mgr::my_jpeg_destination_mgr(QIODevice *device)
{
jpeg_destination_mgr::init_destination = qt_init_destination;
jpeg_destination_mgr::empty_output_buffer = qt_empty_output_buffer;
jpeg_destination_mgr::term_destination = qt_term_destination;
this->device = device;
next_output_byte = buffer;
free_in_buffer = max_buf;
}
static bool can_write_format(QImage::Format fmt)
{
switch (fmt) {
case QImage::Format_Mono:
case QImage::Format_MonoLSB:
case QImage::Format_Indexed8:
case QImage::Format_RGB888:
case QImage::Format_RGB32:
case QImage::Format_ARGB32:
case QImage::Format_ARGB32_Premultiplied:
return true;
break;
default:
break;
}
return false;
}
static bool write_jpeg_image(const QImage &sourceImage, QIODevice *device, int sourceQuality)
{
bool success = false;
const QImage image = can_write_format(sourceImage.format()) ?
sourceImage : sourceImage.convertToFormat(QImage::Format_RGB888);
const QVector<QRgb> cmap = image.colorTable();
struct jpeg_compress_struct cinfo;
JSAMPROW row_pointer[1];
row_pointer[0] = 0;
struct my_jpeg_destination_mgr *iod_dest = new my_jpeg_destination_mgr(device);
struct my_error_mgr jerr;
cinfo.err = jpeg_std_error(&jerr);
jerr.error_exit = my_error_exit;
if (!setjmp(jerr.setjmp_buffer)) {
// WARNING:
// this if loop is inside a setjmp/longjmp branch
// do not create C++ temporaries here because the destructor may never be called
// if you allocate memory, make sure that you can free it (row_pointer[0])
jpeg_create_compress(&cinfo);
cinfo.dest = iod_dest;
cinfo.image_width = image.width();
cinfo.image_height = image.height();
bool gray=false;
switch (image.format()) {
case QImage::Format_Mono:
case QImage::Format_MonoLSB:
case QImage::Format_Indexed8:
gray = true;
for (int i = image.colorCount(); gray && i--;) {
gray = gray & (qRed(cmap[i]) == qGreen(cmap[i]) &&
qRed(cmap[i]) == qBlue(cmap[i]));
}
cinfo.input_components = gray ? 1 : 3;
cinfo.in_color_space = gray ? JCS_GRAYSCALE : JCS_RGB;
break;
default:
cinfo.input_components = 3;
cinfo.in_color_space = JCS_RGB;
}
jpeg_set_defaults(&cinfo);
qreal diffInch = qAbs(image.dotsPerMeterX()*2.54/100. - qRound(image.dotsPerMeterX()*2.54/100.))
+ qAbs(image.dotsPerMeterY()*2.54/100. - qRound(image.dotsPerMeterY()*2.54/100.));
qreal diffCm = (qAbs(image.dotsPerMeterX()/100. - qRound(image.dotsPerMeterX()/100.))
+ qAbs(image.dotsPerMeterY()/100. - qRound(image.dotsPerMeterY()/100.)))*2.54;
if (diffInch < diffCm) {
cinfo.density_unit = 1; // dots/inch
cinfo.X_density = qRound(image.dotsPerMeterX()*2.54/100.);
cinfo.Y_density = qRound(image.dotsPerMeterY()*2.54/100.);
} else {
cinfo.density_unit = 2; // dots/cm
cinfo.X_density = (image.dotsPerMeterX()+50) / 100;
cinfo.Y_density = (image.dotsPerMeterY()+50) / 100;
}
int quality = sourceQuality >= 0 ? qMin(sourceQuality,100) : 75;
#if defined(Q_OS_UNIXWARE)
jpeg_set_quality(&cinfo, quality, B_TRUE /* limit to baseline-JPEG values */);
jpeg_start_compress(&cinfo, B_TRUE);
#else
jpeg_set_quality(&cinfo, quality, true /* limit to baseline-JPEG values */);
jpeg_start_compress(&cinfo, true);
#endif
row_pointer[0] = new uchar[cinfo.image_width*cinfo.input_components];
int w = cinfo.image_width;
while (cinfo.next_scanline < cinfo.image_height) {
uchar *row = row_pointer[0];
switch (image.format()) {
case QImage::Format_Mono:
case QImage::Format_MonoLSB:
if (gray) {
const uchar* data = image.scanLine(cinfo.next_scanline);
if (image.format() == QImage::Format_MonoLSB) {
for (int i=0; i<w; i++) {
bool bit = !!(*(data + (i >> 3)) & (1 << (i & 7)));
row[i] = qRed(cmap[bit]);
}
} else {
for (int i=0; i<w; i++) {
bool bit = !!(*(data + (i >> 3)) & (1 << (7 -(i & 7))));
row[i] = qRed(cmap[bit]);
}
}
} else {
const uchar* data = image.scanLine(cinfo.next_scanline);
if (image.format() == QImage::Format_MonoLSB) {
for (int i=0; i<w; i++) {
bool bit = !!(*(data + (i >> 3)) & (1 << (i & 7)));
*row++ = qRed(cmap[bit]);
*row++ = qGreen(cmap[bit]);
*row++ = qBlue(cmap[bit]);
}
} else {
for (int i=0; i<w; i++) {
bool bit = !!(*(data + (i >> 3)) & (1 << (7 -(i & 7))));
*row++ = qRed(cmap[bit]);
*row++ = qGreen(cmap[bit]);
*row++ = qBlue(cmap[bit]);
}
}
}
break;
case QImage::Format_Indexed8:
if (gray) {
const uchar* pix = image.scanLine(cinfo.next_scanline);
for (int i=0; i<w; i++) {
*row = qRed(cmap[*pix]);
++row; ++pix;
}
} else {
const uchar* pix = image.scanLine(cinfo.next_scanline);
for (int i=0; i<w; i++) {
*row++ = qRed(cmap[*pix]);
*row++ = qGreen(cmap[*pix]);
*row++ = qBlue(cmap[*pix]);
++pix;
}
}
break;
case QImage::Format_RGB888:
memcpy(row, image.scanLine(cinfo.next_scanline), w * 3);
break;
case QImage::Format_RGB32:
case QImage::Format_ARGB32:
case QImage::Format_ARGB32_Premultiplied: {
QRgb* rgb = (QRgb*)image.scanLine(cinfo.next_scanline);
for (int i=0; i<w; i++) {
*row++ = qRed(*rgb);
*row++ = qGreen(*rgb);
*row++ = qBlue(*rgb);
++rgb;
}
break;
}
default:
qWarning("QJpegHandler: unable to write image of format %i",
image.format());
break;
}
jpeg_write_scanlines(&cinfo, row_pointer, 1);
}
jpeg_finish_compress(&cinfo);
jpeg_destroy_compress(&cinfo);
success = true;
} else {
jpeg_destroy_compress(&cinfo);
success = false;
}
delete iod_dest;
delete [] row_pointer[0];
return success;
}
class QJpegHandlerPrivate
{
public:
enum State {
Ready,
ReadHeader,
Error
};
QJpegHandlerPrivate(QJpegHandler *qq)
: quality(75), iod_src(0), state(Ready), q(qq)
{}
~QJpegHandlerPrivate()
{
if(iod_src)
{
jpeg_destroy_decompress(&info);
delete iod_src;
iod_src = 0;
}
}
bool readJpegHeader(QIODevice*);
bool read(QImage *image);
int quality;
QVariant size;
QImage::Format format;
QSize scaledSize;
QRect scaledClipRect;
QRect clipRect;
struct jpeg_decompress_struct info;
struct my_jpeg_source_mgr * iod_src;
struct my_error_mgr err;
State state;
QJpegHandler *q;
};
/*!
\internal
*/
bool QJpegHandlerPrivate::readJpegHeader(QIODevice *device)
{
if(state == Ready)
{
state = Error;
iod_src = new my_jpeg_source_mgr(device);
jpeg_create_decompress(&info);
info.src = iod_src;
info.err = jpeg_std_error(&err);
err.error_exit = my_error_exit;
if (!setjmp(err.setjmp_buffer)) {
#if defined(Q_OS_UNIXWARE)
(void) jpeg_read_header(&info, B_TRUE);
#else
(void) jpeg_read_header(&info, true);
#endif
int width = 0;
int height = 0;
read_jpeg_size(width, height, &info);
size = QSize(width, height);
format = QImage::Format_Invalid;
read_jpeg_format(format, &info);
state = ReadHeader;
return true;
}
else
{
return false;
}
}
else if(state == Error)
return false;
return true;
}
bool QJpegHandlerPrivate::read(QImage *image)
{
if(state == Ready)
readJpegHeader(q->device());
if(state == ReadHeader)
{
bool success = read_jpeg_image(image, scaledSize, scaledClipRect, clipRect, quality, &info, &err);
state = success ? Ready : Error;
return success;
}
return false;
}
QJpegHandler::QJpegHandler()
: d(new QJpegHandlerPrivate(this))
{
}
QJpegHandler::~QJpegHandler()
{
delete d;
}
bool QJpegHandler::canRead() const
{
if(d->state == QJpegHandlerPrivate::Ready && !canRead(device()))
return false;
if (d->state != QJpegHandlerPrivate::Error) {
setFormat("jpeg");
return true;
}
return false;
}
bool QJpegHandler::canRead(QIODevice *device)
{
if (!device) {
qWarning("QJpegHandler::canRead() called with no device");
return false;
}
char buffer[2];
if (device->peek(buffer, 2) != 2)
return false;
return uchar(buffer[0]) == 0xff && uchar(buffer[1]) == 0xd8;
}
bool QJpegHandler::read(QImage *image)
{
if (!canRead())
return false;
return d->read(image);
}
bool QJpegHandler::write(const QImage &image)
{
return write_jpeg_image(image, device(), d->quality);
}
bool QJpegHandler::supportsOption(ImageOption option) const
{
return option == Quality
|| option == ScaledSize
|| option == ScaledClipRect
|| option == ClipRect
|| option == Size
|| option == ImageFormat;
}
QVariant QJpegHandler::option(ImageOption option) const
{
switch(option) {
case Quality:
return d->quality;
case ScaledSize:
return d->scaledSize;
case ScaledClipRect:
return d->scaledClipRect;
case ClipRect:
return d->clipRect;
case Size:
d->readJpegHeader(device());
return d->size;
case ImageFormat:
d->readJpegHeader(device());
return d->format;
default:
return QVariant();
}
}
void QJpegHandler::setOption(ImageOption option, const QVariant &value)
{
switch(option) {
case Quality:
d->quality = value.toInt();
break;
case ScaledSize:
d->scaledSize = value.toSize();
break;
case ScaledClipRect:
d->scaledClipRect = value.toRect();
break;
case ClipRect:
d->clipRect = value.toRect();
break;
default:
break;
}
}
QByteArray QJpegHandler::name() const
{
return "jpeg";
}
QT_END_NAMESPACE