C++/Qt/QImage

Материал из C\C++ эксперт
Версия от 10:25, 25 мая 2010; Admin (обсуждение | вклад) (1 версия: Импорт контента...)
(разн.) ← Предыдущая | Текущая версия (разн.) | Следующая → (разн.)
Перейти к: навигация, поиск

Check image format and scan line

  
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** 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.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/
#include <QtGui>
int main()
{
    int x, y;
    {
        QImage image;
        if (image.format() == QImage::Format_MonoLSB)
            image.scanLine(y)[x >> 3] |= 1 << (x & 7);
        else
            image.scanLine(y)[x >> 3] |= 1 << (7 - (x & 7));
    }

}


Image composer

  
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** 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.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/
#ifndef IMAGECOMPOSER_H
#define IMAGECOMPOSER_H
#include <QPainter>
#include <QWidget>
QT_BEGIN_NAMESPACE
class QComboBox;
class QLabel;
class QToolButton;
QT_END_NAMESPACE

class ImageComposer : public QWidget
{
    Q_OBJECT
public:
    ImageComposer();
private slots:
    void chooseSource();
    void chooseDestination();
    void recalculateResult();

private:
    void addOp(QPainter::CompositionMode mode, const QString &name);
    void chooseImage(const QString &title, QImage *image, QToolButton *button);
    void loadImage(const QString &fileName, QImage *image, QToolButton *button);
    QPainter::CompositionMode currentMode() const;
    QPoint imagePos(const QImage &image) const;
    QToolButton *sourceButton;
    QToolButton *destinationButton;
    QComboBox *operatorComboBox;
    QLabel *equalLabel;
    QLabel *resultLabel;
    QImage sourceImage;
    QImage destinationImage;
    QImage resultImage;
};

#endif



#include <QtGui>
#include "imagecomposer.h"

static const QSize resultSize(200, 200);

ImageComposer::ImageComposer()
{
    sourceButton = new QToolButton;
    sourceButton->setIconSize(resultSize);
    operatorComboBox = new QComboBox;
    addOp(QPainter::CompositionMode_SourceOver, tr("SourceOver"));
    addOp(QPainter::CompositionMode_DestinationOver, tr("DestinationOver"));
    addOp(QPainter::CompositionMode_Clear, tr("Clear"));
    addOp(QPainter::CompositionMode_Source, tr("Source"));
    addOp(QPainter::CompositionMode_Destination, tr("Destination"));
    addOp(QPainter::CompositionMode_SourceIn, tr("SourceIn"));
    addOp(QPainter::CompositionMode_DestinationIn, tr("DestinationIn"));
    addOp(QPainter::CompositionMode_SourceOut, tr("SourceOut"));
    addOp(QPainter::CompositionMode_DestinationOut, tr("DestinationOut"));
    addOp(QPainter::CompositionMode_SourceAtop, tr("SourceAtop"));
    addOp(QPainter::CompositionMode_DestinationAtop, tr("DestinationAtop"));
    addOp(QPainter::CompositionMode_Xor, tr("Xor"));
    addOp(QPainter::CompositionMode_Plus, tr("Plus"));
    addOp(QPainter::CompositionMode_Multiply, tr("Multiply"));
    addOp(QPainter::CompositionMode_Screen, tr("Screen"));
    addOp(QPainter::CompositionMode_Overlay, tr("Overlay"));
    addOp(QPainter::CompositionMode_Darken, tr("Darken"));
    addOp(QPainter::CompositionMode_Lighten, tr("Lighten"));
    addOp(QPainter::CompositionMode_ColorDodge, tr("ColorDodge"));
    addOp(QPainter::CompositionMode_ColorBurn, tr("ColorBurn"));
    addOp(QPainter::CompositionMode_HardLight, tr("HardLight"));
    addOp(QPainter::CompositionMode_SoftLight, tr("SoftLight"));
    addOp(QPainter::CompositionMode_Difference, tr("Difference"));
    addOp(QPainter::CompositionMode_Exclusion, tr("Exclusion"));

    destinationButton = new QToolButton;
    destinationButton->setIconSize(resultSize);
    equalLabel = new QLabel(tr("="));
    resultLabel = new QLabel;
    resultLabel->setMinimumWidth(resultSize.width());

    connect(sourceButton, SIGNAL(clicked()), this, SLOT(chooseSource()));
    connect(operatorComboBox, SIGNAL(activated(int)),
            this, SLOT(recalculateResult()));
    connect(destinationButton, SIGNAL(clicked()),
            this, SLOT(chooseDestination()));

    QGridLayout *mainLayout = new QGridLayout;
    mainLayout->addWidget(sourceButton, 0, 0, 3, 1);
    mainLayout->addWidget(operatorComboBox, 1, 1);
    mainLayout->addWidget(destinationButton, 0, 2, 3, 1);
    mainLayout->addWidget(equalLabel, 1, 3);
    mainLayout->addWidget(resultLabel, 0, 4, 3, 1);
    mainLayout->setSizeConstraint(QLayout::SetFixedSize);
    setLayout(mainLayout);

    resultImage = QImage(resultSize, QImage::Format_ARGB32_Premultiplied);
    loadImage(":/images/butterfly.png", &sourceImage, sourceButton);
    loadImage(":/images/checker.png", &destinationImage, destinationButton);
    setWindowTitle(tr("Image Composition"));
}

void ImageComposer::chooseSource()
{
    chooseImage(tr("Choose Source Image"), &sourceImage, sourceButton);
}

void ImageComposer::chooseDestination()
{
    chooseImage(tr("Choose Destination Image"), &destinationImage,
                destinationButton);
}

void ImageComposer::recalculateResult()
{
    QPainter::CompositionMode mode = currentMode();
    QPainter painter(&resultImage);
    painter.setCompositionMode(QPainter::CompositionMode_Source);
    painter.fillRect(resultImage.rect(), Qt::transparent);
    painter.setCompositionMode(QPainter::CompositionMode_SourceOver);
    painter.drawImage(0, 0, destinationImage);
    painter.setCompositionMode(mode);
    painter.drawImage(0, 0, sourceImage);
    painter.setCompositionMode(QPainter::CompositionMode_DestinationOver);
    painter.fillRect(resultImage.rect(), Qt::white);
    painter.end();
    resultLabel->setPixmap(QPixmap::fromImage(resultImage));
}

void ImageComposer::addOp(QPainter::CompositionMode mode, const QString &name)
{
    operatorComboBox->addItem(name, mode);
}

void ImageComposer::chooseImage(const QString &title, QImage *image,
                                QToolButton *button)
{
    QString fileName = QFileDialog::getOpenFileName(this, title);
    if (!fileName.isEmpty())
        loadImage(fileName, image, button);
}

void ImageComposer::loadImage(const QString &fileName, QImage *image,
                              QToolButton *button)
{
    image->load(fileName);
    QImage fixedImage(resultSize, QImage::Format_ARGB32_Premultiplied);
    QPainter painter(&fixedImage);
    painter.setCompositionMode(QPainter::CompositionMode_Source);
    painter.fillRect(fixedImage.rect(), Qt::transparent);
    painter.setCompositionMode(QPainter::CompositionMode_SourceOver);
    painter.drawImage(imagePos(*image), *image);
    painter.end();
    button->setIcon(QPixmap::fromImage(fixedImage));
    *image = fixedImage;
    recalculateResult();
}

QPainter::CompositionMode ImageComposer::currentMode() const
{
    return (QPainter::CompositionMode)
           operatorComboBox->itemData(operatorComboBox->currentIndex()).toInt();
}

QPoint ImageComposer::imagePos(const QImage &image) const
{
    return QPoint((resultSize.width() - image.width()) / 2,
                  (resultSize.height() - image.height()) / 2);
}



#include <QApplication>
#include "imagecomposer.h"

int main(int argc, char *argv[])
{
    Q_INIT_RESOURCE(imagecomposition);
    QApplication app(argc, argv);
    ImageComposer composer;
    composer.show();
    return app.exec();
}


Set entry 19 in the color table to yellow

  
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** 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.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/
#include <QtGui>
int main()
{
    int x, y;
    {
        // 8-BIT ACCESS
        QImage image;
        // set entry 19 in the color table to yellow
        image.setColor(19, qRgb(255, 255, 0));
        // set 8 bit pixel at (x,y) to value yellow (in color table)
        image.scanLine(y)[x] = 19;
    }

}


Sets 32 bit pixel at (x,y) to yellow

  
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** 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.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/
#include <QtGui>
int main()
{
    int x, y;
    {
        // 32-BIT
        QImage image;
        // sets 32 bit pixel at (x,y) to yellow.
        uint *ptr = reinterpret_cast<uint *>(image.scanLine(y)) + x;
        *ptr = qRgb(255, 255, 0);
    }

}


svg text object

  
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** 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.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/
#ifndef SVGTEXTOBJECT_H
#define SVGTEXTOBJECT_H
#include <QTextObjectInterface>
QT_BEGIN_NAMESPACE
class QTextDocument;
class QTextFormat;
class QPainter;
class QRectF;
class QSizeF;
QT_END_NAMESPACE
 
class SvgTextObject : public QObject, public QTextObjectInterface
{
    Q_OBJECT
    Q_INTERFACES(QTextObjectInterface)

public:        
    QSizeF intrinsicSize(QTextDocument *doc, int posInDocument,
                         const QTextFormat &format);
    void drawObject(QPainter *painter, const QRectF &rect, QTextDocument *doc,
                    int posInDocument, const QTextFormat &format);
};

#endif






#include <QtGui>
#include <QtSvg>
#include "svgtextobject.h"
#include "window.h"

QSizeF SvgTextObject::intrinsicSize(QTextDocument *doc, int posInDocument,
                                    const QTextFormat &format)
{
    QImage bufferedImage = qVariantValue<QImage>(format.property(Window::SvgData));
    QSize size = bufferedImage.size();
    
    if (size.height() > 25)
        size *= 25.0 / (double) size.height();
    return QSizeF(size);
}

void SvgTextObject::drawObject(QPainter *painter, const QRectF &rect,
                               QTextDocument *doc, int posInDocument,
                               const QTextFormat &format)
{
    QImage bufferedImage = qVariantValue<QImage>(format.property(Window::SvgData));
    painter->drawImage(rect, bufferedImage);
}




#ifndef WINDOW_H
#define WINDOW_H
#include <QWidget>
#include <QTextFormat>
QT_BEGIN_NAMESPACE
class QTextEdit;
class QLineEdit;
class QPushButton;
class QLabel;
QT_END_NAMESPACE

class Window : public QWidget
{
    Q_OBJECT
public:
    enum { SvgTextFormat = QTextFormat::UserObject + 1 };
    enum SvgProperties { SvgData = 1 };
    Window();
private slots:
    void insertTextObject();
private:
    void setupTextObject();
    void setupGui();
private:
    QTextEdit *textEdit;
    QLabel *fileNameLabel;
    QLineEdit *fileNameLineEdit;
    QPushButton *insertTextObjectButton;
};

#endif



#include <QtGui>
#include <QtSvg>
#include "window.h"
#include "svgtextobject.h"
Window::Window()
{
    setupGui();
    setupTextObject();
    setWindowTitle("Text Object Example");
}

void Window::insertTextObject()
{
    QString fileName = fileNameLineEdit->text();
    QFile file(fileName);
    if (!file.open(QIODevice::ReadOnly)) {
        QMessageBox::warning(this, tr("Error Opening File"),
                             tr("Could not open "%1"").arg(fileName));
    }
    QByteArray svgData = file.readAll();

    QTextCharFormat svgCharFormat;
    svgCharFormat.setObjectType(SvgTextFormat);
    QSvgRenderer renderer(svgData);
    QImage svgBufferImage(renderer.defaultSize(), QImage::Format_ARGB32);
    QPainter painter(&svgBufferImage);
    renderer.render(&painter, svgBufferImage.rect());
    svgCharFormat.setProperty(SvgData, svgBufferImage);
    QTextCursor cursor = textEdit->textCursor();
    cursor.insertText(QString(QChar::ObjectReplacementCharacter), svgCharFormat);
    textEdit->setTextCursor(cursor);
}

void Window::setupTextObject()
{
    QObject *svgInterface = new SvgTextObject;
    textEdit->document()->documentLayout()->registerHandler(SvgTextFormat, svgInterface);
}

void Window::setupGui()
{
    fileNameLabel = new QLabel(tr("Svg File Name:"));
    fileNameLineEdit = new QLineEdit;
    insertTextObjectButton = new QPushButton(tr("Insert Image"));
    fileNameLineEdit->setText("./files/heart.svg");
    connect(insertTextObjectButton, SIGNAL(clicked()),
            this, SLOT(insertTextObject()));
    QHBoxLayout *bottomLayout = new QHBoxLayout;
    bottomLayout->addWidget(fileNameLabel);
    bottomLayout->addWidget(fileNameLineEdit);
    bottomLayout->addWidget(insertTextObjectButton);
    textEdit = new QTextEdit;
    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addWidget(textEdit);
    mainLayout->addLayout(bottomLayout);
    setLayout(mainLayout);
}



#include <QtGui>
#include "window.h"
int main(int argv, char **args)
{
    QApplication app(argv, args);
    Window window;
    window.show();
    return app.exec();
}


Writes image into ba in PNG format

  
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** 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.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/
#include <QtGui>
int main()
{
    int x, y;
    {
        QImage image;
        QByteArray ba;
        QBuffer buffer(&ba);
        buffer.open(QIODevice::WriteOnly);
        image.save(&buffer, "PNG"); // writes image into ba in PNG format
    }

}