Qt 4.6: extrafiltersplugin.cpp Example File (tools/plugandpaintplugins/extrafilters/extrafiltersplugin.cpp)

|  | Home · All Classes · Overviews |

# extrafiltersplugin.cpp Example File
tools/plugandpaintplugins/extrafilters/extrafiltersplugin.cpp

     /****************************************************************************
     **
     ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
     ** Contact: Nokia Corporation (qt-info@nokia.com)
     **
     ** This file is part of the examples 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.
     **
     **
     **
     **
     **
     **
     **
     **
     ** $QT_END_LICENSE$
     **
     ****************************************************************************/

     #include <QtGui>

     #include <math.h>
     #include <stdlib.h>

     #include "extrafiltersplugin.h"

     QStringList ExtraFiltersPlugin::filters() const
     {
         return QStringList() << tr("Flip Horizontally") << tr("Flip Vertically")
                              << tr("Smudge...") << tr("Threshold...");
     }

     QImage ExtraFiltersPlugin::filterImage(const QString &filter,
                                            const QImage &image, QWidget *parent)
     {
         QImage original = image.convertToFormat(QImage::Format_RGB32);
         QImage result = original;

         if (filter == tr("Flip Horizontally")) {
             for (int y = 0; y < original.height(); ++y) {
                 for (int x = 0; x < original.width(); ++x) {
                     int pixel = original.pixel(original.width() - x - 1, y);
                     result.setPixel(x, y, pixel);
                 }
             }
         } else if (filter == tr("Flip Vertically")) {
             for (int y = 0; y < original.height(); ++y) {
                 for (int x = 0; x < original.width(); ++x) {
                     int pixel = original.pixel(x, original.height() - y - 1);
                     result.setPixel(x, y, pixel);
                 }
             }
         } else if (filter == tr("Smudge...")) {
             bool ok;
             int numIters = QInputDialog::getInteger(parent, tr("Smudge Filter"),
                                         tr("Enter number of iterations:"),
                                         5, 1, 20, 1, &ok);
             if (ok) {
                 for (int i = 0; i < numIters; ++i) {
                     for (int y = 1; y < original.height() - 1; ++y) {
                         for (int x = 1; x < original.width() - 1; ++x) {
                             int p1 = original.pixel(x, y);
                             int p2 = original.pixel(x, y + 1);
                             int p3 = original.pixel(x, y - 1);
                             int p4 = original.pixel(x + 1, y);
                             int p5 = original.pixel(x - 1, y);

                             int red = (qRed(p1) + qRed(p2) + qRed(p3) + qRed(p4)
                                        + qRed(p5)) / 5;
                             int green = (qGreen(p1) + qGreen(p2) + qGreen(p3)
                                          + qGreen(p4) + qGreen(p5)) / 5;
                             int blue = (qBlue(p1) + qBlue(p2) + qBlue(p3)
                                         + qBlue(p4) + qBlue(p5)) / 5;
                             int alpha = (qAlpha(p1) + qAlpha(p2) + qAlpha(p3)
                                          + qAlpha(p4) + qAlpha(p5)) / 5;

                             result.setPixel(x, y, qRgba(red, green, blue, alpha));
                         }
                     }
                 }
             }
         } else if (filter == tr("Threshold...")) {
             bool ok;
             int threshold = QInputDialog::getInteger(parent, tr("Threshold Filter"),
                                                      tr("Enter threshold:"),
                                                      10, 1, 256, 1, &ok);
             if (ok) {
                 int factor = 256 / threshold;
                 for (int y = 0; y < original.height(); ++y) {
                     for (int x = 0; x < original.width(); ++x) {
                         int pixel = original.pixel(x, y);
                         result.setPixel(x, y, qRgba(qRed(pixel) / factor * factor,
                                                     qGreen(pixel) / factor * factor,
                                                     qBlue(pixel) / factor * factor,
                                                     qAlpha(pixel)));
                     }
                 }
             }
         }
         return result;
     }

     Q_EXPORT_PLUGIN2(pnp_extrafilters, ExtraFiltersPlugin)