Add possibility to change brightness & contrast & gamma

BUG: 82979

app/gwenviewui.rc

 <?xml version="1.0"?>
 <!DOCTYPE gui SYSTEM "kpartgui.dtd">
-<gui name="gwenview" version="66">
+<gui name="gwenview" version="67">
 
 <MenuBar>
     <Menu name="file" >
@@ -67,6 +67,7 @@
         <Separator/>
         <Action name="resize" />
         <Action name="crop" />
+        <Action name="brightness_contrast_gamma" />
         <Action name="red_eye_reduction" />
         <Action name="annotate" />
     </Menu>

app/imageopscontextmanageritem.cpp

@@ -42,6 +42,7 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 #include <lib/annotate/annotatedialog.h>
 #include <lib/annotate/annotateoperation.h>
 #endif
+#include <lib/bcg/bcgtool.h>
 #include <lib/contextmanager.h>
 #include <lib/crop/croptool.h>
 #include <lib/document/documentfactory.h>
@@ -76,6 +77,7 @@ struct ImageOpsContextManagerItem::Private {
     QAction *mFlipAction = nullptr;
     QAction *mResizeAction = nullptr;
     QAction *mCropAction = nullptr;
+    QAction *mBCGAction = nullptr;
     QAction *mRedEyeReductionAction = nullptr;
 #ifdef KIMAGEANNOTATOR_FOUND
     QAction *mAnnotateAction = nullptr;
@@ -117,6 +119,11 @@ struct ImageOpsContextManagerItem::Private {
         mCropAction->setIcon(QIcon::fromTheme(QStringLiteral("transform-crop-and-resize")));
         actionCollection->setDefaultShortcut(mCropAction, Qt::SHIFT | Qt::Key_C);
 
+        mBCGAction = edit->addAction(QStringLiteral("brightness_contrast_gamma"), q, SLOT(startBCG()));
+        mBCGAction->setText(i18nc("@action:intoolbar", "Adjust Brightness/Contrast/Gamma"));
+        mBCGAction->setIcon(QIcon::fromTheme(QStringLiteral("contrast")));
+        actionCollection->setDefaultShortcut(mBCGAction, Qt::SHIFT | Qt::Key_B);
+
         mRedEyeReductionAction = edit->addAction(QStringLiteral("red_eye_reduction"), q, SLOT(startRedEyeReduction()));
         mRedEyeReductionAction->setText(i18n("Reduce Red Eye"));
         mRedEyeReductionAction->setIcon(QIcon::fromTheme(QStringLiteral("redeyes")));
@@ -138,7 +145,8 @@ struct ImageOpsContextManagerItem::Private {
             }
         });
 #endif
-        mActionList << mRotateLeftAction << mRotateRightAction << mMirrorAction << mFlipAction << mResizeAction << mCropAction << mRedEyeReductionAction;
+        mActionList << mRotateLeftAction << mRotateRightAction << mMirrorAction << mFlipAction << mResizeAction << mCropAction << mBCGAction
+        << mRedEyeReductionAction;
 #ifdef KIMAGEANNOTATOR_FOUND
         mActionList << mAnnotateAction;
 #endif
@@ -214,6 +222,7 @@ void ImageOpsContextManagerItem::updateActions()
     d->mFlipAction->setEnabled(canModify);
     d->mResizeAction->setEnabled(canModify);
     d->mCropAction->setEnabled(canModify && viewMainPageIsVisible);
+    d->mBCGAction->setEnabled(canModify && viewMainPageIsVisible);
     d->mRedEyeReductionAction->setEnabled(canModify && viewMainPageIsVisible);
 #ifdef KIMAGEANNOTATOR_FOUND
     d->mAnnotateAction->setEnabled(canModify);
@@ -346,4 +355,22 @@ void ImageOpsContextManagerItem::restoreDefaultImageViewTool()
     d->mMainWindow->setDistractionFreeMode(false);
 }
 
+void ImageOpsContextManagerItem::startBCG()
+{
+    if (!d->ensureEditable()) {
+        return;
+    }
+    RasterImageView *view = d->mMainWindow->viewMainPage()->imageView();
+    if (!view) {
+        qCCritical(GWENVIEW_APP_LOG) << "No RasterImageView available!";
+        return;
+    }
+    auto tool = new BCGTool(view);
+    connect(tool, &BCGTool::imageOperationRequested, this, &ImageOpsContextManagerItem::applyImageOperation);
+    connect(tool, &BCGTool::done, this, &ImageOpsContextManagerItem::restoreDefaultImageViewTool);
+
+    d->mMainWindow->setDistractionFreeMode(true);
+    view->setCurrentTool(tool);
+}
+
 } // namespace

app/imageopscontextmanageritem.h

@@ -52,6 +52,7 @@ private Q_SLOTS:
     void startRedEyeReduction();
     void applyImageOperation(AbstractImageOperation *);
     void restoreDefaultImageViewTool();
+    void startBCG();
 
 private:
     struct Private;

lib/CMakeLists.txt

@@ -41,6 +41,10 @@ include_directories(
     )
 
 set(gwenviewlib_SRCS
+    bcg/bcgimageoperation.cpp
+    bcg/bcgtool.cpp
+    bcg/bcgwidget.cpp
+    bcg/imageutils.cpp
     cms/iccjpeg.c
     cms/cmsprofile.cpp
     cms/cmsprofile_png.cpp

lib/bcg/bcgimageoperation.cpp

+/*
+Gwenview: an image viewer
+Copyright 2022 Ilya Pominov <ipominov@astralinux.ru>
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+This program 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
+*/
+// Self
+#include "bcgimageoperation.h"
+
+// Qt
+#include <QImage>
+
+// KF
+#include <KLocalizedString>
+
+// Local
+#include "document/abstractdocumenteditor.h"
+#include "document/document.h"
+#include "document/documentjob.h"
+#include "gwenview_lib_debug.h"
+#include "imageutils.h"
+
+namespace Gwenview
+{
+class BCGJob : public ThreadedDocumentJob
+{
+public:
+    BCGJob(const BCGImageOperation::BrightnessContrastGamma &bcg)
+        : mBcg(bcg)
+    {
+    }
+
+    void threadedStart() override
+    {
+        if (!checkDocumentEditor()) {
+            return;
+        }
+        QImage img = document()->image();
+        BCGImageOperation::apply(img, mBcg);
+        document()->editor()->setImage(img);
+        setError(NoError);
+    }
+
+private:
+    BCGImageOperation::BrightnessContrastGamma mBcg;
+};
+
+struct BCGImageOperationPrivate {
+    QImage mOriginalImage;
+    BCGImageOperation::BrightnessContrastGamma mBcg;
+};
+
+BCGImageOperation::BCGImageOperation(const BrightnessContrastGamma &bcg)
+    : d(new BCGImageOperationPrivate)
+{
+    setText(i18n("Adjust Brightness/Contrast/Gamma"));
+
+    d->mBcg = bcg;
+}
+
+BCGImageOperation::~BCGImageOperation()
+{
+    delete d;
+}
+
+void BCGImageOperation::redo()
+{
+    d->mOriginalImage = document()->image();
+    redoAsDocumentJob(new BCGJob(d->mBcg));
+}
+
+void BCGImageOperation::undo()
+{
+    if (!document()->editor()) {
+        qCWarning(GWENVIEW_LIB_LOG) << "!document->editor()";
+        return;
+    }
+    document()->editor()->setImage(d->mOriginalImage);
+    finish(true);
+}
+
+void BCGImageOperation::apply(QImage &img, const BrightnessContrastGamma &bcg)
+{
+    if (bcg.brightness != 0) {
+        img = ImageUtils::changeBrightness(img, bcg.brightness);
+    }
+    if (bcg.contrast != 0) {
+        img = ImageUtils::changeContrast(img, bcg.contrast + 100);
+    }
+    if (bcg.gamma != 0) {
+        img = ImageUtils::changeGamma(img, bcg.gamma + 100);
+    }
+}
+
+} // namespace

lib/bcg/bcgimageoperation.h

+/*
+Gwenview: an image viewer
+Copyright 2022 Ilya Pominov <ipominov@astralinux.ru>
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+This program 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
+*/
+#ifndef BCGIMAGEOPERATION_H
+#define BCGIMAGEOPERATION_H
+
+#include <lib/gwenviewlib_export.h>
+
+// Qt
+
+// KF
+
+// Local
+#include <lib/abstractimageoperation.h>
+
+namespace Gwenview
+{
+struct BCGImageOperationPrivate;
+class GWENVIEWLIB_EXPORT BCGImageOperation : public AbstractImageOperation
+{
+    Q_OBJECT
+public:
+    struct BrightnessContrastGamma {
+        int brightness = 0;
+        int contrast = 0;
+        int gamma = 0;
+    };
+
+    BCGImageOperation(const BrightnessContrastGamma &bcg);
+    ~BCGImageOperation() override;
+
+    void redo() override;
+    void undo() override;
+
+    static void apply(QImage &img, const BrightnessContrastGamma &bcg);
+
+private:
+    BCGImageOperationPrivate *const d;
+};
+
+} // namespace
+
+#endif /*BCGIMAGEOPERATION_H */

lib/bcg/bcgtool.cpp

+/*
+Gwenview: an image viewer
+Copyright 2022 Ilya Pominov <ipominov@astralinux.ru>
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+This program 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
+*/
+// Self
+#include "bcgtool.h"
+
+// Qt
+#include <QAbstractButton>
+#include <QDialogButtonBox>
+#include <QPainter>
+
+// KF
+
+// Local
+#include "bcgimageoperation.h"
+#include "bcgwidget.h"
+#include <lib/documentview/rasterimageview.h>
+
+namespace Gwenview
+{
+struct BCGToolPrivate {
+    BCGImageOperation::BrightnessContrastGamma getBcg() const
+    {
+        BCGImageOperation::BrightnessContrastGamma bcg;
+        bcg.brightness = mBCGWidget->brightness();
+        bcg.contrast = mBCGWidget->contrast();
+        bcg.gamma = mBCGWidget->gamma();
+        return bcg;
+    }
+
+    BCGTool *q = nullptr;
+    BCGWidget *mBCGWidget = nullptr;
+    QImage mImage;
+};
+
+BCGTool::BCGTool(RasterImageView *view)
+    : AbstractRasterImageViewTool(view)
+    , d(new BCGToolPrivate)
+{
+    d->q = this;
+    d->mBCGWidget = new BCGWidget;
+    connect(d->mBCGWidget, &BCGWidget::bcgChanged, this, &BCGTool::slotBCGRequested);
+    connect(d->mBCGWidget, &BCGWidget::done, this, [this](bool accept) {
+        if (accept) {
+            auto op = new BCGImageOperation(d->getBcg());
+            Q_EMIT imageOperationRequested(op);
+        }
+        Q_EMIT done();
+    });
+
+    d->mImage = view->document()->image();
+}
+
+BCGTool::~BCGTool()
+{
+    // mBCGWidget is a child of its container not of us, so it is not deleted automatically
+    delete d->mBCGWidget;
+    delete d;
+}
+
+void BCGTool::paint(QPainter *painter)
+{
+    const QRectF docRect = imageView()->mapToView(QRectF(QPointF(), imageView()->documentSize()));
+    painter->eraseRect(docRect);
+
+    painter->drawImage(docRect, d->mImage);
+}
+
+void BCGTool::keyPressEvent(QKeyEvent *event)
+{
+    auto buttons = d->mBCGWidget->findChild<QDialogButtonBox *>();
+    switch (event->key()) {
+    case Qt::Key_Escape:
+        event->accept();
+        Q_EMIT buttons->rejected();
+        break;
+    case Qt::Key_Return:
+    case Qt::Key_Enter: {
+        event->accept();
+        auto focusButton = static_cast<QAbstractButton *>(buttons->focusWidget());
+        if (focusButton && buttons->buttonRole(focusButton) == QDialogButtonBox::RejectRole) {
+            Q_EMIT buttons->rejected();
+        } else {
+            Q_EMIT buttons->accepted();
+        }
+        break;
+    }
+    default:
+        break;
+    }
+}
+
+QWidget *BCGTool::widget() const
+{
+    return d->mBCGWidget;
+}
+
+void BCGTool::slotBCGRequested()
+{
+    d->mImage = imageView()->document()->image();
+    BCGImageOperation::apply(d->mImage, d->getBcg());
+    imageView()->update();
+}
+
+} // namespace

lib/bcg/bcgtool.h

+/*
+Gwenview: an image viewer
+Copyright 2022 Ilya Pominov <ipominov@astralinux.ru>
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+This program 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
+*/
+#ifndef BCGTOOL_H
+#define BCGTOOL_H
+
+#include <lib/gwenviewlib_export.h>
+
+// Qt
+
+// KF
+
+// Local
+#include <lib/documentview/abstractrasterimageviewtool.h>
+
+namespace Gwenview
+{
+class AbstractImageOperation;
+
+struct BCGToolPrivate;
+class GWENVIEWLIB_EXPORT BCGTool : public AbstractRasterImageViewTool
+{
+    Q_OBJECT
+public:
+    BCGTool(RasterImageView *parent);
+    ~BCGTool() override;
+
+    void paint(QPainter *painter) override;
+    void keyPressEvent(QKeyEvent *event) override;
+    QWidget *widget() const override;
+
+Q_SIGNALS:
+    void done();
+    void imageOperationRequested(AbstractImageOperation *);
+
+private Q_SLOTS:
+    void slotBCGRequested();
+
+private:
+    BCGToolPrivate *const d;
+};
+
+} // namespace
+
+#endif /* BCGTOOL_H */

lib/bcg/bcgwidget.cpp

+/*
+Gwenview: an image viewer
+Copyright 2022 Ilya Pominov <ipominov@astralinux.ru>
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+This program 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
+*/
+// Self
+#include "bcgwidget.h"
+
+// Qt
+#include <QDialogButtonBox>
+#include <QFormLayout>
+#include <QPushButton>
+#include <QSlider>
+#include <QSpinBox>
+#include <QTimer>
+#include <QVBoxLayout>
+
+// KF
+#include <KLocalizedString>
+
+// Local
+#include "gwenview_lib_debug.h"
+
+namespace Gwenview
+{
+struct BCGWidgetPrivate {
+    void setupWidgets()
+    {
+        mCompressor = new QTimer(q);
+        mCompressor->setInterval(10);
+        mCompressor->setSingleShot(true);
+        QObject::connect(mCompressor, &QTimer::timeout, q, [this]() {
+            Q_EMIT q->bcgChanged();
+        });
+
+        auto sliderLayout = new QFormLayout;
+        sliderLayout->addRow(i18n("Brightness:"), createSlider(&mBrightness));
+        sliderLayout->addRow(i18n("Contrast:"), createSlider(&mContrast));
+        sliderLayout->addRow(i18n("Gamma:"), createSlider(&mGamma));
+
+        auto layout = new QVBoxLayout;
+        layout->addLayout(sliderLayout);
+
+        auto btnBox = new QDialogButtonBox(QDialogButtonBox::Ok | QDialogButtonBox::Cancel | QDialogButtonBox::Reset);
+        mOkBtn = btnBox->button(QDialogButtonBox::Ok);
+        mOkBtn->setEnabled(false);
+        mResetBtn = btnBox->button(QDialogButtonBox::Reset);
+        mResetBtn->setEnabled(false);
+        QObject::connect(btnBox, &QDialogButtonBox::rejected, q, [this]() {
+            Q_EMIT q->done(false);
+        });
+        QObject::connect(btnBox, &QDialogButtonBox::accepted, q, [this]() {
+            Q_EMIT q->done(true);
+        });
+        QObject::connect(btnBox->button(QDialogButtonBox::Reset), &QAbstractButton::clicked, q, &BCGWidget::reset);
+        layout->addWidget(btnBox);
+
+        q->setLayout(layout);
+    }
+
+    QLayout *createSlider(int *field)
+    {
+        auto slider = new QSlider(Qt::Horizontal);
+        slider->setMinimum(-100);
+        slider->setMaximum(100);
+        auto spinBox = new QSpinBox;
+        spinBox->setMinimum(-100);
+        spinBox->setMaximum(100);
+
+        QObject::connect(slider, &QSlider::valueChanged, spinBox, &QSpinBox::setValue);
+        QObject::connect(spinBox, qOverload<int>(&QSpinBox::valueChanged), q, [this, slider, field](int value) {
+            slider->blockSignals(true);
+            slider->setValue(value);
+            slider->blockSignals(false);
+            *field = value;
+            bool bcgChanged = mBrightness != 0 || mContrast != 0 || mGamma != 0;
+            mOkBtn->setEnabled(bcgChanged);
+            mResetBtn->setEnabled(bcgChanged);
+            mCompressor->start();
+        });
+        QObject::connect(q, &BCGWidget::reset, q, [slider]() {
+            slider->setValue(0);
+        });
+
+        auto layout = new QHBoxLayout;
+        layout->addWidget(slider);
+        layout->addWidget(spinBox);
+        return layout;
+    }
+
+    BCGWidget *q = nullptr;
+    QTimer *mCompressor = nullptr;
+    QAbstractButton *mOkBtn = nullptr;
+    QAbstractButton *mResetBtn = nullptr;
+    int mBrightness = 0;
+    int mContrast = 0;
+    int mGamma = 0;
+};
+
+BCGWidget::BCGWidget()
+    : QWidget(nullptr)
+    , d(new BCGWidgetPrivate)
+{
+    setWindowFlags(Qt::Tool);
+
+    d->q = this;
+    d->setupWidgets();
+}
+
+BCGWidget::~BCGWidget()
+{
+    delete d;
+}
+
+int BCGWidget::brightness() const
+{
+    return d->mBrightness;
+}
+
+int BCGWidget::contrast() const
+{
+    return d->mContrast;
+}
+
+int BCGWidget::gamma() const
+{
+    return d->mGamma;
+}
+
+} // namespace

lib/bcg/bcgwidget.h

+/*
+Gwenview: an image viewer
+Copyright 2022 Ilya Pominov <ipominov@astralinux.ru>
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+This program 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
+*/
+#ifndef BCGWIDGET_H
+#define BCGWIDGET_H