[vlc-devel] [PATCH 02/33] qt: add ImageLuminanceExtractor util class
Prince Gupta
guptaprince8832 at gmail.com
Wed Feb 3 10:56:18 UTC 2021
---
modules/gui/qt/Makefile.am | 2 +
modules/gui/qt/maininterface/mainui.cpp | 2 +
.../gui/qt/util/imageluminanceextractor.cpp | 123 ++++++++++++++++++
.../gui/qt/util/imageluminanceextractor.hpp | 76 +++++++++++
4 files changed, 203 insertions(+)
create mode 100644 modules/gui/qt/util/imageluminanceextractor.cpp
create mode 100644 modules/gui/qt/util/imageluminanceextractor.hpp
diff --git a/modules/gui/qt/Makefile.am b/modules/gui/qt/Makefile.am
index ca4fc8756d..7a2665d0a1 100644
--- a/modules/gui/qt/Makefile.am
+++ b/modules/gui/qt/Makefile.am
@@ -201,6 +201,7 @@ libqt_plugin_la_SOURCES = \
gui/qt/util/audio_device_model.cpp \
gui/qt/util/audio_device_model.hpp \
gui/qt/util/color_scheme_model.cpp gui/qt/util/color_scheme_model.hpp \
+ gui/qt/util/imageluminanceextractor.cpp gui/qt/util/imageluminanceextractor.hpp \
gui/qt/util/imagehelper.cpp gui/qt/util/imagehelper.hpp \
gui/qt/util/i18n.cpp gui/qt/util/i18n.hpp \
gui/qt/util/listcache.hpp \
@@ -345,6 +346,7 @@ nodist_libqt_plugin_la_SOURCES = \
gui/qt/util/asynctask.moc.cpp \
gui/qt/util/audio_device_model.moc.cpp \
gui/qt/util/color_scheme_model.moc.cpp \
+ gui/qt/util/imageluminanceextractor.moc.cpp \
gui/qt/util/i18n.moc.cpp \
gui/qt/util/listcache.moc.cpp \
gui/qt/util/navigation_history.moc.cpp \
diff --git a/modules/gui/qt/maininterface/mainui.cpp b/modules/gui/qt/maininterface/mainui.cpp
index a91dcd6c8a..02d9cab54b 100644
--- a/modules/gui/qt/maininterface/mainui.cpp
+++ b/modules/gui/qt/maininterface/mainui.cpp
@@ -22,6 +22,7 @@
#include "util/qml_main_context.hpp"
#include "util/qmleventfilter.hpp"
+#include "util/imageluminanceextractor.hpp"
#include "util/i18n.hpp"
#include "util/systempalette.hpp"
#include "util/sortfilterproxymodel.hpp"
@@ -197,6 +198,7 @@ void MainUI::registerQMLTypes()
qmlRegisterType<NetworkSourcesModel>( "org.videolan.vlc", 0, 1, "NetworkSourcesModel");
qmlRegisterType<ServicesDiscoveryModel>( "org.videolan.vlc", 0, 1, "ServicesDiscoveryModel");
qmlRegisterType<MlFoldersModel>( "org.videolan.vlc", 0, 1, "MLFolderModel");
+ qmlRegisterType<ImageLuminanceExtractor>( "org.videolan.vlc", 0, 1, "ImageLuminanceExtractor");
qmlRegisterUncreatableType<NavigationHistory>("org.videolan.vlc", 0, 1, "History", "Type of global variable history" );
diff --git a/modules/gui/qt/util/imageluminanceextractor.cpp b/modules/gui/qt/util/imageluminanceextractor.cpp
new file mode 100644
index 0000000000..816819245a
--- /dev/null
+++ b/modules/gui/qt/util/imageluminanceextractor.cpp
@@ -0,0 +1,123 @@
+/*****************************************************************************
+ * Copyright (C) 2021 the VideoLAN team
+ *
+ * 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.
+ *****************************************************************************/
+
+#include <QImage>
+#include <QColor>
+
+#include "imageluminanceextractor.hpp"
+
+ImageLuminanceExtractor::ImageLuminanceExtractor(QObject *parent) : QObject(parent) {}
+
+QUrl ImageLuminanceExtractor::source() const
+{
+ return m_source;
+}
+
+int ImageLuminanceExtractor::luminance() const
+{
+ return m_luminance;
+}
+
+bool ImageLuminanceExtractor::isEnabled() const
+{
+ return m_enabled;
+}
+
+void ImageLuminanceExtractor::setLuminance(const int luminance)
+{
+ m_luminance = luminance;
+ emit luminanceChanged(m_luminance);
+}
+
+void ImageLuminanceExtractor::setSource(const QUrl &source)
+{
+ if (m_source == source)
+ return;
+
+ m_source = source;
+ if (m_enabled)
+ startTask();
+ else
+ m_pendingUpdate = true;
+ emit sourceChanged(m_source);
+}
+
+void ImageLuminanceExtractor::setIsEnabled(const bool enabled)
+{
+ if (m_enabled == enabled)
+ return;
+
+ m_enabled = enabled;
+ if (m_enabled && m_pendingUpdate)
+ startTask();
+ emit enabledChanged(m_enabled);
+}
+
+void ImageLuminanceExtractor::startTask()
+{
+ m_pendingUpdate = false;
+ m_task.reset(new LuminanceCalculator(m_source));
+ connect(m_task.get(), &LuminanceCalculator::result, this, [this]()
+ {
+ LuminanceCalculator *task = static_cast<LuminanceCalculator *>(sender());
+ assert(task == m_task.get());
+
+ int result = task->takeResult();
+ if (result != Status::FAILED)
+ setLuminance(result);
+ else
+ qWarning("luminance extraction failed");
+
+ m_task.reset();
+ });
+
+ m_task->start(*QThreadPool::globalInstance());
+}
+
+ImageLuminanceExtractor::LuminanceCalculator::LuminanceCalculator(const QUrl &source) : m_source {source} {}
+
+int ImageLuminanceExtractor::LuminanceCalculator::execute()
+{
+ QString path = m_source.isLocalFile() ? m_source.toLocalFile() : m_source.toString();
+ if (path.startsWith("qrc:///"))
+ path.replace(0, strlen("qrc:///"), ":/");
+ else if (!m_source.isLocalFile())
+ return Status::FAILED;
+
+ const QImage image = QImage(path).scaled(128, 128, Qt::KeepAspectRatio);
+ if (image.isNull())
+ return Status::FAILED;
+
+ int lumimance = 0;
+ size_t count = 0;
+ for (int i = 0; i < image.width(); i++)
+ {
+ for (int j = 0; j < image.height(); j++)
+ {
+ const QColor pixelColor = image.pixelColor(i, j);
+ if (!pixelColor.isValid())
+ continue;
+
+ lumimance += 0.299*pixelColor.red() + 0.587*pixelColor.green() + 0.144*pixelColor.blue();
+ count++;
+ }
+ }
+
+ lumimance = (lumimance / count);
+ return lumimance;
+}
diff --git a/modules/gui/qt/util/imageluminanceextractor.hpp b/modules/gui/qt/util/imageluminanceextractor.hpp
new file mode 100644
index 0000000000..5e553c5028
--- /dev/null
+++ b/modules/gui/qt/util/imageluminanceextractor.hpp
@@ -0,0 +1,76 @@
+/*****************************************************************************
+ * Copyright (C) 2021 the VideoLAN team
+ *
+ * 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 IMAGELUMINANCEXTRACTOR_HPP
+#define IMAGELUMINANCEXTRACTOR_HPP
+
+#include <QUrl>
+
+#include "util/asynctask.hpp"
+
+class ImageLuminanceExtractor : public QObject
+{
+ Q_OBJECT
+ Q_PROPERTY(QUrl source READ source WRITE setSource NOTIFY sourceChanged)
+ Q_PROPERTY(int luminance READ luminance NOTIFY luminanceChanged)
+ Q_PROPERTY(bool enabled READ isEnabled WRITE setIsEnabled NOTIFY enabledChanged)
+
+public:
+ enum Status
+ {
+ FAILED = -1
+ };
+
+ ImageLuminanceExtractor(QObject *parent = nullptr);
+
+ QUrl source() const;
+ int luminance() const;
+ bool isEnabled() const;
+
+public slots:
+ void setSource(const QUrl &source);
+ void setIsEnabled(bool enabled);
+
+signals:
+ void sourceChanged(QUrl source);
+ void luminanceChanged(int luminance);
+ void enabledChanged(bool enabled);
+
+private:
+ class LuminanceCalculator : public AsyncTask<int>
+ {
+ public:
+ LuminanceCalculator(const QUrl &source);
+
+ int execute() override;
+
+ private:
+ QUrl m_source;
+ };
+
+ void startTask();
+ void setLuminance(int luminance);
+
+ QUrl m_source;
+ TaskHandle<LuminanceCalculator> m_task;
+ int m_luminance = 0;
+ bool m_enabled = false;
+ bool m_pendingUpdate = false;
+};
+
+#endif // IMAGELUMINANCEXTRACTOR_HPP
--
2.25.1
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