feat: use libexiv2 to obtain more image metadata

.github/workflows/ubuntu.yml

@@ -10,7 +10,7 @@ jobs:
     steps:
     - uses: actions/checkout@v1
     - name: Get build dept.
-      run: sudo apt install cmake qtbase5-dev libqt5svg5-dev qttools5-dev
+      run: sudo apt install cmake extra-cmake-modules qtbase5-dev libqt5svg5-dev qttools5-dev libexiv2-dev
     - name: Build it
       run: |
         mkdir build

CMakeLists.txt

@@ -9,8 +9,21 @@ set (CMAKE_AUTOMOC ON)
 set (CMAKE_AUTORCC ON)
 set (QT_MINIMUM_VERSION "5.10")
 
+option (EXIV2_METADATA_SUPPORT "Better image metadata support via libexiv2" ON)
+
 find_package(Qt5 ${QT_MINIMUM_VERSION} CONFIG REQUIRED Widgets Svg LinguistTools)
 
+if (EXIV2_METADATA_SUPPORT)
+    find_package(Exiv2)
+    set_package_properties(Exiv2 PROPERTIES
+        URL "https://www.exiv2.org"
+        DESCRIPTION "image metadata support"
+        TYPE OPTIONAL
+        PURPOSE "Bring better image metadata support"
+    )
+endif ()
+
+#LibExiv2_FOUND
 set (PPIC_CPP_FILES
     app/main.cpp
     app/mainwindow.cpp
@@ -25,6 +38,7 @@ set (PPIC_CPP_FILES
     app/aboutdialog.cpp
     app/metadatamodel.cpp
     app/metadatadialog.cpp
+    app/exiv2wrapper.cpp
 )
 
 set (PPIC_HEADER_FILES
@@ -40,6 +54,7 @@ set (PPIC_HEADER_FILES
     app/aboutdialog.h
     app/metadatamodel.h
     app/metadatadialog.h
+    app/exiv2wrapper.h
 )
 
 set (PPIC_QRC_FILES
@@ -72,6 +87,20 @@ add_executable (${EXE_NAME}
 
 target_link_libraries (${EXE_NAME} Qt5::Widgets Qt5::Svg)
 
+if (Exiv2_FOUND)
+    message(INFO ${LibExiv2_INCLUDE_DIRS})
+    target_include_directories(${EXE_NAME}
+    PRIVATE
+        ${LibExiv2_INCLUDE_DIRS}
+    )
+    target_link_libraries (${EXE_NAME}
+        Exiv2
+    )
+    target_compile_definitions(${EXE_NAME} PRIVATE
+        HAVE_EXIV2_VERSION="${LibExiv2_VERSION}"
+    )
+endif ()
+
 # Extra build settings
 if (WIN32)
     set_property (
@@ -194,6 +223,8 @@ install (
     DESTINATION ${QM_FILE_INSTALL_DIR}
 )
 
+feature_summary(WHAT ALL INCLUDE_QUIET_PACKAGES FATAL_ON_MISSING_REQUIRED_PACKAGES)
+
 # CPACK: General Settings
 set (CPACK_GENERATOR "TBZ2")
 set (CPACK_PACKAGE_NAME "pineapple-pictures")
@@ -206,7 +237,7 @@ elseif (APPLE)
     # ...
 elseif (UNIX)
     set (CPACK_SYSTEM_NAME "${CMAKE_SYSTEM_NAME}-${CMAKE_SYSTEM_PROCESSOR}")
-    set (CPACK_DEBIAN_PACKAGE_DEPENDS "libqt5svg5")
+    set (CPACK_DEBIAN_PACKAGE_DEPENDS "libqt5svg5 libexiv2-14")
     set (CPACK_DEBIAN_PACKAGE_RECOMMENDS "kimageformat-plugins")
 endif()
 

app/aboutdialog.cpp

@@ -109,6 +109,9 @@ SOFTWARE.
         QStringLiteral("<h1 align='center'><b>%1</b></h1>").arg(tr("Third-party Libraries used by %1")),
         tr("%1 is built on the following free software libraries:"),
         QStringLiteral("<ul>"),
+#ifdef HAVE_EXIV2_VERSION
+        QStringLiteral("<li><a href='%1'>%2</a>: %3</li>").arg("https://www.exiv2.org/", "Exiv2", "GPLv2"),
+#endif // EXIV2_VERSION
         QStringLiteral("<li><a href='%1'>%2</a>: %3</li>").arg("https://www.qt.io/", "Qt", "GPLv2 + GPLv3 + LGPLv2.1 + LGPLv3"),
         QStringLiteral("</ul>")
     };

app/exiv2wrapper.cpp

@@ -0,0 +1,100 @@
+#include "exiv2wrapper.h"
+
+#ifdef HAVE_EXIV2_VERSION
+#include <exiv2/exiv2.hpp>
+#else // HAVE_EXIV2_VERSION
+namespace Exiv2 {
+class Image {};
+}
+#endif // HAVE_EXIV2_VERSION
+
+#include <sstream>
+
+#include <QFile>
+#include <QDebug>
+
+Exiv2Wrapper::Exiv2Wrapper()
+{
+
+}
+
+Exiv2Wrapper::~Exiv2Wrapper()
+{
+
+}
+
+template<typename Collection, typename Iterator>
+void Exiv2Wrapper::cacheSection(Collection collection)
+{
+    const Collection& exifData = collection;
+    Iterator it = exifData.begin(), end = exifData.end();
+    for (; it != end; ++it) {
+        QString key = QString::fromUtf8(it->key().c_str());
+        QString label = QString::fromLocal8Bit(it->tagLabel().c_str());
+        std::ostringstream stream;
+        stream << *it;
+        QString value = QString::fromLocal8Bit(stream.str().c_str());
+        m_metadataValue.insert(key, value);
+        m_metadataLabel.insert(key, label);
+
+        qDebug() << key << label << value;
+    }
+}
+
+bool Exiv2Wrapper::load(const QString &filePath)
+{
+#ifdef HAVE_EXIV2_VERSION
+    QByteArray filePathByteArray = QFile::encodeName(filePath);
+    try {
+        m_exivImage.reset(Exiv2::ImageFactory::open(filePathByteArray.constData()).release());
+        m_exivImage->readMetadata();
+    } catch (const Exiv2::Error& error) {
+        m_errMsg = QString::fromUtf8(error.what());
+        return false;
+    }
+    return true;
+#else // HAVE_EXIV2_VERSION
+    Q_UNUSED(filePath);
+    return false;
+#endif // HAVE_EXIV2_VERSION
+}
+
+void Exiv2Wrapper::cacheSections()
+{
+#ifdef HAVE_EXIV2_VERSION
+    if (m_exivImage->checkMode(Exiv2::mdExif) & Exiv2::amRead) {
+        cacheSection<Exiv2::ExifData, Exiv2::ExifData::const_iterator>(m_exivImage->exifData());
+    }
+
+    if (m_exivImage->checkMode(Exiv2::mdIptc) & Exiv2::amRead) {
+        cacheSection<Exiv2::IptcData, Exiv2::IptcData::const_iterator>(m_exivImage->iptcData());
+    }
+
+    if (m_exivImage->checkMode(Exiv2::mdXmp) & Exiv2::amRead) {
+        cacheSection<Exiv2::XmpData, Exiv2::XmpData::const_iterator>(m_exivImage->xmpData());
+    }
+
+//    qDebug() << m_metadataValue;
+//    qDebug() << m_metadataLabel;
+#endif // HAVE_EXIV2_VERSION
+}
+
+QString Exiv2Wrapper::comment() const
+{
+#ifdef HAVE_EXIV2_VERSION
+    return m_exivImage->comment().c_str();
+#else // HAVE_EXIV2_VERSION
+    return QString();
+#endif // HAVE_EXIV2_VERSION
+}
+
+QString Exiv2Wrapper::label(const QString &key) const
+{
+    return m_metadataLabel.value(key);
+}
+
+QString Exiv2Wrapper::value(const QString &key) const
+{
+    return m_metadataValue.value(key);
+}
+

app/exiv2wrapper.h

@@ -0,0 +1,36 @@
+#ifndef EXIV2WRAPPER_H
+#define EXIV2WRAPPER_H
+
+#include <memory>
+
+#include <QString>
+#include <QMap>
+
+namespace Exiv2 {
+class Image;
+}
+
+class Exiv2Wrapper
+{
+public:
+    Exiv2Wrapper();
+    ~Exiv2Wrapper();
+
+    bool load(const QString& filePath);
+    void cacheSections();
+
+    QString comment() const;
+    QString label(const QString & key) const;
+    QString value(const QString & key) const;
+
+private:
+    std::unique_ptr<Exiv2::Image> m_exivImage;
+    QMap<QString, QString> m_metadataValue;
+    QMap<QString, QString> m_metadataLabel;
+    QString m_errMsg;
+
+    template<typename Collection, typename Iterator>
+    void cacheSection(Collection collection);
+};
+
+#endif // EXIV2WRAPPER_H

app/metadatamodel.cpp

@@ -1,4 +1,5 @@
 #include "metadatamodel.h"
+#include "exiv2wrapper.h"
 
 #include <QDebug>
 #include <QDateTime>
@@ -31,14 +32,12 @@ void MetadataModel::setFile(const QString &imageFilePath)
     const QString & imageDimensionsString = imageSize(imgReader.size());
     const QString & imageRatioString = imageSizeRatio(imgReader.size());
 
-#if 0
     appendSection(QStringLiteral("Description"), tr("Description", "Section name."));
     appendSection(QStringLiteral("Origin"), tr("Origin", "Section name."));
-#endif // 0
     appendSection(QStringLiteral("Image"), tr("Image", "Section name."));
-#if 0
     appendSection(QStringLiteral("Camera"), tr("Camera", "Section name."));
     appendSection(QStringLiteral("AdvancedPhoto"), tr("Advanced photo", "Section name."));
+#if 0
     appendSection(QStringLiteral("GPS"), tr("GPS", "Section name."));
 #endif // 0
     appendSection(QStringLiteral("File"), tr("File", "Section name."));
@@ -60,6 +59,31 @@ void MetadataModel::setFile(const QString &imageFilePath)
                    tr("Date Created"), birthTimeString);
     appendProperty(QStringLiteral("File"), QStringLiteral("File.LastModified"),
                    tr("Date Modified"), lastModifiedTimeString);
+
+    Exiv2Wrapper wrapper;
+    if (wrapper.load(imageFilePath)) {
+        wrapper.cacheSections();
+
+        appendProperty(QStringLiteral("Description"), QStringLiteral("Description.Comments"),
+                       tr("Comments"), wrapper.comment());
+
+        appendExivPropertyIfExist(wrapper, QStringLiteral("Origin"),
+                                  QStringLiteral("Exif.Image.Software"), tr("Program name"));
+        appendExivPropertyIfExist(wrapper, QStringLiteral("Image"),
+                                  QStringLiteral("Exif.Photo.ColorSpace"), tr("Colour representation"));
+        appendExivPropertyIfExist(wrapper, QStringLiteral("Camera"),
+                                  QStringLiteral("Exif.Image.Make"), tr("Camera maker"));
+        appendExivPropertyIfExist(wrapper, QStringLiteral("Camera"),
+                                  QStringLiteral("Exif.Image.Model"), tr("Camera model"));
+        appendExivPropertyIfExist(wrapper, QStringLiteral("Camera"),
+                                  QStringLiteral("Exif.Photo.ISOSpeedRatings"), tr("ISO speed"));
+        appendExivPropertyIfExist(wrapper, QStringLiteral("Camera"),
+                                  QStringLiteral("Exif.Photo.FocalLength"), tr("Focal length"));
+        appendExivPropertyIfExist(wrapper, QStringLiteral("AdvancedPhoto"),
+                                  QStringLiteral("Exif.Photo.DigitalZoomRatio"), tr("Digital zoom"));
+        appendExivPropertyIfExist(wrapper, QStringLiteral("AdvancedPhoto"),
+                                  QStringLiteral("Exif.Photo.ExifVersion"), tr("EXIF version"));
+    }
 }
 
 QString MetadataModel::imageSize(const QSize &size)
@@ -126,6 +150,18 @@ bool MetadataModel::updateProperty(const QString &propertyKey, const QString &pr
     return false;
 }
 
+bool MetadataModel::appendExivPropertyIfExist(const Exiv2Wrapper &wrapper, const QString &sectionKey, const QString &exiv2propertyKey, const QString &propertyDisplayName)
+{
+    const QString & value = wrapper.value(exiv2propertyKey);
+    if (!value.isEmpty()) {
+        appendProperty(sectionKey, exiv2propertyKey,
+                       propertyDisplayName.isEmpty() ? wrapper.label(exiv2propertyKey) : propertyDisplayName,
+                       value);
+        return true;
+    }
+    return false;
+}
+
 QModelIndex MetadataModel::index(int row, int column, const QModelIndex &parent) const
 {
     if (!hasIndex(row, column, parent)) {

app/metadatamodel.h

@@ -3,6 +3,7 @@
 
 #include <QAbstractItemModel>
 
+class Exiv2Wrapper;
 class MetadataModel : public QAbstractItemModel
 {
     Q_OBJECT
@@ -18,6 +19,8 @@ public:
     bool appendProperty(const QString & sectionKey, const QString & propertyKey,
                         const QString & propertyDisplayName, const QString & propertyValue = QString());
     bool updateProperty(const QString & propertyKey, const QString & propertyValue);
+    bool appendExivPropertyIfExist(const Exiv2Wrapper & wrapper, const QString & sectionKey,
+                                   const QString & exiv2propertyKey, const QString & propertyDisplayName = QString());
 
 private:
     enum RowType : quintptr {

pineapple-pictures.pro

@@ -29,7 +29,8 @@ SOURCES += \
     app/settings.cpp \
     app/settingsdialog.cpp \
     app/metadatamodel.cpp \
-    app/metadatadialog.cpp
+    app/metadatadialog.cpp \
+    app/exiv2wrapper.cpp
 
 HEADERS += \
     app/aboutdialog.h \
@@ -43,7 +44,8 @@ HEADERS += \
     app/settings.h \
     app/settingsdialog.h \
     app/metadatamodel.h \
-    app/metadatadialog.h
+    app/metadatadialog.h \
+    app/exiv2wrapper.h
 
 TRANSLATIONS = \
     translations/PineapplePictures.ts \