Rescale images used in Input

app/inpututils.cpp

@@ -38,6 +38,8 @@
 #include "qgsunittypes.h"
 #include "qgsfeatureid.h"
 
+#include "imageutils.h"
+
 #include <Qt>
 #include <QDir>
 #include <QFile>
@@ -46,7 +48,6 @@
 #include <algorithm>
 #include <limits>
 #include <math.h>
-
 #include <iostream>
 
 static const QString DATE_TIME_FORMAT = QStringLiteral( "yyMMdd-hhmmss" );
@@ -1625,3 +1626,10 @@ QString InputUtils::iconFromGeometry( const QgsWkbTypes::GeometryType &geometry
     default: return QString( "qrc:/mIconTableLayer.svg" );
   }
 }
+
+bool InputUtils::rescaleImage( const QString &path, QgsProject *activeProject )
+{
+  qDebug() << "rescaleImage called";
+  int quality = activeProject->readNumEntry( QStringLiteral( "Mergin" ), QStringLiteral( "PhotoQuality" ), 0 );
+  return ImageUtils::rescale( path, quality );
+}

app/inpututils.h

@@ -450,6 +450,11 @@ class InputUtils: public QObject
      */
     Q_INVOKABLE void zoomToProject( QgsProject *qgsProject, QgsQuickMapSettings *mapSettings );
 
+    /**
+     * Rescales image according to the project photo quality setting.
+     */
+    Q_INVOKABLE static bool rescaleImage( const QString &path, QgsProject *activeProject );
+
   signals:
     Q_INVOKABLE void showNotificationRequested( const QString &message );
 

app/qml/ExternalResourceBundle.qml

@@ -97,6 +97,11 @@ Item {
          */
         property var confirmImage: function confirmImage(itemWidget, prefixToRelativePath, value) {
           if (value) {
+            console.log("TRY TO RESCALE" + value)
+            if (!__inputUtils.rescaleImage(value, __activeProject.qgsProject))
+            {
+              console.log("RESCALE FAILED" + value)
+            }
             var newCurrentValue = __inputUtils.getRelativePath(value, prefixToRelativePath)
             itemWidget.editorValueChanged(newCurrentValue, newCurrentValue === "" || newCurrentValue === null)
           }

app/sources.pri

@@ -134,7 +134,8 @@ contains(DEFINES, INPUT_TEST) {
       test/testvariablesmanager.cpp \
       test/testformeditors.cpp \
       test/testmodels.cpp \
-      test/testcoreutils.cpp
+      test/testcoreutils.cpp \
+      test/testimageutils.cpp
 
   HEADERS += \
       test/inputtests.h \
@@ -153,7 +154,8 @@ contains(DEFINES, INPUT_TEST) {
       test/testvariablesmanager.h \
       test/testformeditors.h \
       test/testmodels.h \
-      test/testcoreutils.h
+      test/testcoreutils.h \
+      test/testimageutils.h
 }
 
 contains(DEFINES, APPLE_PURCHASING) {

app/test/inputtests.cpp

@@ -25,6 +25,7 @@
 #include "test/testformeditors.h"
 #include "test/testmodels.h"
 #include "test/testcoreutils.h"
+#include "test/testimageutils.h"
 
 #if not defined APPLE_PURCHASING
 #include "test/testpurchasing.h"
@@ -160,6 +161,11 @@ int InputTests::runTest() const
     TestCoreUtils coreUtilsTest;
     nFailed = QTest::qExec( &coreUtilsTest, mTestArgs );
   }
+  else if ( mTestRequested == "--testImageUtils" )
+  {
+    TestImageUtils imageUtilsTest;
+    nFailed = QTest::qExec( &imageUtilsTest, mTestArgs );
+  }
 #if not defined APPLE_PURCHASING
   else if ( mTestRequested == "--testPurchasing" )
   {

app/test/testimageutils.cpp

@@ -0,0 +1,50 @@
+/***************************************************************************
+ *                                                                         *
+ *   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.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#include "testimageutils.h"
+#include "testutils.h"
+#include "imageutils.h"
+
+#include <QTemporaryDir>
+#include <QImage>
+#include <exiv2/exiv2.hpp>
+
+#include <QtTest/QtTest>
+
+void TestImageUtils::init()
+{
+}
+
+void TestImageUtils::cleanup()
+{
+}
+
+void TestImageUtils::testRescale()
+{
+  QTemporaryDir dir;
+  QString testPhotoName = QStringLiteral( "photo.jpg" );
+  QFile::copy( TestUtils::testDataDir() + '/' + testPhotoName, dir.filePath( testPhotoName ) );
+
+  QVERIFY( ImageUtils::rescale( dir.filePath( testPhotoName ), 3 ) );
+
+  QImage img( dir.filePath( testPhotoName ) );
+  QCOMPARE( img.height(), 800 );
+
+  // check EXIF tags
+  std::unique_ptr< Exiv2::Image > image( Exiv2::ImageFactory::open( dir.filePath( testPhotoName ).toStdString() ) );
+
+  image->readMetadata();
+  Exiv2::ExifData &exifData = image->exifData();
+  QVERIFY( !exifData.empty() );
+
+  const Exiv2::ExifData::iterator itElevVal = exifData.findKey( Exiv2::ExifKey( "Exif.GPSInfo.GPSAltitude" ) );
+  const Exiv2::Rational rational = itElevVal->value().toRational( 0 );
+  double val = static_cast< double >( rational.first ) / rational.second;
+  QCOMPARE( val, 133 );
+}

app/test/testimageutils.h

@@ -0,0 +1,26 @@
+/***************************************************************************
+ *                                                                         *
+ *   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.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#ifndef TESTIMAGEUTILS_H
+#define TESTIMAGEUTILS_H
+
+#include <QObject>
+
+class TestImageUtils : public QObject
+{
+    Q_OBJECT
+
+  private slots:
+    void init(); // will be called before each testfunction is executed.
+    void cleanup(); // will be called after every testfunction.
+
+    void testRescale();
+};
+
+#endif // TESTIMAGEUTILS_H

core/core.pri

@@ -12,7 +12,8 @@ SOURCES += \
   $$PWD/localprojectsmanager.cpp \
   $$PWD/merginprojectmetadata.cpp \
   $$PWD/project.cpp \
-  $$PWD/geodiffutils.cpp
+  $$PWD/geodiffutils.cpp \
+  $$PWD/imageutils.cpp
 
 HEADERS += \
   $$PWD/coreutils.h \
@@ -27,7 +28,8 @@ HEADERS += \
   $$PWD/localprojectsmanager.h \
   $$PWD/merginprojectmetadata.h \
   $$PWD/project.h \
-  $$PWD/geodiffutils.h
+  $$PWD/geodiffutils.h \
+  $$PWD/imageutils.h
 
 exists($$PWD/merginsecrets.cpp) {
   message("Using production Mergin API_KEYS")

core/imageutils.cpp

@@ -0,0 +1,131 @@
+/***************************************************************************
+ *                                                                         *
+ *   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.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#include "imageutils.h"
+
+#include "coreutils.h"
+
+#include <QFile>
+#include <QFileInfo>
+#include <QImage>
+
+#include <exiv2/exiv2.hpp>
+
+bool ImageUtils::copyExifMetadata( const QString &sourceImage, const QString &targetImage )
+{
+  if ( !QFileInfo::exists( sourceImage ) || !QFileInfo::exists( targetImage ) )
+    return false;
+
+  try
+  {
+    std::unique_ptr< Exiv2::Image > srcImage( Exiv2::ImageFactory::open( sourceImage.toStdString() ) );
+    if ( !srcImage )
+      return false;
+
+    std::unique_ptr< Exiv2::Image > dstImage( Exiv2::ImageFactory::open( targetImage.toStdString() ) );
+    if ( !dstImage )
+      return false;
+
+    srcImage->readMetadata();
+    Exiv2::ExifData &exifData = srcImage->exifData();
+    if ( exifData.empty() )
+    {
+      return true;
+    }
+
+    dstImage->setExifData( exifData );
+    dstImage->writeMetadata();
+    return true;
+  }
+  catch ( ... )
+  {
+    CoreUtils::log( "copying EXIF", QStringLiteral( "Failed to copy EXIF metadata" ) );
+    return false;
+  }
+}
+
+bool ImageUtils::rescale( const QString &path, int quality )
+{
+
+  QImage sourceImage( path );
+  bool isPortrait = sourceImage.height() > sourceImage.width();
+  int size = isPortrait ? sourceImage.width() : sourceImage.height();
+
+  int newSize = size;
+  switch ( quality )
+  {
+    case 0: // original quality, no rescaling needed
+    {
+      break;
+    }
+    case 1: // high quality, output image size ~5Mb
+    {
+      newSize = 3000;
+      break;
+    }
+    case 2: // medium quality, output image size ~3Mb
+    {
+      newSize = 1500;
+      break;
+    }
+    case 3: // low quality, output image size ~1Mb
+    {
+      newSize = 800;
+      break;
+    }
+  }
+
+  // if image width or height (depending on the orientation) is smaller
+  // than new size we keep original image
+  if ( size <= newSize )
+  {
+    return true;
+  }
+
+  // rescale
+  QImage rescaledImage;
+  if ( isPortrait )
+  {
+    rescaledImage = sourceImage.scaledToWidth( newSize, Qt::SmoothTransformation );
+  }
+  else
+  {
+    rescaledImage = sourceImage.scaledToHeight( newSize, Qt::SmoothTransformation );
+  }
+
+  if ( rescaledImage.isNull() )
+  {
+    CoreUtils::log( "rescaling image", QStringLiteral( "Failed to rescale %1" ).arg( path ) );
+    return false;
+  }
+
+  QFileInfo fi( path );
+  QString newPath = QStringLiteral( "%1/%2_rescaled.%3" ).arg( fi.path(), fi.baseName(), fi.completeSuffix() );
+
+  if ( !rescaledImage.save( newPath ) )
+  {
+    CoreUtils::log( "rescaling image", QStringLiteral( "Failed to save rescaled image" ) );
+    return false;
+  }
+
+  // copy EXIF from source image to rescaled image
+  copyExifMetadata( path, newPath );
+
+  // remove original file and rename rescaled version
+  if ( QFile::remove( path ) )
+  {
+    if ( QFile::rename( newPath, path ) )
+    {
+      return true;
+    }
+  }
+
+  CoreUtils::log( "rescaling image", QStringLiteral( "Can not replace original file with rescaled version" ) );
+  return false;
+}

core/imageutils.h

@@ -0,0 +1,33 @@
+/***************************************************************************
+ *                                                                         *
+ *   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.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#ifndef IMAGEUTILS_H
+#define IMAGEUTILS_H
+
+#include <QString>
+
+class ImageUtils
+{
+  public:
+    explicit ImageUtils( ) = default;
+    ~ImageUtils() = default;
+
+    /**
+     * Copies EXIF metadata from sourceImage to targetImage.
+     */
+    static bool copyExifMetadata( const QString &sourceImage, const QString &targetImage );
+
+    /**
+     * Rescales image to the given quality taking into account its orientation
+     * and preserving EXIF metadata.
+     */
+    static bool rescale( const QString &path, int quality );
+};
+
+#endif // IMAGEUTILS_H

scripts/run_all_tests.bash

@@ -51,6 +51,9 @@ NFAILURES=$(($NFAILURES+$?))
 $INPUT_EXECUTABLE --testCoreUtils
 NFAILURES=$(($NFAILURES+$?))
 
+$INPUT_EXECUTABLE --testImageUtils
+NFAILURES=$(($NFAILURES+$?))
+
 echo "Total $NFAILURES failures found in testing"
 
 exit $NFAILURES