14 files changed, 417 insertions, 242 deletions
diff --git a/src/gui/image/image.pri b/src/gui/image/image.pri
index 76aba944b2..b4942f06d4 100644
--- a/src/gui/image/image.pri
+++ b/src/gui/image/image.pri
@@ -9,6 +9,7 @@ HEADERS += \
         image/qimage_p.h \
         image/qimageiohandler.h \
         image/qimagereader.h \
+        image/qimagereaderwriterhelpers_p.h \
         image/qimagewriter.h \
         image/qpaintengine_pic_p.h \
         image/qpicture.h \
@@ -33,6 +34,7 @@ SOURCES += \
         image/qimage_conversions.cpp \
         image/qimageiohandler.cpp \
         image/qimagereader.cpp \
+        image/qimagereaderwriterhelpers.cpp \
         image/qimagewriter.cpp \
         image/qpaintengine_pic.cpp \
         image/qpicture.cpp \
diff --git a/src/gui/image/qbitmap.cpp b/src/gui/image/qbitmap.cpp
index e8405a6d11..2453242fa8 100644
--- a/src/gui/image/qbitmap.cpp
+++ b/src/gui/image/qbitmap.cpp
@@ -189,9 +189,7 @@ QBitmap &QBitmap::operator=(const QPixmap &pixmap)
     } else if (pixmap.depth() == 1) {                // 1-bit pixmap
         QPixmap::operator=(pixmap);                // shallow assignment
     } else {                                        // n-bit depth pixmap
-        QImage image;
-        image = pixmap.toImage();                                // convert pixmap to image
-        *this = fromImage(image);                                // will dither image
+        *this = fromImage(pixmap.toImage());        // will dither image
     }
     return *this;
 }
@@ -223,6 +221,24 @@ QBitmap::operator QVariant() const
     return QVariant(QVariant::Bitmap, this);
 }
 
+static QBitmap makeBitmap(QImage &&image, Qt::ImageConversionFlags flags)
+{
+    // make sure image.color(0) == Qt::color0 (white)
+    // and image.color(1) == Qt::color1 (black)
+    const QRgb c0 = QColor(Qt::black).rgb();
+    const QRgb c1 = QColor(Qt::white).rgb();
+    if (image.color(0) == c0 && image.color(1) == c1) {
+        image.invertPixels();
+        image.setColor(0, c1);
+        image.setColor(1, c0);
+    }
+
+    QScopedPointer<QPlatformPixmap> data(QGuiApplicationPrivate::platformIntegration()->createPlatformPixmap(QPlatformPixmap::BitmapType));
+
+    data->fromImageInPlace(image, flags | Qt::MonoOnly);
+    return QPixmap(data.take());
+}
+
 /*!
     Returns a copy of the given \a image converted to a bitmap using
     the specified image conversion \a flags.
@@ -234,22 +250,24 @@ QBitmap QBitmap::fromImage(const QImage &image, Qt::ImageConversionFlags flags)
     if (image.isNull())
         return QBitmap();
 
-    QImage img = image.convertToFormat(QImage::Format_MonoLSB, flags);
+    return makeBitmap(image.convertToFormat(QImage::Format_MonoLSB, flags), flags);
+}
 
-    // make sure image.color(0) == Qt::color0 (white)
-    // and image.color(1) == Qt::color1 (black)
-    const QRgb c0 = QColor(Qt::black).rgb();
-    const QRgb c1 = QColor(Qt::white).rgb();
-    if (img.color(0) == c0 && img.color(1) == c1) {
-        img.invertPixels();
-        img.setColor(0, c1);
-        img.setColor(1, c0);
-    }
+/*!
+    \since 5.12
+    \overload
 
-    QScopedPointer<QPlatformPixmap> data(QGuiApplicationPrivate::platformIntegration()->createPlatformPixmap(QPlatformPixmap::BitmapType));
+    Returns a copy of the given \a image converted to a bitmap using
+    the specified image conversion \a flags.
 
-    data->fromImage(img, flags | Qt::MonoOnly);
-    return QPixmap(data.take());
+    \sa fromData()
+*/
+QBitmap QBitmap::fromImage(QImage &&image, Qt::ImageConversionFlags flags)
+{
+    if (image.isNull())
+        return QBitmap();
+
+    return makeBitmap(std::move(image).convertToFormat(QImage::Format_MonoLSB, flags), flags);
 }
 
 /*!
@@ -277,7 +295,7 @@ QBitmap QBitmap::fromData(const QSize &size, const uchar *bits, QImage::Format m
     int bytesPerLine = (size.width() + 7) / 8;
     for (int y = 0; y < size.height(); ++y)
         memcpy(image.scanLine(y), bits + bytesPerLine * y, bytesPerLine);
-    return QBitmap::fromImage(image);
+    return QBitmap::fromImage(std::move(image));
 }
 
 /*!
diff --git a/src/gui/image/qbitmap.h b/src/gui/image/qbitmap.h
index 6a8c8b3457..188064fccf 100644
--- a/src/gui/image/qbitmap.h
+++ b/src/gui/image/qbitmap.h
@@ -72,6 +72,7 @@ public:
     inline void clear() { fill(Qt::color0); }
 
     static QBitmap fromImage(const QImage &image, Qt::ImageConversionFlags flags = Qt::AutoColor);
+    static QBitmap fromImage(QImage &&image, Qt::ImageConversionFlags flags = Qt::AutoColor);
     static QBitmap fromData(const QSize &size, const uchar *bits,
                             QImage::Format monoFormat = QImage::Format_MonoLSB);
 
diff --git a/src/gui/image/qimage.cpp b/src/gui/image/qimage.cpp
index 7fcae12cbd..469ae8b97e 100644
--- a/src/gui/image/qimage.cpp
+++ b/src/gui/image/qimage.cpp
@@ -2582,15 +2582,14 @@ bool QImage::allGray() const
         break;
     }
 
-    const int buffer_size = 2048;
-    uint buffer[buffer_size];
+    uint buffer[BufferSize];
     const QPixelLayout *layout = &qPixelLayouts[d->format];
     FetchPixelsFunc fetch = qFetchPixels[layout->bpp];
     for (int j = 0; j < d->height; ++j) {
         const uchar *b = constScanLine(j);
         int x = 0;
         while (x < d->width) {
-            int l = qMin(d->width - x, buffer_size);
+            int l = qMin(d->width - x, BufferSize);
             const uint *ptr = fetch(buffer, b, x, l);
             ptr = layout->convertToARGB32PM(buffer, ptr, l, 0, 0);
             for (int i = 0; i < l; ++i) {
@@ -3218,14 +3217,13 @@ inline void rgbSwapped_generic(int width, int height, const QImage *src, QImage
     const uint alphaGreenMask = (((1 << layout->alphaWidth) - 1) << layout->alphaShift)
             | (((1 << layout->greenWidth) - 1) << layout->greenShift);
 
-    const int buffer_size = 2048;
-    uint buffer[buffer_size];
+    uint buffer[BufferSize];
     for (int i = 0; i < height; ++i) {
         uchar *q = dst->scanLine(i);
         const uchar *p = src->constScanLine(i);
         int x = 0;
         while (x < width) {
-            int l = qMin(width - x, buffer_size);
+            int l = qMin(width - x, BufferSize);
             const uint *ptr = fetch(buffer, p, x, l);
             for (int j = 0; j < l; ++j) {
                 uint red = (ptr[j] >> layout->redShift) & redBlueMask;
@@ -3457,8 +3455,7 @@ void QImage::rgbSwapped_inplace()
 
 bool QImage::load(const QString &fileName, const char* format)
 {
-    QImage image = QImageReader(fileName, format).read();
-    operator=(image);
+    *this = QImageReader(fileName, format).read();
     return !isNull();
 }
 
@@ -3471,8 +3468,7 @@ bool QImage::load(const QString &fileName, const char* format)
 
 bool QImage::load(QIODevice* device, const char* format)
 {
-    QImage image = QImageReader(device, format).read();
-    operator=(image);
+    *this = QImageReader(device, format).read();
     return !isNull();
 }
 
@@ -3492,8 +3488,7 @@ bool QImage::load(QIODevice* device, const char* format)
 
 bool QImage::loadFromData(const uchar *data, int len, const char *format)
 {
-    QImage image = fromData(data, len, format);
-    operator=(image);
+    *this = fromData(data, len, format);
     return !isNull();
 }
 
diff --git a/src/gui/image/qimage_conversions.cpp b/src/gui/image/qimage_conversions.cpp
index 4eef617336..9a8cbf43c9 100644
--- a/src/gui/image/qimage_conversions.cpp
+++ b/src/gui/image/qimage_conversions.cpp
@@ -145,8 +145,7 @@ void convert_generic(QImageData *dest, const QImageData *src, Qt::ImageConversio
     // Cannot be used with indexed formats.
     Q_ASSERT(dest->format > QImage::Format_Indexed8);
     Q_ASSERT(src->format > QImage::Format_Indexed8);
-    const int buffer_size = 2048;
-    uint buf[buffer_size];
+    uint buf[BufferSize];
     uint *buffer = buf;
     const QPixelLayout *srcLayout = &qPixelLayouts[src->format];
     const QPixelLayout *destLayout = &qPixelLayouts[dest->format];
@@ -196,7 +195,7 @@ void convert_generic(QImageData *dest, const QImageData *src, Qt::ImageConversio
             if (destLayout->bpp == QPixelLayout::BPP32)
                 buffer = reinterpret_cast<uint *>(destData) + x;
             else
-                l = qMin(l, buffer_size);
+                l = qMin(l, BufferSize);
             const uint *ptr = fetch(buffer, srcData, x, l);
             ptr = convertToARGB32PM(buffer, ptr, l, 0, ditherPtr);
             ptr = convertFromARGB32PM(buffer, ptr, l, 0, ditherPtr);
@@ -217,8 +216,7 @@ bool convert_generic_inplace(QImageData *data, QImage::Format dst_format, Qt::Im
     if (data->depth != qt_depthForFormat(dst_format))
         return false;
 
-    const int buffer_size = 2048;
-    uint buffer[buffer_size];
+    uint buffer[BufferSize];
     const QPixelLayout *srcLayout = &qPixelLayouts[data->format];
     const QPixelLayout *destLayout = &qPixelLayouts[dst_format];
     uchar *srcData = data->data;
@@ -261,7 +259,7 @@ bool convert_generic_inplace(QImageData *data, QImage::Format dst_format, Qt::Im
         int x = 0;
         while (x < data->width) {
             dither.x = x;
-            int l = qMin(data->width - x, buffer_size);
+            int l = qMin(data->width - x, BufferSize);
             const uint *ptr = fetch(buffer, srcData, x, l);
             ptr = convertToARGB32PM(buffer, ptr, l, 0, ditherPtr);
             ptr = convertFromARGB32PM(buffer, ptr, l, 0, ditherPtr);
diff --git a/src/gui/image/qimagereader.cpp b/src/gui/image/qimagereader.cpp
index 7086e102ea..e77c6f019c 100644
--- a/src/gui/image/qimagereader.cpp
+++ b/src/gui/image/qimagereader.cpp
@@ -164,73 +164,13 @@
 #include <private/qpnghandler_p.h>
 #endif
 
+#include <private/qimagereaderwriterhelpers_p.h>
+
 #include <algorithm>
 
 QT_BEGIN_NAMESPACE
 
-#ifndef QT_NO_IMAGEFORMATPLUGIN
-Q_GLOBAL_STATIC_WITH_ARGS(QFactoryLoader, loader,
-                          (QImageIOHandlerFactoryInterface_iid, QLatin1String("/imageformats")))
-#endif
-
-enum _qt_BuiltInFormatType {
-#ifndef QT_NO_IMAGEFORMAT_PNG
-    _qt_PngFormat,
-#endif
-#ifndef QT_NO_IMAGEFORMAT_BMP
-    _qt_BmpFormat,
-#endif
-#ifndef QT_NO_IMAGEFORMAT_PPM
-    _qt_PpmFormat,
-    _qt_PgmFormat,
-    _qt_PbmFormat,
-#endif
-#ifndef QT_NO_IMAGEFORMAT_XBM
-    _qt_XbmFormat,
-#endif
-#ifndef QT_NO_IMAGEFORMAT_XPM
-    _qt_XpmFormat,
-#endif
-    _qt_NumFormats,
-    _qt_NoFormat = -1
-};
-
-#if !defined(QT_NO_IMAGEFORMAT_PPM)
-# define MAX_MT_SIZE 20
-#elif !defined(QT_NO_IMAGEFORMAT_XBM) || !defined(QT_NO_IMAGEFORMAT_XPM)
-#  define MAX_MT_SIZE 10
-#else
-#  define MAX_MT_SIZE 4
-#endif
-
-struct _qt_BuiltInFormatStruct
-{
-    char extension[4];
-    char mimeType[MAX_MT_SIZE];
-};
-
-#undef MAX_MT_SIZE
-
-static const _qt_BuiltInFormatStruct _qt_BuiltInFormats[] = {
-#ifndef QT_NO_IMAGEFORMAT_PNG
-    {"png", "png"},
-#endif
-#ifndef QT_NO_IMAGEFORMAT_BMP
-    {"bmp", "bmp"},
-#endif
-#ifndef QT_NO_IMAGEFORMAT_PPM
-    {"ppm", "x-portable-pixmap"},
-    {"pgm", "x-portable-graymap"},
-    {"pbm", "x-portable-bitmap"},
-#endif
-#ifndef QT_NO_IMAGEFORMAT_XBM
-    {"xbm", "x-xbitmap"},
-#endif
-#ifndef QT_NO_IMAGEFORMAT_XPM
-    {"xpm", "x-xpixmap"},
-#endif
-};
-Q_STATIC_ASSERT(_qt_NumFormats == sizeof _qt_BuiltInFormats / sizeof *_qt_BuiltInFormats);
+using namespace QImageReaderWriterHelpers;
 
 static QImageIOHandler *createReadHandlerHelper(QIODevice *device,
                                                 const QByteArray &format,
@@ -251,7 +191,7 @@ static QImageIOHandler *createReadHandlerHelper(QIODevice *device,
     typedef QMultiMap<int, QString> PluginKeyMap;
 
     // check if we have plugins that support the image format
-    QFactoryLoader *l = loader();
+    auto l = QImageReaderWriterHelpers::pluginLoader();
     const PluginKeyMap keyMap = l->keyMap();
 
 #ifdef QIMAGEREADER_DEBUG
@@ -1565,16 +1505,6 @@ QByteArray QImageReader::imageFormat(QIODevice *device)
     return format;
 }
 
-#ifndef QT_NO_IMAGEFORMATPLUGIN
-void supportedImageHandlerFormats(QFactoryLoader *loader,
-                                  QImageIOPlugin::Capability cap,
-                                  QList<QByteArray> *result);
-
-void supportedImageHandlerMimeTypes(QFactoryLoader *loader,
-                                  QImageIOPlugin::Capability cap,
-                                  QList<QByteArray> *result);
-#endif
-
 /*!
     Returns the list of image formats supported by QImageReader.
 
@@ -1605,18 +1535,7 @@ void supportedImageHandlerMimeTypes(QFactoryLoader *loader,
 
 QList<QByteArray> QImageReader::supportedImageFormats()
 {
-    QList<QByteArray> formats;
-    formats.reserve(_qt_NumFormats);
-    for (int i = 0; i < _qt_NumFormats; ++i)
-        formats << _qt_BuiltInFormats[i].extension;
-
-#ifndef QT_NO_IMAGEFORMATPLUGIN
-    supportedImageHandlerFormats(loader(), QImageIOPlugin::CanRead, &formats);
-#endif // QT_NO_IMAGEFORMATPLUGIN
-
-    std::sort(formats.begin(), formats.end());
-    formats.erase(std::unique(formats.begin(), formats.end()), formats.end());
-    return formats;
+    return QImageReaderWriterHelpers::supportedImageFormats(QImageReaderWriterHelpers::CanRead);
 }
 
 /*!
@@ -1630,18 +1549,24 @@ QList<QByteArray> QImageReader::supportedImageFormats()
 
 QList<QByteArray> QImageReader::supportedMimeTypes()
 {
-    QList<QByteArray> mimeTypes;
-    mimeTypes.reserve(_qt_NumFormats);
-    for (const auto &fmt : _qt_BuiltInFormats)
-        mimeTypes.append(QByteArrayLiteral("image/") + fmt.mimeType);
+    return QImageReaderWriterHelpers::supportedMimeTypes(QImageReaderWriterHelpers::CanRead);
+}
 
-#ifndef QT_NO_IMAGEFORMATPLUGIN
-    supportedImageHandlerMimeTypes(loader(), QImageIOPlugin::CanRead, &mimeTypes);
-#endif // QT_NO_IMAGEFORMATPLUGIN
+/*!
+    \since 5.12
 
-    std::sort(mimeTypes.begin(), mimeTypes.end());
-    mimeTypes.erase(std::unique(mimeTypes.begin(), mimeTypes.end()), mimeTypes.end());
-    return mimeTypes;
+    Returns the list of image formats corresponding to \mimeType.
+
+    Note that the QGuiApplication instance must be created before this function is
+    called.
+
+    \sa supportedImageFormats(), supportedMimeTypes()
+*/
+
+QList<QByteArray> QImageReader::imageFormatsForMimeType(const QByteArray &mimeType)
+{
+    return QImageReaderWriterHelpers::imageFormatsForMimeType(mimeType,
+                                                              QImageReaderWriterHelpers::CanRead);
 }
 
 QT_END_NAMESPACE
diff --git a/src/gui/image/qimagereader.h b/src/gui/image/qimagereader.h
index 9d6c1e0b1e..4e9a08b6e6 100644
--- a/src/gui/image/qimagereader.h
+++ b/src/gui/image/qimagereader.h
@@ -144,6 +144,7 @@ public:
     static QByteArray imageFormat(QIODevice *device);
     static QList<QByteArray> supportedImageFormats();
     static QList<QByteArray> supportedMimeTypes();
+    static QList<QByteArray> imageFormatsForMimeType(const QByteArray &mimeType);
 
 private:
     Q_DISABLE_COPY(QImageReader)
diff --git a/src/gui/image/qimagereaderwriterhelpers.cpp b/src/gui/image/qimagereaderwriterhelpers.cpp
new file mode 100644
index 0000000000..a5b7fb6449
--- /dev/null
+++ b/src/gui/image/qimagereaderwriterhelpers.cpp
@@ -0,0 +1,180 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "private/qimagereaderwriterhelpers_p.h"
+
+#include <qjsonarray.h>
+#include <qmutex.h>
+#include <private/qfactoryloader_p.h>
+
+QT_BEGIN_NAMESPACE
+
+namespace QImageReaderWriterHelpers {
+
+#ifndef QT_NO_IMAGEFORMATPLUGIN
+
+Q_GLOBAL_STATIC_WITH_ARGS(QFactoryLoader, loader,
+                          (QImageIOHandlerFactoryInterface_iid, QLatin1String("/imageformats")))
+Q_GLOBAL_STATIC(QMutex, loaderMutex)
+
+static void appendImagePluginFormats(QFactoryLoader *loader,
+                                     QImageIOPlugin::Capability cap,
+                                     QList<QByteArray> *result)
+{
+    typedef QMultiMap<int, QString> PluginKeyMap;
+    typedef PluginKeyMap::const_iterator PluginKeyMapConstIterator;
+
+    const PluginKeyMap keyMap = loader->keyMap();
+    const PluginKeyMapConstIterator cend = keyMap.constEnd();
+    int i = -1;
+    QImageIOPlugin *plugin = 0;
+    result->reserve(result->size() + keyMap.size());
+    for (PluginKeyMapConstIterator it = keyMap.constBegin(); it != cend; ++it) {
+        if (it.key() != i) {
+            i = it.key();
+            plugin = qobject_cast<QImageIOPlugin *>(loader->instance(i));
+        }
+        const QByteArray key = it.value().toLatin1();
+        if (plugin && (plugin->capabilities(0, key) & cap) != 0)
+            result->append(key);
+    }
+}
+
+static void appendImagePluginMimeTypes(QFactoryLoader *loader,
+                                       QImageIOPlugin::Capability cap,
+                                       QList<QByteArray> *result,
+                                       QList<QByteArray> *resultKeys = nullptr)
+{
+    QList<QJsonObject> metaDataList = loader->metaData();
+
+    const int pluginCount = metaDataList.size();
+    for (int i = 0; i < pluginCount; ++i) {
+        const QJsonObject metaData = metaDataList.at(i).value(QLatin1String("MetaData")).toObject();
+        const QJsonArray keys = metaData.value(QLatin1String("Keys")).toArray();
+        const QJsonArray mimeTypes = metaData.value(QLatin1String("MimeTypes")).toArray();
+        QImageIOPlugin *plugin = qobject_cast<QImageIOPlugin *>(loader->instance(i));
+        const int keyCount = keys.size();
+        for (int k = 0; k < keyCount; ++k) {
+            const QByteArray key = keys.at(k).toString().toLatin1();
+            if (plugin && (plugin->capabilities(0, key) & cap) != 0) {
+                result->append(mimeTypes.at(k).toString().toLatin1());
+                if (resultKeys)
+                    resultKeys->append(key);
+            }
+        }
+    }
+}
+
+QSharedPointer<QFactoryLoader> pluginLoader()
+{
+    loaderMutex()->lock();
+    return QSharedPointer<QFactoryLoader>(loader(), [](QFactoryLoader *) {
+        loaderMutex()->unlock();
+    });
+}
+
+static inline QImageIOPlugin::Capability pluginCapability(Capability cap)
+{
+    return cap == CanRead ? QImageIOPlugin::CanRead : QImageIOPlugin::CanWrite;
+}
+
+#endif // QT_NO_IMAGEFORMATPLUGIN
+
+QList<QByteArray> supportedImageFormats(Capability cap)
+{
+    QList<QByteArray> formats;
+    formats.reserve(_qt_NumFormats);
+    for (int i = 0; i < _qt_NumFormats; ++i)
+        formats << _qt_BuiltInFormats[i].extension;
+
+#ifndef QT_NO_IMAGEFORMATPLUGIN
+    appendImagePluginFormats(loader(), pluginCapability(cap), &formats);
+#endif // QT_NO_IMAGEFORMATPLUGIN
+
+    std::sort(formats.begin(), formats.end());
+    formats.erase(std::unique(formats.begin(), formats.end()), formats.end());
+    return formats;
+}
+
+QList<QByteArray> supportedMimeTypes(Capability cap)
+{
+    QList<QByteArray> mimeTypes;
+    mimeTypes.reserve(_qt_NumFormats);
+    for (const auto &fmt : _qt_BuiltInFormats)
+        mimeTypes.append(QByteArrayLiteral("image/") + fmt.mimeType);
+
+#ifndef QT_NO_IMAGEFORMATPLUGIN
+    appendImagePluginMimeTypes(loader(), pluginCapability(cap), &mimeTypes);
+#endif // QT_NO_IMAGEFORMATPLUGIN
+
+    std::sort(mimeTypes.begin(), mimeTypes.end());
+    mimeTypes.erase(std::unique(mimeTypes.begin(), mimeTypes.end()), mimeTypes.end());
+    return mimeTypes;
+}
+
+QList<QByteArray> imageFormatsForMimeType(const QByteArray &mimeType, Capability cap)
+{
+    QList<QByteArray> formats;
+    if (mimeType.startsWith("image/")) {
+        const QByteArray type = mimeType.mid(sizeof("image/") - 1);
+        for (const auto &fmt : _qt_BuiltInFormats) {
+            if (fmt.mimeType == type && !formats.contains(fmt.extension))
+                formats << fmt.extension;
+        }
+    }
+
+#ifndef QT_NO_IMAGEFORMATPLUGIN
+    QList<QByteArray> mimeTypes;
+    QList<QByteArray> keys;
+    appendImagePluginMimeTypes(loader(), pluginCapability(cap), &mimeTypes, &keys);
+    for (int i = 0; i < mimeTypes.size(); ++i) {
+        if (mimeTypes.at(i) == mimeType) {
+            const auto &key = keys.at(i);
+            if (!formats.contains(key))
+                formats << key;
+        }
+    }
+#endif // QT_NO_IMAGEFORMATPLUGIN
+
+    return formats;
+}
+
+} // QImageReaderWriterHelpers
+
+QT_END_NAMESPACE
diff --git a/src/gui/image/qimagereaderwriterhelpers_p.h b/src/gui/image/qimagereaderwriterhelpers_p.h
new file mode 100644
index 0000000000..6fe418a8ab
--- /dev/null
+++ b/src/gui/image/qimagereaderwriterhelpers_p.h
@@ -0,0 +1,139 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QIMAGEREADERWRITERHELPERS_P_H
+#define QIMAGEREADERWRITERHELPERS_P_H
+
+#include <QtGui/private/qtguiglobal_p.h>
+#include <qsharedpointer.h>
+#include "qimageiohandler.h"
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API. It exists purely as an
+// implementation detail. This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+QT_BEGIN_NAMESPACE
+
+class QFactoryLoader;
+
+namespace QImageReaderWriterHelpers {
+
+enum _qt_BuiltInFormatType {
+#ifndef QT_NO_IMAGEFORMAT_PNG
+    _qt_PngFormat,
+#endif
+#ifndef QT_NO_IMAGEFORMAT_BMP
+    _qt_BmpFormat,
+#endif
+#ifndef QT_NO_IMAGEFORMAT_PPM
+    _qt_PpmFormat,
+    _qt_PgmFormat,
+    _qt_PbmFormat,
+#endif
+#ifndef QT_NO_IMAGEFORMAT_XBM
+    _qt_XbmFormat,
+#endif
+#ifndef QT_NO_IMAGEFORMAT_XPM
+    _qt_XpmFormat,
+#endif
+    _qt_NumFormats,
+    _qt_NoFormat = -1
+};
+
+#if !defined(QT_NO_IMAGEFORMAT_PPM)
+# define MAX_MT_SIZE 20
+#elif !defined(QT_NO_IMAGEFORMAT_XBM) || !defined(QT_NO_IMAGEFORMAT_XPM)
+#  define MAX_MT_SIZE 10
+#else
+#  define MAX_MT_SIZE 4
+#endif
+
+struct _qt_BuiltInFormatStruct
+{
+    char extension[4];
+    char mimeType[MAX_MT_SIZE];
+};
+
+#undef MAX_MT_SIZE
+
+static const _qt_BuiltInFormatStruct _qt_BuiltInFormats[] = {
+#ifndef QT_NO_IMAGEFORMAT_PNG
+    {"png", "png"},
+#endif
+#ifndef QT_NO_IMAGEFORMAT_BMP
+    {"bmp", "bmp"},
+#endif
+#ifndef QT_NO_IMAGEFORMAT_PPM
+    {"ppm", "x-portable-pixmap"},
+    {"pgm", "x-portable-graymap"},
+    {"pbm", "x-portable-bitmap"},
+#endif
+#ifndef QT_NO_IMAGEFORMAT_XBM
+    {"xbm", "x-xbitmap"},
+#endif
+#ifndef QT_NO_IMAGEFORMAT_XPM
+    {"xpm", "x-xpixmap"},
+#endif
+};
+Q_STATIC_ASSERT(_qt_NumFormats == sizeof _qt_BuiltInFormats / sizeof *_qt_BuiltInFormats);
+
+#ifndef QT_NO_IMAGEFORMATPLUGIN
+QSharedPointer<QFactoryLoader> pluginLoader();
+#endif
+
+enum Capability {
+    CanRead,
+    CanWrite
+};
+QList<QByteArray> supportedImageFormats(Capability cap);
+QList<QByteArray> supportedMimeTypes(Capability cap);
+QList<QByteArray> imageFormatsForMimeType(const QByteArray &mimeType, Capability cap);
+
+}
+
+QT_END_NAMESPACE
+
+#endif // QIMAGEREADERWRITERHELPERS_P_H
diff --git a/src/gui/image/qimagewriter.cpp b/src/gui/image/qimagewriter.cpp
index a39d204677..30ec224158 100644
--- a/src/gui/image/qimagewriter.cpp
+++ b/src/gui/image/qimagewriter.cpp
@@ -102,7 +102,6 @@
 #include <qfileinfo.h>
 #include <qimage.h>
 #include <qimageiohandler.h>
-#include <qjsonarray.h>
 #include <qset.h>
 #include <qvariant.h>
 
@@ -119,15 +118,12 @@
 #include <private/qpnghandler_p.h>
 #endif
 
+#include <private/qimagereaderwriterhelpers_p.h>
+
 #include <algorithm>
 
 QT_BEGIN_NAMESPACE
 
-#ifndef QT_NO_IMAGEFORMATPLUGIN
-Q_GLOBAL_STATIC_WITH_ARGS(QFactoryLoader, loader,
-                          (QImageIOHandlerFactoryInterface_iid, QLatin1String("/imageformats")))
-#endif
-
 static QImageIOHandler *createWriteHandlerHelper(QIODevice *device,
     const QByteArray &format)
 {
@@ -139,7 +135,7 @@ static QImageIOHandler *createWriteHandlerHelper(QIODevice *device,
     typedef QMultiMap<int, QString> PluginKeyMap;
 
     // check if any plugins can write the image
-    QFactoryLoader *l = loader();
+    auto l = QImageReaderWriterHelpers::pluginLoader();
     const PluginKeyMap keyMap = l->keyMap();
     int suffixPluginIndex = -1;
 #endif
@@ -824,52 +820,6 @@ bool QImageWriter::supportsOption(QImageIOHandler::ImageOption option) const
     return d->handler->supportsOption(option);
 }
 
-
-#ifndef QT_NO_IMAGEFORMATPLUGIN
-void supportedImageHandlerFormats(QFactoryLoader *loader,
-                                  QImageIOPlugin::Capability cap,
-                                  QList<QByteArray> *result)
-{
-    typedef QMultiMap<int, QString> PluginKeyMap;
-    typedef PluginKeyMap::const_iterator PluginKeyMapConstIterator;
-
-    const PluginKeyMap keyMap = loader->keyMap();
-    const PluginKeyMapConstIterator cend = keyMap.constEnd();
-    int i = -1;
-    QImageIOPlugin *plugin = 0;
-    result->reserve(result->size() + keyMap.size());
-    for (PluginKeyMapConstIterator it = keyMap.constBegin(); it != cend; ++it) {
-        if (it.key() != i) {
-            i = it.key();
-            plugin = qobject_cast<QImageIOPlugin *>(loader->instance(i));
-        }
-        const QByteArray key = it.value().toLatin1();
-        if (plugin && (plugin->capabilities(0, key) & cap) != 0)
-            result->append(key);
-    }
-}
-
-void supportedImageHandlerMimeTypes(QFactoryLoader *loader,
-                                    QImageIOPlugin::Capability cap,
-                                    QList<QByteArray> *result)
-{
-    QList<QJsonObject> metaDataList = loader->metaData();
-
-    const int pluginCount = metaDataList.size();
-    for (int i = 0; i < pluginCount; ++i) {
-        const QJsonObject metaData = metaDataList.at(i).value(QLatin1String("MetaData")).toObject();
-        const QJsonArray keys = metaData.value(QLatin1String("Keys")).toArray();
-        const QJsonArray mimeTypes = metaData.value(QLatin1String("MimeTypes")).toArray();
-        QImageIOPlugin *plugin = qobject_cast<QImageIOPlugin *>(loader->instance(i));
-        const int keyCount = keys.size();
-        for (int k = 0; k < keyCount; ++k) {
-            if (plugin && (plugin->capabilities(0, keys.at(k).toString().toLatin1()) & cap) != 0)
-                result->append(mimeTypes.at(k).toString().toLatin1());
-        }
-    }
-}
-#endif // QT_NO_IMAGEFORMATPLUGIN
-
 /*!
     Returns the list of image formats supported by QImageWriter.
 
@@ -897,30 +847,7 @@ void supportedImageHandlerMimeTypes(QFactoryLoader *loader,
 */
 QList<QByteArray> QImageWriter::supportedImageFormats()
 {
-    QList<QByteArray> formats;
-#ifndef QT_NO_IMAGEFORMAT_BMP
-    formats << "bmp";
-#endif
-#ifndef QT_NO_IMAGEFORMAT_PPM
-    formats << "pbm" << "pgm" << "ppm";
-#endif
-#ifndef QT_NO_IMAGEFORMAT_XBM
-    formats << "xbm";
-#endif
-#ifndef QT_NO_IMAGEFORMAT_XPM
-    formats << "xpm";
-#endif
-#ifndef QT_NO_IMAGEFORMAT_PNG
-    formats << "png";
-#endif
-
-#ifndef QT_NO_IMAGEFORMATPLUGIN
-    supportedImageHandlerFormats(loader(), QImageIOPlugin::CanWrite, &formats);
-#endif // QT_NO_IMAGEFORMATPLUGIN
-
-    std::sort(formats.begin(), formats.end());
-    formats.erase(std::unique(formats.begin(), formats.end()), formats.end());
-    return formats;
+    return QImageReaderWriterHelpers::supportedImageFormats(QImageReaderWriterHelpers::CanWrite);
 }
 
 /*!
@@ -933,32 +860,24 @@ QList<QByteArray> QImageWriter::supportedImageFormats()
 */
 QList<QByteArray> QImageWriter::supportedMimeTypes()
 {
-    QList<QByteArray> mimeTypes;
-#ifndef QT_NO_IMAGEFORMAT_BMP
-    mimeTypes << "image/bmp";
-#endif
-#ifndef QT_NO_IMAGEFORMAT_PPM
-    mimeTypes << "image/x-portable-bitmap";
-    mimeTypes << "image/x-portable-graymap";
-    mimeTypes << "image/x-portable-pixmap";
-#endif
-#ifndef QT_NO_IMAGEFORMAT_XBM
-    mimeTypes << "image/x-xbitmap";
-#endif
-#ifndef QT_NO_IMAGEFORMAT_XPM
-    mimeTypes << "image/x-xpixmap";
-#endif
-#ifndef QT_NO_IMAGEFORMAT_PNG
-    mimeTypes << "image/png";
-#endif
+    return QImageReaderWriterHelpers::supportedMimeTypes(QImageReaderWriterHelpers::CanWrite);
+}
 
-#ifndef QT_NO_IMAGEFORMATPLUGIN
-    supportedImageHandlerMimeTypes(loader(), QImageIOPlugin::CanWrite, &mimeTypes);
-#endif // QT_NO_IMAGEFORMATPLUGIN
+/*!
+    \since 5.12
 
-    std::sort(mimeTypes.begin(), mimeTypes.end());
-    mimeTypes.erase(std::unique(mimeTypes.begin(), mimeTypes.end()), mimeTypes.end());
-    return mimeTypes;
+    Returns the list of image formats corresponding to \mimeType.
+
+    Note that the QGuiApplication instance must be created before this function is
+    called.
+
+    \sa supportedImageFormats(), supportedMimeTypes()
+*/
+
+QList<QByteArray> QImageWriter::imageFormatsForMimeType(const QByteArray &mimeType)
+{
+    return QImageReaderWriterHelpers::imageFormatsForMimeType(mimeType,
+                                                              QImageReaderWriterHelpers::CanWrite);
 }
 
 QT_END_NAMESPACE
diff --git a/src/gui/image/qimagewriter.h b/src/gui/image/qimagewriter.h
index fd1fdd07e8..29c06ccdd2 100644
--- a/src/gui/image/qimagewriter.h
+++ b/src/gui/image/qimagewriter.h
@@ -116,6 +116,7 @@ public:
 
     static QList<QByteArray> supportedImageFormats();
     static QList<QByteArray> supportedMimeTypes();
+    static QList<QByteArray> imageFormatsForMimeType(const QByteArray &mimeType);
 
 private:
     Q_DISABLE_COPY(QImageWriter)
diff --git a/src/gui/image/qpixmap.cpp b/src/gui/image/qpixmap.cpp
index 5b3e3985a7..4cd8befc1b 100644
--- a/src/gui/image/qpixmap.cpp
+++ b/src/gui/image/qpixmap.cpp
@@ -248,9 +248,9 @@ QPixmap::QPixmap(const char * const xpm[])
     QImage image(xpm);
     if (!image.isNull()) {
         if (data && data->pixelType() == QPlatformPixmap::BitmapType)
-            *this = QBitmap::fromImage(image);
+            *this = QBitmap::fromImage(std::move(image));
         else
-            *this = fromImage(image);
+            *this = fromImage(std::move(image));
     }
 }
 #endif
@@ -691,7 +691,7 @@ QBitmap QPixmap::createHeuristicMask(bool clipTight) const
 QBitmap QPixmap::createMaskFromColor(const QColor &maskColor, Qt::MaskMode mode) const
 {
     QImage image = toImage().convertToFormat(QImage::Format_ARGB32);
-    return QBitmap::fromImage(image.createMaskFromColor(maskColor.rgba(), mode));
+    return QBitmap::fromImage(std::move(image).createMaskFromColor(maskColor.rgba(), mode));
 }
 
 /*!
@@ -1018,9 +1018,9 @@ QDataStream &operator>>(QDataStream &stream, QPixmap &pixmap)
     if (image.isNull()) {
         pixmap = QPixmap();
     } else if (image.depth() == 1) {
-        pixmap = QBitmap::fromImage(image);
+        pixmap = QBitmap::fromImage(std::move(image));
     } else {
-        pixmap = QPixmap::fromImage(image);
+        pixmap = QPixmap::fromImage(std::move(image));
     }
     return stream;
 }
diff --git a/src/gui/image/qxbmhandler.cpp b/src/gui/image/qxbmhandler.cpp
index 155a4f88b4..24d86e116d 100644
--- a/src/gui/image/qxbmhandler.cpp
+++ b/src/gui/image/qxbmhandler.cpp
@@ -241,7 +241,7 @@ static bool write_xbm_image(const QImage &sourceImage, QIODevice *device, const
             }
         }
     }
-#if defined(_MSC_VER) && _MSC_VER >= 1400
+#ifdef Q_CC_MSVC
     strcpy_s(p, sizeof(" };\n"), " };\n");
 #else
     strcpy(p, " };\n");
diff --git a/src/gui/image/qxpmhandler.cpp b/src/gui/image/qxpmhandler.cpp
index 9c54b9ada4..17272ffe69 100644
--- a/src/gui/image/qxpmhandler.cpp
+++ b/src/gui/image/qxpmhandler.cpp
@@ -741,10 +741,6 @@ static const struct XPMRGBData {
   { QRGB(139,139,  0),  "yellow4" },
   { QRGB(154,205, 50),  "yellowgreen" } };
 
-#if defined(Q_CC_MSVC) && _MSC_VER < 1600
-inline bool operator<(const XPMRGBData &data1, const XPMRGBData &data2)
-{ return qstrcmp(data1.name, data2.name) < 0; }
-#endif
 
 inline bool operator<(const char *name, const XPMRGBData &data)
 { return qstrcmp(name, data.name) < 0; }