16 files changed, 205 insertions, 673 deletions
diff --git a/src/plugins/imageformats/CMakeLists.txt b/src/plugins/imageformats/CMakeLists.txt
index 00fefbdc0d..c5ab716d00 100644
--- a/src/plugins/imageformats/CMakeLists.txt
+++ b/src/plugins/imageformats/CMakeLists.txt
@@ -1,4 +1,5 @@
-# Generated from imageformats.pro.
+# Copyright (C) 2022 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
 
 if(QT_FEATURE_ico)
     add_subdirectory(ico)
diff --git a/src/plugins/imageformats/gif/CMakeLists.txt b/src/plugins/imageformats/gif/CMakeLists.txt
index 1ffd702f85..b56859a264 100644
--- a/src/plugins/imageformats/gif/CMakeLists.txt
+++ b/src/plugins/imageformats/gif/CMakeLists.txt
@@ -1,4 +1,5 @@
-# Generated from gif.pro.
+# Copyright (C) 2022 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
 
 #####################################################################
 ## QGifPlugin Plugin:
@@ -6,14 +7,11 @@
 
 qt_internal_add_plugin(QGifPlugin
     OUTPUT_NAME qgif
-    TYPE imageformats
+    PLUGIN_TYPE imageformats
     SOURCES
-        main.cpp main.h
+        main.cpp
         qgifhandler.cpp qgifhandler_p.h
-    LIBRARIES # special case
-        Qt::Gui # special case
-        Qt::GuiPrivate # special case
+    LIBRARIES
+        Qt::Gui
+        Qt::GuiPrivate
 )
-
-#### Keys ignored in scope 1:.:.:gif.pro:<TRUE>:
-# OTHER_FILES = "gif.json"
diff --git a/src/plugins/imageformats/gif/main.cpp b/src/plugins/imageformats/gif/main.cpp
index 993871420c..f98b586407 100644
--- a/src/plugins/imageformats/gif/main.cpp
+++ b/src/plugins/imageformats/gif/main.cpp
@@ -1,47 +1,9 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the plugins 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.
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
 #include <qimageiohandler.h>
 #include <qstringlist.h>
 
-#include "main.h"
-
 #ifdef QT_NO_IMAGEFORMAT_GIF
 #undef QT_NO_IMAGEFORMAT_GIF
 #endif
@@ -49,6 +11,17 @@
 
 QT_BEGIN_NAMESPACE
 
+class QGifPlugin : public QImageIOPlugin
+{
+    Q_OBJECT
+    Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QImageIOHandlerFactoryInterface" FILE "gif.json")
+public:
+    QGifPlugin();
+    ~QGifPlugin();
+
+    Capabilities capabilities(QIODevice *device, const QByteArray &format) const override;
+    QImageIOHandler *create(QIODevice *device, const QByteArray &format = QByteArray()) const override;
+};
 
 QGifPlugin::QGifPlugin()
 {
@@ -74,3 +47,5 @@ QImageIOHandler *QGifPlugin::create(QIODevice *device, const QByteArray &format)
 }
 
 QT_END_NAMESPACE
+
+#include "main.moc"
diff --git a/src/plugins/imageformats/gif/main.h b/src/plugins/imageformats/gif/main.h
deleted file mode 100644
index 84913a31d7..0000000000
--- a/src/plugins/imageformats/gif/main.h
+++ /dev/null
@@ -1,62 +0,0 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the plugins 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 <qimageiohandler.h>
-#include <qstringlist.h>
-
-#ifdef QT_NO_IMAGEFORMAT_GIF
-#undef QT_NO_IMAGEFORMAT_GIF
-#endif
-#include <qgifhandler_p.h>
-
-QT_BEGIN_NAMESPACE
-
-class QGifPlugin : public QImageIOPlugin
-{
-    Q_OBJECT
-    Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QImageIOHandlerFactoryInterface" FILE "gif.json")
-public:
-    QGifPlugin();
-    ~QGifPlugin();
-
-    Capabilities capabilities(QIODevice *device, const QByteArray &format) const override;
-    QImageIOHandler *create(QIODevice *device, const QByteArray &format = QByteArray()) const override;
-};
-
-QT_END_NAMESPACE
diff --git a/src/plugins/imageformats/gif/qgifhandler.cpp b/src/plugins/imageformats/gif/qgifhandler.cpp
index 2103f5f6fe..8ad4ff7510 100644
--- a/src/plugins/imageformats/gif/qgifhandler.cpp
+++ b/src/plugins/imageformats/gif/qgifhandler.cpp
@@ -1,46 +1,5 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the plugins 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.
-**
-** $QT_END_LICENSE$
-**
-** WARNING:
-**      A separate license from Unisys may be required to use the gif
-**      reader. See http://www.unisys.com/about__unisys/lzw/
-**      for information from Unisys
-**
-****************************************************************************/
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
 #include "qgifhandler_p.h"
 
@@ -1187,9 +1146,9 @@ QVariant QGifHandler::option(ImageOption option) const
         }
         // before the first frame is read, or we have an empty data stream
         if (frameNumber == -1)
-            return (imageSizes.count() > 0) ? QVariant(imageSizes.at(0)) : QVariant();
+            return (imageSizes.size() > 0) ? QVariant(imageSizes.at(0)) : QVariant();
         // after the last frame has been read, the next size is undefined
-        if (frameNumber >= imageSizes.count() - 1)
+        if (frameNumber >= imageSizes.size() - 1)
             return QVariant();
         // and the last case: the size of the next frame
         return imageSizes.at(frameNumber + 1);
@@ -1216,7 +1175,7 @@ int QGifHandler::imageCount() const
         QGIFFormat::scan(device(), &imageSizes, &loopCnt);
         scanIsCached = true;
     }
-    return imageSizes.count();
+    return imageSizes.size();
 }
 
 int QGifHandler::loopCount() const
diff --git a/src/plugins/imageformats/gif/qgifhandler_p.h b/src/plugins/imageformats/gif/qgifhandler_p.h
index 9508e9ac92..a27acf174d 100644
--- a/src/plugins/imageformats/gif/qgifhandler_p.h
+++ b/src/plugins/imageformats/gif/qgifhandler_p.h
@@ -1,46 +1,5 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the plugins 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.
-**
-** $QT_END_LICENSE$
-**
-** WARNING:
-**      A separate license from Unisys may be required to use the gif
-**      reader. See http://www.unisys.com/about__unisys/lzw/
-**      for information from Unisys
-**
-****************************************************************************/
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
 #ifndef QGIFHANDLER_P_H
 #define QGIFHANDLER_P_H
diff --git a/src/plugins/imageformats/ico/CMakeLists.txt b/src/plugins/imageformats/ico/CMakeLists.txt
index 2d1dc38e17..c9cd0f0d40 100644
--- a/src/plugins/imageformats/ico/CMakeLists.txt
+++ b/src/plugins/imageformats/ico/CMakeLists.txt
@@ -1,4 +1,5 @@
-# Generated from ico.pro.
+# Copyright (C) 2022 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
 
 #####################################################################
 ## QICOPlugin Plugin:
@@ -6,15 +7,13 @@
 
 qt_internal_add_plugin(QICOPlugin
     OUTPUT_NAME qico
-    TYPE imageformats
+    PLUGIN_TYPE imageformats
     SOURCES
-        main.cpp main.h
+        main.cpp
         qicohandler.cpp qicohandler.h
     LIBRARIES
         Qt::Core
         Qt::CorePrivate
         Qt::Gui
+    NO_UNITY_BUILD
 )
-
-#### Keys ignored in scope 1:.:.:ico.pro:<TRUE>:
-# OTHER_FILES = "ico.json"
diff --git a/src/plugins/imageformats/ico/main.cpp b/src/plugins/imageformats/ico/main.cpp
index b00d8c7fd3..d5199fa18b 100644
--- a/src/plugins/imageformats/ico/main.cpp
+++ b/src/plugins/imageformats/ico/main.cpp
@@ -1,46 +1,25 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the plugins 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.
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
-#include "main.h"
+#include <qimageiohandler.h>
+#include <qdebug.h>
+
+#ifdef QT_NO_IMAGEFORMAT_ICO
+#undef QT_NO_IMAGEFORMAT_ICO
+#endif
+#include "qicohandler.h"
 
 QT_BEGIN_NAMESPACE
 
+class QICOPlugin : public QImageIOPlugin
+{
+    Q_OBJECT
+    Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QImageIOHandlerFactoryInterface" FILE "ico.json")
+public:
+    Capabilities capabilities(QIODevice *device, const QByteArray &format) const override;
+    QImageIOHandler *create(QIODevice *device, const QByteArray &format = QByteArray()) const override;
+};
+
 QImageIOPlugin::Capabilities QICOPlugin::capabilities(QIODevice *device, const QByteArray &format) const
 {
     if (format == "ico" || format == "cur")
@@ -67,3 +46,5 @@ QImageIOHandler *QICOPlugin::create(QIODevice *device, const QByteArray &format)
 }
 
 QT_END_NAMESPACE
+
+#include "main.moc"
diff --git a/src/plugins/imageformats/ico/main.h b/src/plugins/imageformats/ico/main.h
deleted file mode 100644
index b5875183c1..0000000000
--- a/src/plugins/imageformats/ico/main.h
+++ /dev/null
@@ -1,59 +0,0 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the plugins 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 <qimageiohandler.h>
-#include <qdebug.h>
-
-#ifdef QT_NO_IMAGEFORMAT_ICO
-#undef QT_NO_IMAGEFORMAT_ICO
-#endif
-#include "qicohandler.h"
-
-QT_BEGIN_NAMESPACE
-
-class QICOPlugin : public QImageIOPlugin
-{
-    Q_OBJECT
-    Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QImageIOHandlerFactoryInterface" FILE "ico.json")
-public:
-    Capabilities capabilities(QIODevice *device, const QByteArray &format) const override;
-    QImageIOHandler *create(QIODevice *device, const QByteArray &format = QByteArray()) const override;
-};
-
-QT_END_NAMESPACE
diff --git a/src/plugins/imageformats/ico/qicohandler.cpp b/src/plugins/imageformats/ico/qicohandler.cpp
index 1b084e2eea..18b39766f5 100644
--- a/src/plugins/imageformats/ico/qicohandler.cpp
+++ b/src/plugins/imageformats/ico/qicohandler.cpp
@@ -1,41 +1,5 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the plugins 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.
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
 /*!
     \class QtIcoHandler
@@ -59,6 +23,8 @@ QT_BEGIN_NAMESPACE
 
 Q_LOGGING_CATEGORY(lcIco, "qt.gui.imageio.ico")
 
+namespace {
+
 // These next two structs represent how the icon information is stored
 // in an ICO file.
 typedef struct
@@ -98,6 +64,8 @@ typedef struct {                    // BMP information header
 } BMP_INFOHDR ,*LPBMP_INFOHDR;
 #define BMP_INFOHDR_SIZE 40
 
+}
+
 class ICOReader
 {
 public:
@@ -208,9 +176,7 @@ bool ICOReader::canRead(QIODevice *iodev)
 
         ICONDIR ikonDir;
         if (readIconDir(iodev, &ikonDir)) {
-            qint64 readBytes = ICONDIR_SIZE;
             if (readIconDirEntry(iodev, &ikonDir.idEntries[0])) {
-                readBytes += ICONDIRENTRY_SIZE;
                 // ICO format does not have a magic identifier, so we read 6 different values, which will hopefully be enough to identify the file.
                 if (   ikonDir.idReserved == 0
                     && (ikonDir.idType == 1 || ikonDir.idType == 2)
@@ -468,7 +434,9 @@ QImage ICOReader::iconAt(int index)
 
             static const uchar pngMagicData[] = { 137, 80, 78, 71, 13, 10, 26, 10 };
 
-            iod->seek(iconEntry.dwImageOffset);
+            if (!iod->seek(iconEntry.dwImageOffset)
+                || iconEntry.dwBytesInRes > iod->bytesAvailable())
+                return img;
 
             const QByteArray pngMagic = QByteArray::fromRawData((const char*)pngMagicData, sizeof(pngMagicData));
             const bool isPngImage = (iod->read(pngMagic.size()) == pngMagic);
@@ -531,7 +499,7 @@ QImage ICOReader::iconAt(int index)
                     if (!image.isNull()) {
                         readBMP(image);
                         if (!image.isNull()) {
-                            if (icoAttrib.depth == 32) {
+                            if (icoAttrib.nbits == 32) {
                                 img = std::move(image).convertToFormat(QImage::Format_ARGB32_Premultiplied);
                             } else {
                                 QImage mask(image.width(), image.height(), QImage::Format_Mono);
@@ -597,14 +565,14 @@ bool ICOReader::write(QIODevice *device, const QList<QImage> &images)
 {
     bool retValue = false;
 
-    if (images.count()) {
+    if (images.size()) {
 
         qint64 origOffset = device->pos();
 
         ICONDIR id;
         id.idReserved = 0;
         id.idType = 1;
-        id.idCount = images.count();
+        id.idCount = images.size();
 
         ICONDIRENTRY * entries = new ICONDIRENTRY[id.idCount];
         BMP_INFOHDR * bmpHeaders = new BMP_INFOHDR[id.idCount];
@@ -767,6 +735,8 @@ bool QtIcoHandler::supportsOption(ImageOption option) const
  */
 bool QtIcoHandler::canRead() const
 {
+    if (knownCanRead)
+        return true;
     bool bCanRead = false;
     QIODevice *device = QImageIOHandler::device();
     if (device) {
@@ -776,6 +746,7 @@ bool QtIcoHandler::canRead() const
     } else {
         qCWarning(lcIco, "QtIcoHandler::canRead() called with no device");
     }
+    knownCanRead = bCanRead;
     return bCanRead;
 }
 
diff --git a/src/plugins/imageformats/ico/qicohandler.h b/src/plugins/imageformats/ico/qicohandler.h
index 0d44a67dfc..61c3eea465 100644
--- a/src/plugins/imageformats/ico/qicohandler.h
+++ b/src/plugins/imageformats/ico/qicohandler.h
@@ -1,41 +1,5 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the plugins 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.
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 #ifndef QTICOHANDLER_H
 #define QTICOHANDLER_H
 
@@ -66,7 +30,7 @@ public:
 private:
     int m_currentIconIndex;
     ICOReader *m_pICOReader;
-
+    mutable bool knownCanRead = false;
 };
 
 QT_END_NAMESPACE
diff --git a/src/plugins/imageformats/jpeg/CMakeLists.txt b/src/plugins/imageformats/jpeg/CMakeLists.txt
index f0f910d9fd..6b077a7647 100644
--- a/src/plugins/imageformats/jpeg/CMakeLists.txt
+++ b/src/plugins/imageformats/jpeg/CMakeLists.txt
@@ -1,6 +1,7 @@
-# Generated from jpeg.pro.
+# Copyright (C) 2022 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
 
-qt_find_package(JPEG) # special case
+qt_find_package(WrapJpeg PROVIDED_TARGETS WrapJpeg::WrapJpeg)
 
 #####################################################################
 ## QJpegPlugin Plugin:
@@ -8,15 +9,16 @@ qt_find_package(JPEG) # special case
 
 qt_internal_add_plugin(QJpegPlugin
     OUTPUT_NAME qjpeg
-    TYPE imageformats
+    PLUGIN_TYPE imageformats
     SOURCES
-        main.cpp main.h
+        main.cpp
         qjpeghandler.cpp qjpeghandler_p.h
     LIBRARIES
         Qt::Core
         Qt::CorePrivate
         Qt::Gui
         Qt::GuiPrivate
+        WrapJpeg::WrapJpeg
 )
 
 # Fails to build on Windows with a static Qt, PCH enabled and
@@ -25,86 +27,3 @@ qt_internal_add_plugin(QJpegPlugin
 if(WIN32 AND NOT BUILD_SHARED_LIBS)
     qt_update_ignore_pch_source(QJpegPlugin "qjpeghandler.cpp")
 endif()
-
-#### Keys ignored in scope 1:.:.:jpeg.pro:<TRUE>:
-# OTHER_FILES = "jpeg.json"
-
-## Scopes:
-#####################################################################
-
-qt_internal_extend_target(QJpegPlugin CONDITION QT_FEATURE_system_jpeg
-    PUBLIC_LIBRARIES
-        JPEG::JPEG
-)
-
-qt_internal_extend_target(QJpegPlugin CONDITION NOT QT_FEATURE_system_jpeg
-    SOURCES
-        ../../../3rdparty/libjpeg/src/jaricom.c
-        ../../../3rdparty/libjpeg/src/jcapimin.c
-        ../../../3rdparty/libjpeg/src/jcapistd.c
-        ../../../3rdparty/libjpeg/src/jcarith.c
-        ../../../3rdparty/libjpeg/src/jccoefct.c
-        ../../../3rdparty/libjpeg/src/jccolor.c
-        ../../../3rdparty/libjpeg/src/jcdctmgr.c
-        ../../../3rdparty/libjpeg/src/jchuff.c
-        ../../../3rdparty/libjpeg/src/jcinit.c
-        ../../../3rdparty/libjpeg/src/jcmainct.c
-        ../../../3rdparty/libjpeg/src/jcmarker.c
-        ../../../3rdparty/libjpeg/src/jcmaster.c
-        ../../../3rdparty/libjpeg/src/jcomapi.c
-        ../../../3rdparty/libjpeg/src/jcparam.c
-        ../../../3rdparty/libjpeg/src/jcphuff.c
-        ../../../3rdparty/libjpeg/src/jcprepct.c
-        ../../../3rdparty/libjpeg/src/jcsample.c
-        ../../../3rdparty/libjpeg/src/jctrans.c
-        ../../../3rdparty/libjpeg/src/jdapimin.c
-        ../../../3rdparty/libjpeg/src/jdapistd.c
-        ../../../3rdparty/libjpeg/src/jdarith.c
-        ../../../3rdparty/libjpeg/src/jdatadst.c
-        ../../../3rdparty/libjpeg/src/jdatasrc.c
-        ../../../3rdparty/libjpeg/src/jdcoefct.c
-        ../../../3rdparty/libjpeg/src/jdcolor.c
-        ../../../3rdparty/libjpeg/src/jddctmgr.c
-        ../../../3rdparty/libjpeg/src/jdhuff.c
-        ../../../3rdparty/libjpeg/src/jdinput.c
-        ../../../3rdparty/libjpeg/src/jdmainct.c
-        ../../../3rdparty/libjpeg/src/jdmarker.c
-        ../../../3rdparty/libjpeg/src/jdmaster.c
-        ../../../3rdparty/libjpeg/src/jdmerge.c
-        ../../../3rdparty/libjpeg/src/jdphuff.c
-        ../../../3rdparty/libjpeg/src/jdpostct.c
-        ../../../3rdparty/libjpeg/src/jdsample.c
-        ../../../3rdparty/libjpeg/src/jdtrans.c
-        ../../../3rdparty/libjpeg/src/jerror.c
-        ../../../3rdparty/libjpeg/src/jfdctflt.c
-        ../../../3rdparty/libjpeg/src/jfdctfst.c
-        ../../../3rdparty/libjpeg/src/jfdctint.c
-        ../../../3rdparty/libjpeg/src/jidctflt.c
-        ../../../3rdparty/libjpeg/src/jidctfst.c
-        ../../../3rdparty/libjpeg/src/jidctint.c
-        ../../../3rdparty/libjpeg/src/jidctred.c
-        ../../../3rdparty/libjpeg/src/jmemmgr.c
-        ../../../3rdparty/libjpeg/src/jmemnobs.c
-        ../../../3rdparty/libjpeg/src/jquant1.c
-        ../../../3rdparty/libjpeg/src/jquant2.c
-        ../../../3rdparty/libjpeg/src/jsimd_none.c
-        ../../../3rdparty/libjpeg/src/jutils.c
-    INCLUDE_DIRECTORIES
-        ../../../3rdparty/libjpeg/src
-)
-
-# special case begin
-if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU"
-    OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang"
-    OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang")
-    target_compile_options(QJpegPlugin PRIVATE "-Wno-unused-parameter")
-endif()
-# special case end
-
-#### Keys ignored in scope 5:.:../../../3rdparty:../../../3rdparty/libjpeg.pri:GCC:
-# QMAKE_CFLAGS_WARN_ON = "-Wno-unused-parameter" "-Wno-main"
-
-qt_internal_extend_target(QJpegPlugin CONDITION MSVC AND NOT QT_FEATURE_system_jpeg
-    DEFINES
-        _CRT_SECURE_NO_WARNINGS
-)
diff --git a/src/plugins/imageformats/jpeg/main.cpp b/src/plugins/imageformats/jpeg/main.cpp
index 83f13c4a9d..c869d07650 100644
--- a/src/plugins/imageformats/jpeg/main.cpp
+++ b/src/plugins/imageformats/jpeg/main.cpp
@@ -1,43 +1,8 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the plugins 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.
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
-#include "main.h"
+#include <qimageiohandler.h>
+#include <qstringlist.h>
 
 #ifdef QT_NO_IMAGEFORMAT_JPEG
 #undef QT_NO_IMAGEFORMAT_JPEG
@@ -46,6 +11,15 @@
 
 QT_BEGIN_NAMESPACE
 
+class QJpegPlugin : public QImageIOPlugin
+{
+    Q_OBJECT
+    Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QImageIOHandlerFactoryInterface" FILE "jpeg.json")
+public:
+    Capabilities capabilities(QIODevice *device, const QByteArray &format) const override;
+    QImageIOHandler *create(QIODevice *device, const QByteArray &format = QByteArray()) const override;
+};
+
 QImageIOPlugin::Capabilities QJpegPlugin::capabilities(QIODevice *device, const QByteArray &format) const
 {
     if (format == "jpeg" || format == "jpg")
@@ -72,3 +46,5 @@ QImageIOHandler *QJpegPlugin::create(QIODevice *device, const QByteArray &format
 }
 
 QT_END_NAMESPACE
+
+#include "main.moc"
diff --git a/src/plugins/imageformats/jpeg/main.h b/src/plugins/imageformats/jpeg/main.h
deleted file mode 100644
index 1845c8c124..0000000000
--- a/src/plugins/imageformats/jpeg/main.h
+++ /dev/null
@@ -1,58 +0,0 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the plugins 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 <qimageiohandler.h>
-#include <qstringlist.h>
-
-#ifdef QT_NO_IMAGEFORMAT_JPEG
-#undef QT_NO_IMAGEFORMAT_JPEG
-#endif
-
-QT_BEGIN_NAMESPACE
-
-class QJpegPlugin : public QImageIOPlugin
-{
-    Q_OBJECT
-    Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QImageIOHandlerFactoryInterface" FILE "jpeg.json")
-public:
-    Capabilities capabilities(QIODevice *device, const QByteArray &format) const override;
-    QImageIOHandler *create(QIODevice *device, const QByteArray &format = QByteArray()) const override;
-};
-
-QT_END_NAMESPACE
diff --git a/src/plugins/imageformats/jpeg/qjpeghandler.cpp b/src/plugins/imageformats/jpeg/qjpeghandler.cpp
index a17afc0f69..59b73587c5 100644
--- a/src/plugins/imageformats/jpeg/qjpeghandler.cpp
+++ b/src/plugins/imageformats/jpeg/qjpeghandler.cpp
@@ -1,41 +1,5 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the plugins 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.
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
 #include "qjpeghandler_p.h"
 
@@ -85,10 +49,8 @@ extern "C" {
 
 static void my_error_exit (j_common_ptr cinfo)
 {
+    (*cinfo->err->output_message)(cinfo);
     my_error_mgr* myerr = (my_error_mgr*) cinfo->err;
-    char buffer[JMSG_LENGTH_MAX];
-    (*cinfo->err->format_message)(cinfo, buffer);
-    qCWarning(lcJpeg, "%s", buffer);
     longjmp(myerr->setjmp_buffer, 1);
 }
 
@@ -210,9 +172,14 @@ inline static bool read_jpeg_format(QImage::Format &format, j_decompress_ptr cin
         format = QImage::Format_Grayscale8;
         break;
     case 3:
-    case 4:
         format = QImage::Format_RGB32;
         break;
+    case 4:
+        if (cinfo->out_color_space == JCS_CMYK)
+            format = QImage::Format_CMYK8888;
+        else
+            format = QImage::Format_RGB32;
+        break;
     default:
         result = false;
         break;
@@ -230,9 +197,14 @@ static bool ensureValidImage(QImage *dest, struct jpeg_decompress_struct *info,
         format = QImage::Format_Grayscale8;
         break;
     case 3:
-    case 4:
         format = QImage::Format_RGB32;
         break;
+    case 4:
+        if (info->out_color_space == JCS_CMYK)
+            format = QImage::Format_CMYK8888;
+        else
+            format = QImage::Format_RGB32;
+        break;
     default:
         return false; // unsupported format
     }
@@ -244,7 +216,7 @@ static bool read_jpeg_image(QImage *outImage,
                             QSize scaledSize, QRect scaledClipRect,
                             QRect clipRect, int quality,
                             Rgb888ToRgb32Converter converter,
-                            j_decompress_ptr info, struct my_error_mgr* err  )
+                            j_decompress_ptr info, struct my_error_mgr* err, bool invertCMYK)
 {
     if (!setjmp(err->setjmp_buffer)) {
         // -1 means default quality.
@@ -353,7 +325,7 @@ static bool read_jpeg_image(QImage *outImage,
 
         // Allocate memory for the clipped QImage.
         if (!ensureValidImage(outImage, info, clip.size()))
-            longjmp(err->setjmp_buffer, 1);
+            return false;
 
         // Avoid memcpy() overhead if grayscale with no clipping.
         bool quickGray = (info->output_components == 1 &&
@@ -386,14 +358,15 @@ static bool read_jpeg_image(QImage *outImage,
                     QRgb *out = (QRgb*)outImage->scanLine(y);
                     converter(out, in, clip.width());
                 } else if (info->out_color_space == JCS_CMYK) {
-                    // Convert CMYK->RGB.
                     uchar *in = rows[0] + clip.x() * 4;
-                    QRgb *out = (QRgb*)outImage->scanLine(y);
-                    for (int i = 0; i < clip.width(); ++i) {
-                        int k = in[3];
-                        *out++ = qRgb(k * in[0] / 255, k * in[1] / 255,
-                                      k * in[2] / 255);
-                        in += 4;
+                    quint32 *out = (quint32*)outImage->scanLine(y);
+                    if (invertCMYK) {
+                        for (int i = 0; i < clip.width(); ++i) {
+                            *out++ = 0xffffffffu - (in[0] | in[1] << 8 | in[2] << 16 | in[3] << 24);
+                            in += 4;
+                        }
+                    } else {
+                        memcpy(out, in, clip.width() * 4);
                     }
                 } else if (info->output_components == 1) {
                     // Grayscale.
@@ -429,8 +402,10 @@ static bool read_jpeg_image(QImage *outImage,
             *outImage = outImage->copy(scaledClipRect);
         return !outImage->isNull();
     }
-    else
+    else {
+        my_output_message(j_common_ptr(info));
         return false;
+    }
 }
 
 struct my_jpeg_destination_mgr : public jpeg_destination_mgr {
@@ -495,7 +470,7 @@ static inline void set_text(const QImage &image, j_compress_ptr cinfo, const QSt
         if (!comment.isEmpty())
             comment += ": ";
         comment += it.value().toUtf8();
-        if (comment.length() > maxMarkerSize)
+        if (comment.size() > maxMarkerSize)
             comment.truncate(maxMarkerSize);
         jpeg_write_marker(cinfo, JPEG_COM, (const JOCTET *)comment.constData(), comment.size());
     }
@@ -529,7 +504,8 @@ static bool do_write_jpeg_image(struct jpeg_compress_struct &cinfo,
                                 int sourceQuality,
                                 const QString &description,
                                 bool optimize,
-                                bool progressive)
+                                bool progressive,
+                                bool invertCMYK)
 {
     bool success = false;
     const QList<QRgb> cmap = image.colorTable();
@@ -569,10 +545,15 @@ static bool do_write_jpeg_image(struct jpeg_compress_struct &cinfo,
             cinfo.in_color_space = gray ? JCS_GRAYSCALE : JCS_RGB;
             break;
         case QImage::Format_Grayscale8:
+        case QImage::Format_Grayscale16:
             gray = true;
             cinfo.input_components = 1;
             cinfo.in_color_space = JCS_GRAYSCALE;
             break;
+        case QImage::Format_CMYK8888:
+            cinfo.input_components = 4;
+            cinfo.in_color_space = JCS_CMYK;
+            break;
         default:
             cinfo.input_components = 3;
             cinfo.in_color_space = JCS_RGB;
@@ -605,7 +586,7 @@ static bool do_write_jpeg_image(struct jpeg_compress_struct &cinfo,
         jpeg_start_compress(&cinfo, TRUE);
 
         set_text(image, &cinfo, description);
-        if (cinfo.in_color_space == JCS_RGB)
+        if (cinfo.in_color_space == JCS_RGB || cinfo.in_color_space == JCS_CMYK)
             write_icc_profile(image, &cinfo);
 
         row_pointer[0] = new uchar[cinfo.image_width*cinfo.input_components];
@@ -667,6 +648,12 @@ static bool do_write_jpeg_image(struct jpeg_compress_struct &cinfo,
             case QImage::Format_Grayscale8:
                 memcpy(row, image.constScanLine(cinfo.next_scanline), w);
                 break;
+            case QImage::Format_Grayscale16:
+                {
+                    QImage rowImg = image.copy(0, cinfo.next_scanline, w, 1).convertToFormat(QImage::Format_Grayscale8);
+                    memcpy(row, rowImg.constScanLine(0), w);
+                }
+                break;
             case QImage::Format_RGB888:
                 memcpy(row, image.constScanLine(cinfo.next_scanline), w * 3);
                 break;
@@ -683,6 +670,17 @@ static bool do_write_jpeg_image(struct jpeg_compress_struct &cinfo,
                     }
                 }
                 break;
+            case QImage::Format_CMYK8888: {
+                auto *cmykIn = reinterpret_cast<const quint32 *>(image.constScanLine(cinfo.next_scanline));
+                auto *cmykOut = reinterpret_cast<quint32 *>(row);
+                if (invertCMYK) {
+                    for (int i = 0; i < w; ++i)
+                        cmykOut[i] = 0xffffffffu - cmykIn[i];
+                } else {
+                    memcpy(cmykOut, cmykIn, w * 4);
+                }
+                break;
+            }
             default:
                 {
                     // (Testing shows that this way is actually faster than converting to RGB888 + memcpy)
@@ -704,6 +702,7 @@ static bool do_write_jpeg_image(struct jpeg_compress_struct &cinfo,
         jpeg_destroy_compress(&cinfo);
         success = true;
     } else {
+        my_output_message(j_common_ptr(&cinfo));
         jpeg_destroy_compress(&cinfo);
         success = false;
     }
@@ -717,7 +716,8 @@ static bool write_jpeg_image(const QImage &image,
                              int sourceQuality,
                              const QString &description,
                              bool optimize,
-                             bool progressive)
+                             bool progressive,
+                             bool invertCMYK)
 {
     // protect these objects from the setjmp/longjmp pair inside
     // do_write_jpeg_image (by making them non-local).
@@ -728,7 +728,7 @@ static bool write_jpeg_image(const QImage &image,
     const bool success = do_write_jpeg_image(cinfo, row_pointer,
                                              image, device,
                                              sourceQuality, description,
-                                             optimize, progressive);
+                                             optimize, progressive, invertCMYK);
 
     delete [] row_pointer[0];
     return success;
@@ -773,6 +773,21 @@ public:
     QStringList readTexts;
     QByteArray iccProfile;
 
+    // Photoshop historically invertes the quantities in CMYK JPEG files:
+    // 0 means 100% ink, 255 means no ink. Every reader does the same,
+    // for compatibility reasons.
+    // Use such an interpretation by default, but also offer the alternative
+    // of not inverting the channels.
+    // This is just a "fancy" API; it could be reduced to a boolean setting
+    // for CMYK files.
+    enum class SubType {
+        Automatic,
+        Inverted_CMYK,
+        CMYK,
+        NSubTypes
+    };
+    SubType subType = SubType::Automatic;
+
     struct jpeg_decompress_struct info;
     struct my_jpeg_source_mgr * iod_src;
     struct my_error_mgr err;
@@ -787,6 +802,14 @@ public:
     QJpegHandler *q;
 };
 
+static const char SupportedJPEGSubtypes[][14] = {
+    "Automatic",
+    "Inverted_CMYK",
+    "CMYK"
+};
+
+static_assert(std::size(SupportedJPEGSubtypes) == size_t(QJpegHandlerPrivate::SubType::NSubTypes));
+
 static bool readExifHeader(QDataStream &stream)
 {
     char prefix[6];
@@ -986,8 +1009,8 @@ bool QJpegHandlerPrivate::readJpegHeader(QIODevice *device)
             state = ReadHeader;
             return true;
         }
-        else
-        {
+        else {
+            my_output_message(j_common_ptr(&info));
             return false;
         }
     }
@@ -1003,7 +1026,8 @@ bool QJpegHandlerPrivate::read(QImage *image)
 
     if (state == ReadHeader)
     {
-        bool success = read_jpeg_image(image, scaledSize, scaledClipRect, clipRect, quality, rgb888ToRgb32ConverterPtr, &info, &err);
+        const bool invertCMYK = subType != QJpegHandlerPrivate::SubType::CMYK;
+        bool success = read_jpeg_image(image, scaledSize, scaledClipRect, clipRect, quality, rgb888ToRgb32ConverterPtr, &info, &err, invertCMYK);
         if (success) {
             for (int i = 0; i < readTexts.size()-1; i+=2)
                 image->setText(readTexts.at(i), readTexts.at(i+1));
@@ -1089,13 +1113,14 @@ extern void qt_imageTransform(QImage &src, QImageIOHandler::Transformations orie
 
 bool QJpegHandler::write(const QImage &image)
 {
+    const bool invertCMYK = d->subType != QJpegHandlerPrivate::SubType::CMYK;
     if (d->transformation != QImageIOHandler::TransformationNone) {
         // We don't support writing EXIF headers so apply the transform to the data.
         QImage img = image;
         qt_imageTransform(img, d->transformation);
-        return write_jpeg_image(img, device(), d->quality, d->description, d->optimize, d->progressive);
+        return write_jpeg_image(img, device(), d->quality, d->description, d->optimize, d->progressive, invertCMYK);
     }
-    return write_jpeg_image(image, device(), d->quality, d->description, d->optimize, d->progressive);
+    return write_jpeg_image(image, device(), d->quality, d->description, d->optimize, d->progressive, invertCMYK);
 }
 
 bool QJpegHandler::supportsOption(ImageOption option) const
@@ -1106,6 +1131,8 @@ bool QJpegHandler::supportsOption(ImageOption option) const
         || option == ClipRect
         || option == Description
         || option == Size
+        || option == SubType
+        || option == SupportedSubTypes
         || option == ImageFormat
         || option == OptimizedWrite
         || option == ProgressiveScanWrite
@@ -1129,6 +1156,13 @@ QVariant QJpegHandler::option(ImageOption option) const
     case Size:
         d->readJpegHeader(device());
         return d->size;
+    case SubType:
+        return QByteArray(SupportedJPEGSubtypes[int(d->subType)]);
+    case SupportedSubTypes: {
+        QByteArrayList list(std::begin(SupportedJPEGSubtypes),
+                            std::end(SupportedJPEGSubtypes));
+        return QVariant::fromValue(list);
+    }
     case ImageFormat:
         d->readJpegHeader(device());
         return d->format;
@@ -1164,6 +1198,16 @@ void QJpegHandler::setOption(ImageOption option, const QVariant &value)
     case Description:
         d->description = value.toString();
         break;
+    case SubType: {
+        const QByteArray subType = value.toByteArray();
+        for (size_t i = 0; i < std::size(SupportedJPEGSubtypes); ++i) {
+            if (subType == SupportedJPEGSubtypes[i]) {
+                d->subType = QJpegHandlerPrivate::SubType(i);
+                break;
+            }
+        }
+        break;
+    }
     case OptimizedWrite:
         d->optimize = value.toBool();
         break;
@@ -1174,6 +1218,7 @@ void QJpegHandler::setOption(ImageOption option, const QVariant &value)
         int transformation = value.toInt();
         if (transformation > 0 && transformation < 8)
             d->transformation = QImageIOHandler::Transformations(transformation);
+        break;
     }
     default:
         break;
diff --git a/src/plugins/imageformats/jpeg/qjpeghandler_p.h b/src/plugins/imageformats/jpeg/qjpeghandler_p.h
index 43ca17317a..e246f7a6e1 100644
--- a/src/plugins/imageformats/jpeg/qjpeghandler_p.h
+++ b/src/plugins/imageformats/jpeg/qjpeghandler_p.h
@@ -1,41 +1,5 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the plugins 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.
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
 #ifndef QJPEGHANDLER_P_H
 #define QJPEGHANDLER_P_H