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// Copyright (C) 2024 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
/*!
//! [content]
\section1 Screen Capture Limitations
On Qt 6.5.2 and above, the following limitations apply to using \1ScreenCapture:
\list
\li It is only supported with the FFmpeg backend.
\li On some platforms, no new video frames are emitted while the
captured screen content remains unchanged. Applications should
therefore not rely on receiving a continuous stream of frames at
the requested frame rate.
\li On Linux systems using the Wayland compositor, the screen capture implementation
is experimental and comes with the following limitations.
Due to restrictions of the Wayland protocol, it's impossible to set and get
the target screen via the API of the \c QScreenCapture class. Instead, the OS will
show a screen selection wizard upon invoking \c QScreenCapture::setActive(true).
The screen capture feature requires the installation of
the \l {https://flatpak.github.io/xdg-desktop-portal/docs/doc-org.freedesktop.portal.ScreenCast.html}{ScreenCast}
These limitations might change in the future.
\li It is not supported on mobile operating systems, except on Android.
Screen Capture on Android needs additional \l{Android foreground service
permission} to be added to the \c AndroidManifest.xml file:
\badcode
<manifest ...>
<uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
<uses-permission android:name="android.permission.FOREGROUND_SERVICE_MEDIA_PROJECTION" />
<application ...>
<service android:name="org.qtproject.qt.android.multimedia.QtScreenCaptureService"
android:foregroundServiceType="mediaProjection"
android:exported="false"/>
</service>
</application>
</manifest>
\endcode
\li On embedded with EGLFS, it has limited functionality. For Qt Quick
applications, the class is currently implemented via
QQuickWindow::grabWindow, which can cause performance issues.
\li In most cases, we set a screen capture frame rate that equals the screen
refresh rate, except on Windows, where the rate might be flexible.
Such a frame rate (75/120 FPS) might cause performance issues on weak
CPUs if the captured screen is of 4K resolution. On EGLFS, the capture
frame rate is currently locked to 30 FPS.
\endlist
//! [content]
*/