QScreenCapture Class

Detailed Description

The class captures a screen. It is managed by the QMediaCaptureSession class where the captured view can be displayed in a window or recorded to a file.

QMediaCaptureSession session;
QAudioInput audioInput;
session.setAudioInput(&input);
QMediaRecorder recorder;
session.setRecorder(&recorder);
recorder.setQuality(QMediaRecorder::HighQuality);
recorder.setOutputLocation(QUrl::fromLocalFile("test.mp3"));
recorder.record();

Screen Capture Limitations

On Qt 6.5.2 and above, the following limitations apply to using QScreenCapture:

• It is only supported with the FFmpeg backend.
• It is unsupported on Linux with Wayland compositor, due to Wayland protocol restrictions and limitations.
• It is not supported on mobile operating systems, except on Android. There, you might run into performance issues as the class is currently implemented via QScreen::grabWindow, which is not optimal for the use case.
• On embedded with EGLFS, it has limited functionality. Capturing Widget-based applications works from Qt 6.5.5, and capturring Quick-based applications works from Qt 6.5.6. For Qt Quick applications, the class is currently implemented via QQuickWindow::grabWindow, which can cause performance issues.
• 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.