qcam: main_window: Move capture event processing to main thread

To avoid blocking the camera manager for a long amount of time, move
capture event processing to the main thread. Captured buffers are added
to a queue and an event is posted to the main window to signal
availability of a buffer.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/src/qcam/main_window.h b/src/qcam/main_window.h
index 720a3393..c623120d 100644
--- a/src/qcam/main_window.h
+++ b/src/qcam/main_window.h
@@ -11,7 +11,9 @@
 
 #include <QElapsedTimer>
 #include <QMainWindow>
+#include <QMutex>
 #include <QObject>
+#include <QQueue>
 #include <QTimer>
 
 #include <libcamera/buffer.h>
@@ -40,6 +42,8 @@ public:
 	MainWindow(CameraManager *cm, const OptionsParser::Options &options);
 	~MainWindow();
 
+	bool event(QEvent *e) override;
+
 private Q_SLOTS:
 	void quit();
 	void updateTitle();
@@ -57,6 +61,7 @@ private:
 	int openCamera();
 
 	void requestComplete(Request *request);
+	void processCapture();
 	int display(FrameBuffer *buffer);
 	void queueRequest(FrameBuffer *buffer);
 
@@ -78,6 +83,9 @@ private:
 	uint32_t previousFrames_;
 	uint32_t framesCaptured_;
 
+	QMutex mutex_;
+	QQueue<FrameBuffer *> doneQueue_;
+
 	QToolBar *toolbar_;
 	ViewFinder *viewfinder_;
 	std::map<int, std::pair<void *, unsigned int>> mappedBuffers_;