Added functionality to disable the embedded v4l2 grabber when a higher priority source is active

Author: poljvd

deploy/hyperion.tar.gz

@@ -1,5 +1,8 @@
 #pragma once
 
+// Qt includes
+#include <QTimer>
+
 // Hyperion includes
 #include <hyperion/Hyperion.h>
 #include <hyperion/ImageProcessor.h>
@@ -44,6 +47,8 @@ public slots:
 private slots:
 	void newFrame(const Image<ColorRgb> & image);
 
+	void checkSources();
+
 private:
 	/// The timeout of the led colors [ms]
 	const int _timeout_ms;
@@ -62,4 +67,7 @@ private slots:
 
 	/// The list with computed led colors
 	std::vector<ColorRgb> _ledColors;
+
+	/// Timer which tests if a higher priority source is active
+	QTimer _timer;
 };

include/grabber/V4L2Wrapper.h

@@ -72,10 +72,7 @@ V4L2Grabber::V4L2Grabber(const std::string & device,
 V4L2Grabber::~V4L2Grabber()
 {
 	// stop if the grabber was not stopped
-	if (_streamNotifier != nullptr && _streamNotifier->isEnabled()) {
-		stop();
-	}
-
+	stop();
 	uninit_device();
 	close_device();
 }
@@ -103,14 +100,22 @@ void V4L2Grabber::setSignalThreshold(double redSignalThreshold, double greenSign
 
 void V4L2Grabber::start()
 {
-	_streamNotifier->setEnabled(true);
-	start_capturing();
+	if (_streamNotifier != nullptr && !_streamNotifier->isEnabled())
+	{
+		_streamNotifier->setEnabled(true);
+		start_capturing();
+		std::cout << "V4L2 grabber started" << std::endl;
+	}
 }
 
 void V4L2Grabber::stop()
 {
-	stop_capturing();
-	_streamNotifier->setEnabled(false);
+	if (_streamNotifier != nullptr && _streamNotifier->isEnabled())
+	{
+		stop_capturing();
+		_streamNotifier->setEnabled(false);
+		std::cout << "V4L2 grabber stopped" << std::endl;
+	}
 }
 
 void V4L2Grabber::open_device()
@@ -142,6 +147,7 @@ void V4L2Grabber::open_device()
 
 	// create the notifier for when a new frame is available
 	_streamNotifier = new QSocketNotifier(_fileDescriptor, QSocketNotifier::Read);
+	_streamNotifier->setEnabled(false);
 	connect(_streamNotifier, SIGNAL(activated(int)), this, SLOT(read_frame()));
 }
 

libsrc/grabber/v4l2/V4L2Grabber.cpp

@@ -28,7 +28,8 @@ V4L2Wrapper::V4L2Wrapper(const std::string &device,
 			pixelDecimation),
 	_processor(ImageProcessorFactory::getInstance().newImageProcessor()),
 	_hyperion(hyperion),
-	_ledColors(hyperion->getLedCount(), ColorRgb{0,0,0})
+	_ledColors(hyperion->getLedCount(), ColorRgb{0,0,0}),
+	_timer()
 {
 	// set the signal detection threshold of the grabber
 	_grabber.setSignalThreshold(
@@ -52,6 +53,13 @@ V4L2Wrapper::V4L2Wrapper(const std::string &device,
 				this, SIGNAL(emitColors(int,std::vector<ColorRgb>,int)),
 				_hyperion, SLOT(setColors(int,std::vector<ColorRgb>,int)),
 				Qt::QueuedConnection);
+
+	// setup the higher prio source checker
+	// this will disable the v4l2 grabber when a source with hisher priority is active
+	_timer.setInterval(500);
+	_timer.setSingleShot(false);
+	QObject::connect(&_timer, SIGNAL(timeout()), this, SLOT(checkSources()));
+	_timer.start();
 }
 
 V4L2Wrapper::~V4L2Wrapper()
@@ -88,3 +96,20 @@ void V4L2Wrapper::newFrame(const Image<ColorRgb> &image)
 	emit emitColors(_priority, _ledColors, _timeout_ms);
 }
 
+void V4L2Wrapper::checkSources()
+{
+	QList<int> activePriorities = _hyperion->getActivePriorities();
+
+	for (int x : activePriorities)
+	{
+		if (x < _priority)
+		{
+			// found a higher priority source: grabber should be disabled
+			_grabber.stop();
+			return;
+		}
+	}
+
+	// no higher priority source was found: grabber should be enabled
+	_grabber.start();
+}