Create image callback using Qt signal

Former-commit-id: cf469ba01ffd26d286e6fb8d9f081cf126042e50

src/hyperion-v4l2/CMakeLists.txt

@@ -14,16 +14,21 @@ include_directories(
 	${QT_INCLUDES}
 )
 
-set(Hyperion_V4L2_HEADERS
-	ProtoConnection.h
+set(Hyperion_V4L2_QT_HEADERS
 	ImageHandler.h
+	ScreenshotHandler.h
+)
+
+set(Hyperion_V4L2_HEADERS
 	VideoStandardParameter.h
+	ProtoConnection.h
 )
 
 set(Hyperion_V4L2_SOURCES
 	hyperion-v4l2.cpp
 	ProtoConnection.cpp
 	ImageHandler.cpp
+	ScreenshotHandler.cpp
 )
 
 set(Hyperion_V4L2_PROTOS
@@ -34,9 +39,13 @@ protobuf_generate_cpp(Hyperion_V4L2_PROTO_SRCS Hyperion_V4L2_PROTO_HDRS
 	${Hyperion_V4L2_PROTOS}
 )
 
+QT4_WRAP_CPP(Hyperion_V4L2_MOC_SOURCES ${Hyperion_V4L2_QT_HEADERS})
+
 add_executable(hyperion-v4l2
 	${Hyperion_V4L2_HEADERS}
 	${Hyperion_V4L2_SOURCES}
+	${Hyperion_V4L2_QT_HEADERS}
+	${Hyperion_V4L2_MOC_SOURCES}
 	${Hyperion_V4L2_PROTO_SRCS}
 	${Hyperion_V4L2_PROTO_HDRS}
 )
@@ -48,5 +57,5 @@ target_link_libraries(hyperion-v4l2
 	hyperion-utils
 	${PROTOBUF_LIBRARIES}
 	pthread
-    ${QT_LIBRARIES}
+	${QT_LIBRARIES}
 )

src/hyperion-v4l2/ImageHandler.cpp

@@ -10,6 +10,10 @@ ImageHandler::ImageHandler(const std::string & address, int priority, double sig
 	_connection.setSkipReply(skipProtoReply);
 }
 
+ImageHandler::~ImageHandler()
+{
+}
+
 void ImageHandler::receiveImage(const Image<ColorRgb> & image)
 {
 	// check if we should do signal detection
@@ -32,10 +36,3 @@ void ImageHandler::receiveImage(const Image<ColorRgb> & image)
 		}
 	}
 }
-
-void ImageHandler::imageCallback(void *arg, const Image<ColorRgb> &image)
-{
-	ImageHandler * handler = static_cast<ImageHandler *>(arg);
-	handler->receiveImage(image);
-}
-

src/hyperion-v4l2/ImageHandler.h

@@ -1,24 +1,30 @@
+// Qt includes
+#include <QObject>
+
+// hyperion includes
+#include <utils/Image.h>
+#include <utils/ColorRgb.h>
+
 // blackborder includes
 #include <blackborder/BlackBorderProcessor.h>
 
-// hyperion-v4l includes
+// hyperion v4l2 includes
 #include "ProtoConnection.h"
 
 /// This class handles callbacks from the V4L2 grabber
-class ImageHandler
+class ImageHandler : public QObject
 {
+	Q_OBJECT
+
 public:
 	ImageHandler(const std::string & address, int priority, double signalThreshold, bool skipProtoReply);
+	virtual ~ImageHandler();
 
+public slots:
 	/// Handle a single image
 	/// @param image The image to process
 	void receiveImage(const Image<ColorRgb> & image);
 
-	/// static function used to direct callbacks to a ImageHandler object
-	/// @param arg This should be an ImageHandler instance
-	/// @param image The image to process
-	static void imageCallback(void * arg, const Image<ColorRgb> & image);
-
 private:
 	/// Priority for calls to Hyperion
 	const int _priority;

src/hyperion-v4l2/ScreenshotHandler.cpp

@@ -0,0 +1,25 @@
+// Qt includes
+#include <QImage>
+#include <QCoreApplication>
+
+// hyperion-v4l2 includes
+#include "ScreenshotHandler.h"
+
+ScreenshotHandler::ScreenshotHandler(const std::string & filename) :
+		_filename(filename)
+{
+}
+
+ScreenshotHandler::~ScreenshotHandler()
+{
+}
+
+void ScreenshotHandler::receiveImage(const Image<ColorRgb> & image)
+{
+	// store as PNG
+	QImage pngImage((const uint8_t *) image.memptr(), image.width(), image.height(), 3*image.width(), QImage::Format_RGB888);
+	pngImage.save(_filename.c_str());
+
+	// Quit the application after the first image
+	QCoreApplication::quit();
+}

src/hyperion-v4l2/ScreenshotHandler.h

@@ -0,0 +1,24 @@
+// Qt includes
+#include <QObject>
+
+// hyperionincludes
+#include <utils/Image.h>
+#include <utils/ColorRgb.h>
+
+/// This class handles callbacks from the V4L2 grabber
+class ScreenshotHandler : public QObject
+{
+	Q_OBJECT
+
+public:
+	ScreenshotHandler(const std::string & filename);
+	virtual ~ScreenshotHandler();
+
+public slots:
+	/// Handle a single image
+	/// @param image The image to process
+	void receiveImage(const Image<ColorRgb> & image);
+
+private:
+	const std::string _filename;
+};

src/hyperion-v4l2/hyperion-v4l2.cpp

@@ -4,7 +4,7 @@
 #include <clocale>
 
 // QT includes
-#include <QImage>
+#include <QCoreApplication>
 
 // getoptPlusPLus includes
 #include <getoptPlusPlus/getoptpp.h>
@@ -19,6 +19,7 @@
 #include "ProtoConnection.h"
 #include "VideoStandardParameter.h"
 #include "ImageHandler.h"
+#include "ScreenshotHandler.h"
 
 using namespace vlofgren;
 
@@ -32,8 +33,11 @@ void saveScreenshot(void *, const Image<ColorRgb> & image)
 
 int main(int argc, char** argv)
 {
+	QCoreApplication app(argc, argv);
+
 	// force the locale
 	setlocale(LC_ALL, "C");
+	QLocale::setDefault(QLocale::c());
 
 	try
 	{
@@ -113,31 +117,30 @@ int main(int argc, char** argv)
 		// set 3D mode if applicable
 		if (arg3DSBS.isSet())
 		{
-			grabber.set3D(V4L2Grabber::MODE_3DSBS);
+			grabber.set3D(VIDEO_3DSBS);
 		}
 		else if (arg3DTAB.isSet())
 		{
-			grabber.set3D(V4L2Grabber::MODE_3DTAB);
+			grabber.set3D(VIDEO_3DTAB);
 		}
 
-		// start the grabber
-		grabber.start();
-
 		// run the grabber
 		if (argScreenshot.isSet())
 		{
-			grabber.setCallback(&saveScreenshot, nullptr);
-			grabber.capture(1);
+			ScreenshotHandler handler("screenshot.png");
+			QObject::connect(&grabber, SIGNAL(newFrame(Image<ColorRgb>)), &handler, SLOT(receiveImage(Image<ColorRgb>)));
+			grabber.start();
+			QCoreApplication::exec();
+			grabber.stop();
 		}
 		else
 		{
 			ImageHandler handler(argAddress.getValue(), argPriority.getValue(), argSignalThreshold.getValue(), argSkipReply.isSet());
-			grabber.setCallback(&ImageHandler::imageCallback, &handler);
-			grabber.capture();
+			QObject::connect(&grabber, SIGNAL(newFrame(Image<ColorRgb>)), &handler, SLOT(receiveImage(Image<ColorRgb>)));
+			grabber.start();
+			QCoreApplication::exec();
+			grabber.stop();
 		}
-
-		// stop the grabber
-		grabber.stop();
 	}
 	catch (const std::runtime_error & e)
 	{