Started implementation of Video Chat (not working yet!).

- GUI part is done
- implemented a very basic JPEG codec
- added echo frame in configuration panel
- created a video capture object that uses OpenCV (should be cross systems)
Remains to do:
- serialise and send frames through p3VoRS
- use a serious codec (e.g. Theora+x264)
- add icons to reflect camera state (failure/working/sending/...)
- compilation on windows 



git-svn-id: http://svn.code.sf.net/p/retroshare/code/trunk@7449 b45a01b8-16f6-495d-af2f-9b41ad6348cc

plugins/VOIP/gui/QVideoDevice.cpp

@@ -0,0 +1,102 @@
+#include <cv.h>
+#include <highgui.h>
+
+#include <QTimer>
+#include <QPainter>
+#include "QVideoDevice.h"
+#include "VideoProcessor.h"
+
+QVideoInputDevice::QVideoInputDevice(QWidget *parent)
+{
+	_timer = NULL ;
+	_capture_device = NULL ;
+	_video_encoder = NULL ;
+	_echo_output_device = NULL ;
+}
+
+void QVideoInputDevice::stop()
+{
+	if(_timer != NULL)
+	{
+		QObject::disconnect(_timer,SIGNAL(timeout()),this,SLOT(grabFrame())) ;
+		_timer->stop() ;
+		delete _timer ;
+		_timer = NULL ;
+	}
+	if(_capture_device != NULL)
+	{
+		cvReleaseCapture(&_capture_device) ;
+		_capture_device = NULL ;
+	}
+}
+void QVideoInputDevice::start()
+{
+	// make sure everything is re-initialised 
+	//
+	stop() ;
+
+	// Initialise la capture  
+	static const int cam_id = 0 ;
+	_capture_device = cvCaptureFromCAM(cam_id);
+
+	if(_capture_device == NULL)
+	{
+		std::cerr << "Cannot initialise camera. Something's wrong." << std::endl;
+		return ;
+	}
+
+	_timer = new QTimer ;
+	QObject::connect(_timer,SIGNAL(timeout()),this,SLOT(grabFrame())) ;
+
+	_timer->start(50) ;	// 10 images per second.
+}
+
+void QVideoInputDevice::grabFrame()
+{
+	IplImage *img=cvQueryFrame(_capture_device);    
+
+	if(img == NULL)
+	{
+		std::cerr << "(EE) Cannot capture image from camera. Something's wrong." << std::endl;
+		return ;
+	}
+	// get the image data
+
+	if(img->nChannels != 3)
+	{
+		std::cerr << "(EE) expected 3 channels. Got " << img->nChannels << std::endl;
+		cvReleaseImage(&img) ;
+		return ;
+	}
+
+	static const int _encoded_width = 128 ;
+	static const int _encoded_height = 128 ;
+
+	QImage image = QImage((uchar*)img->imageData,img->width,img->height,QImage::Format_RGB888).scaled(QSize(_encoded_width,_encoded_height),Qt::IgnoreAspectRatio,Qt::SmoothTransformation) ;
+
+	if(_video_encoder != NULL) _video_encoder->addImage(image) ;
+	if(_echo_output_device != NULL) _echo_output_device->showFrame(image) ;
+}
+
+QVideoInputDevice::~QVideoInputDevice()
+{
+	stop() ;
+}
+
+
+QVideoOutputDevice::QVideoOutputDevice(QWidget *parent)
+	: QLabel(parent)
+{
+	setPixmap(QPixmap(":/images/video-icon-big.png").scaled(170,128,Qt::KeepAspectRatio,Qt::SmoothTransformation)) ;
+}
+
+void QVideoOutputDevice::showFrame(const QImage& img)
+{
+	//std::cerr << "Displaying frame!!" << std::endl;
+
+	//QPainter painter(this) ;
+	//painter.drawImage(QPointF(0,0),img) ;
+
+	setPixmap(QPixmap::fromImage(img).scaled(minimumSize(),Qt::IgnoreAspectRatio,Qt::SmoothTransformation)) ;
+}
+