CalibrateWindow::CalibrateWindow(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::CalibrateWindow)
{
    ui->setupUi(this);

    ui->label_2->setText("HELLO world!!!");
    headHeight = 10;  //temporary set head height

    try{
        _capture = cvCaptureFromCAM(0);

        //IplImage* img = cvQueryFrame(_capture);

        cvSetCaptureProperty(_capture, CV_CAP_PROP_FPS, 10);
        _eye_cascade = (CvHaarClassifierCascade*)cvLoad("C:/haarcascade_eye_tree_eyeglasses.xml");
        _cascade = (CvHaarClassifierCascade*)cvLoad("C:/haarcascade_frontalface_alt2.xml");
        _storage = cvCreateMemStorage(0);
        _colors << cvScalar(0.0,0.0,255.0) << cvScalar(0.0,128.0,255.0)
                << cvScalar(0.0,255.0,255.0) << cvScalar(0.0,255.0,0.0)
                << cvScalar(255.0,128.0,0.0) << cvScalar(255.0,255.0,0.0)
                << cvScalar(255.0,0.0,0.0) << cvScalar(255.0,0.0,255.0);

        _timer = new QTimer(this);
        QObject::connect(_timer, SIGNAL(timeout()), this, SLOT(onCaptureTriggered()));
        _timer->start(10);
    }
    catch (std::exception& e){
        (new QErrorMessage(this))->showMessage("Something goes wrong with your application. Please, restart your application");
    }

}

void CalibrateWindow::onCaptureTriggered(){
    // Query camera for next frame
    _img = cvQueryFrame( _capture );
    if (_img)
    {
       // Detect objects
       cvClearMemStorage( _storage );
       CvSeq* objects = cvHaarDetectObjects( _img,
                                             _cascade,
                                             _storage,
                                             1.1,
                                             3,
                                             CV_HAAR_DO_CANNY_PRUNING,
                                             cvSize( 100, 100 ));
       int n = (objects ? objects->total : 0);
       CvRect* r;
       // Loop through objects and draw boxes
       for( int i = 0; i < n; i++ )
       {
          r = ( CvRect* )cvGetSeqElem( objects, i );
          cvRectangle( _img,
                       cvPoint( r->x, r->y ),
                       cvPoint( r->x + r->width, r->y + r->height ),
                       _colors[i%8]
                     );
          headHeight = r->height;
       }
       // Convert IplImage to QImage
       QImage image = QImage((const uchar *)_img->imageData,
                                            _img->width,
                                            _img->height,
                                            QImage::Format_RGB888).rgbSwapped();
       _pixmap = new QPixmap(QPixmap::fromImage(image));
       ui->captureLabel->setPixmap(*_pixmap);
}
}