Question

need help on an application that draws basic shapes over video even when it plays. I am using AXWindowsMediaPlayer control for playing video and also put a custom Panel to draw shapes over player control. Custom panel is transparent.
can draw smoothly while video is not playing. But when it plays every thing goes wrong. the drawing over the video get erased. How i can overcome the issue ?
Please help.

Answer 1

i have found how to do this.
here is one way in WPF using Canvas

private void buttonPlayVideo_Click(object sender, RoutedEventArgs e)
{
    Microsoft.Win32.OpenFileDialog dlg = new Microsoft.Win32.OpenFileDialog();
    dlg.Filter = "All Files|*.*";
    Nullable<bool> result = dlg.ShowDialog();
    if (result == true) {
        MediaPlayer mp = new MediaPlayer();
        mp.Open(new Uri(filename));
        VideoDrawing vd = new VideoDrawing();
        vd.Player = mp;
        vd.Rect = new Rect(0, 0, 960, 540);
        DrawingBrush db = new DrawingBrush(vd);
        canvas.Background = db;
        mp.Play();
    }
}

then create mouse events for Canvas and draw with it

    Point startPoint, endPoint;
    private void canvas_MouseDown(object sender, MouseButtonEventArgs e)
    {
        startPoint = e.GetPosition(canvas);
    }
    private void canvas_MouseUp(object sender, MouseButtonEventArgs e)
    {
        endPoint = e.GetPosition(canvas);

        Line myLine = new Line();
        myLine.Stroke = System.Windows.Media.Brushes.LightSteelBlue;
        myLine.X1 = startPoint.X;
        myLine.Y1 = startPoint.Y;
        myLine.X2 = endPoint.X;
        myLine.Y2 = endPoint.Y;
        myLine.HorizontalAlignment = HorizontalAlignment.Left;
        myLine.VerticalAlignment = VerticalAlignment.Center;
        myLine.StrokeThickness = 2;
        canvas.Children.Add(myLine);
    }