protected virtual void OnVideoboxScrollEvent(object o, Gtk.ScrollEventArgs args)
{
switch (args.Event.Direction){
case ScrollDirection.Down:
SeekToPreviousFrame(InSegment());
break;
case ScrollDirection.Up:
SeekToNextFrame(InSegment());
break;
case ScrollDirection.Left:
StepBackward();
break;
case ScrollDirection.Right:
StepForward();
break;
}
}