The image captured by the framegrabber, the dimensions as well as all the drawing objects and shapes are displayed on the visualizer.
User can add element selecting features on the screen and edit them on the visualizer dragging the objects.
NOTE: While editing, you may see the visualizer has red border.
That's an indication that the image is currently frozen to allow the user to edit the program even if the framegrabber is keep acquiring new image.
Press Esc to exit the editing mode.