Drawing to a custom view to display on cameraOverlayView

Hi

I am not sure what I am asking is possible or whether apple will allow it. I am trying to draw a rectangle onto a UIImagePickerController so that the user will be able to manipulate (resize) the rectangle using gestures. I understand the UIImagePickerController provide an cameraOverlayView function.

So here's my question. How do you draw a rectangle to a custom view and overlay that onto the UIImagePickerController using the cameraOverlayView function. Can this be done and if so, will apple allow me to then further allow the user to resize the rectangle through gestures?

Any help or direction will be appreciated.

Francois