Determining angles with a movable observer

We present a view planning approach to determining angles between two-line junctions on an object. Using view planning we demonstrate an ability to determine such angles without reconstruction of 3D properties, and without using known camera displacement. The core in our approach is a two-step view planning strategy based on two simple motion patterns. The view planning is controlled using local extrema in the apparent (viewed) angle. We demonstrate the approach on real images and experiments show an accuracy in determined angle which is better than ±1 degrees