Improvement of virtual line validation for cadastral map vectorization by direction and angle examination

In this study, an improvement for virtual line validation method which is developed in former study for vectorization of cadastral maps which contains null circles as nodes of parcel edges is proposed. The proposed method in this study makes virtual line validation between nodes which are edges of parcels more efficient and error proof by identifying direction and angle of lines connected to nodes. By identifying direction and angle of lines validation is made only between nodes which are in angle range of each other. In this manner processing speed is increased and faulty connections are decreased. Success rate for finding lines which connect nodes topologically is 79.16%.