Four directional adjacency graphs (FDAG) and their application in locating fields in forms
Jianxing Yuan, Yaqian Tang, C.Y. Suen · 2002
A new non-hierarchical spatial data structure named four directional adjacency graphs (FDAG) is proposed. In the FDAG vertical and horizontal neighborhood relationship between rectangles is well represented so that structural information can be easily extracted. An application for structural analysis of forms is given, where experiments are conducted with positive results.