Improving the Consistency of Multi-LOD CityGML Datasets by Removing Redundancy

The CityGML standard enables the modelling of some topological relationships, and the representation in multiple levels of detail (LODs). However, both concepts are rarely utilised in reality. In this paper we investigate the linking of corresponding geometric features across multiple representations. We describe the possible topological cases, show how to detect these relationships, and how to store them explicitly. A software prototype has been implemented to detect matching features within and across LODs, and to automatically link them by establishing explicit topological relationships (with XLink). The experiments ran on our test datasets show a considerable number of matched geometries. Further, this method doubles as a lossless data compression method, considering that the storage footprint in the consolidated datasets has been reduced from their dissociated counterparts.